Coronavirus vaccine | Patent Number 11241493

The present invention is directed to a nucleic acid suitable for use in treatment or prophylaxis of an infection with a coronavirus, preferably with a Coronavirus SARS-CoV-2, or a disorder related to such an infection, preferably COVID-19. The present invention is also directed to compositions, polypeptides, and vaccines. The compositions and vaccines preferably comprise at least one of said nucleic acid sequences, preferably nucleic acid sequences in association a lipid nanoparticle (LNP). The invention is also directed to first and second medical uses of the nucleic acid, the composition, the polypeptide, the combination, the vaccine, and the kit, and to methods of treating or preventing a coronavirus infection, preferably a Coronavirus infection.

The present application is a continuation of U.S. application Ser. No. 17/276,788, filed Mar. 16, 2021, which is a national phase application under 35 U.S.C. § 371 of International Application No. PCT/EP2021/052455, filed Feb. 3, 2021, which claims priority to U.S. Provisional Application No. 63/129,395, filed Dec. 22, 2020, U.S. Provisional Application No. 63/119,390, filed Nov. 30, 2020, U.S. Provisional Application No. 63/113,159, filed Nov. 12, 2020, U.S. Provisional Application No. 63/112,106, filed Nov. 10, 2020, International Application No. PCT/EP2020/080713, filed Nov. 2, 2020, International Application No. PCT/EP2020/079973, filed Oct. 23, 2020, International Application No. PCT/EP2020/079831, filed Oct. 22, 2020, International Application No. PCT/EP2020/065091, filed May 29, 2020, International Application No. PCT/EP2020/059687, filed Apr. 3, 2020, and International Application No. PCT/EP2020/052775, filed Feb. 4, 2020, the entire contents of each of which are hereby incorporated by reference.

The sequence listing that is contained in the file named “CRVCP0311USC1_ST25.txt”, which is 159 MB (as measured in Microsoft Windows®) and was created on Apr. 11, 2021, is filed concurrently herewith on compact discs by Priority Express Mail and is incorporated by reference herein.

The present invention is inter alia directed to a nucleic acid suitable for use in treatment or prophylaxis of an infection with a coronavirus, preferably with a coronavirus SARS-CoV-2, or a disorder related to such an infection, preferably COVID-19. The present invention is also directed to compositions, polypeptides, and vaccines. The compositions and vaccines preferably comprise at least one of said nucleic acid sequences, preferably nucleic acid sequences in association with a polymeric carrier, a polycationic protein or peptide, or a lipid nanoparticle (LNP). The invention is also directed to first and second medical uses of the nucleic acid, the composition, the polypeptide, the vaccine, and the kit, and to methods of treating or preventing a coronavirus infection, preferably a SARS-CoV-2 infection.

Coronaviruses are enveloped, positive single stranded RNA viruses of the Coronaviridae family.

Their representatives cause very various diseases in different vertebrates such as mammals, birds and fish.

Coronaviruses are genetically highly variable, and individual virus species can also infect several host species by overcoming the species barrier. Such transfers have resulted in infections in humans with the SARS-associated coronavirus (SARS-CoV) and with the Middle East respiratory syndrome coronavirus (MERS-CoV). The coronavirus epidemic that started in the Chinese city of Wuhan at the turn of 2019/2020 is attributed to a previously unknown coronavirus, which was given the preliminary names nCoV-2019 or Wuhan Human Coronavirus (WHCV); later the virus was given the official name SARS-CoV-2.

Typical symptoms of a SARS-CoV-2 caused virus infection, also referred to as COVID-19 disease (Coronavirus disease 2019), include fever, cough, shortness of breath, pneumonia and gastrointestinal symptoms (e.g. diarrhoea). Severe illness can lead to respiratory failure that requires mechanical ventilation and support in an intensive care unit. On 30 Jan. 2020, the world health organization (WHO) declared a global health emergency over that novel coronavirus outbreak. On March 11, the WHO declared COVID-19 a pandemic, pointing to the over 118,000 cases of the coronavirus illness in over 110 countries and territories around the world and the sustained risk of further global spread. By end of March 2020, there were more than 800,000 confirmed cases of a SARS-CoV-2 infection, spreading across almost every country in the world, with more than 40,000 COVID-19 associated deaths.

At present, no vaccine or specific treatment is available for a SARS-CoV-2 infection and/or COVID-19 disease.

Patients diagnosed with a SARS-CoV-2 infection merely receive supportive treatment based on the individual's symptoms and clinical condition. Due to the substantial risk of a severe global pandemic, there is an urgent need for a safe and effective treatment or prophylaxis of SARS-CoV-2 infections. In particular, a vaccine is needed to protect the elderly population where high mortality rates have been observed.

Nucleic acid based vaccination, including DNA or RNA, represents a promising technique for novel vaccines against emerging viruses. Nucleic acids can be genetically engineered and administered to a human subject. Transfected cells directly produce the encoded antigen (e.g. provided by a DNA or an RNA, in particular an mRNA), which results in protective immunological responses.

A pivotal role for virus-specific memory T-cells in broad and long-term protection against SARS-CoV infection has been elucidated (see e.g. Channappanavar, Rudragouda, et al. “Virus-specific memory CD8 T cells provide substantial protection from lethal severe acute respiratory syndrome coronavirus infection.” Journal of virology 88.19 (2014): 11034-11044). Virus-specific CD8 T cells are e.g. required for pathogen clearance and for mediating protection after viral challenge. An effective SARS-CoV-2 vaccine should therefore not only induce strong functional humoral immune responses, but also induce SARS-CoV-2 specific CD8+ T-cell and CD4+ T-cell responses.

Therefore, it is the object of the underlying invention to provide a nucleic acid based vaccine for coronavirus infections, in particular for SARS-CoV-2 infections. It is a further object of the present invention to provide an effective coronavirus vaccine, which can be stored and transported without cold chain and which enables rapid and scalable coronavirus vaccine production.

As further defined in the claims and the underlying description, these objects are inter alia solved by providing a nucleic acid, e.g. an RNA or a DNA, comprising at least one coding sequence encoding at least one antigenic peptide or protein derived from a coronavirus SARS-CoV-2.

Further, it would be desirable that such a nucleic acid, or e.g. a composition/vaccine comprising said nucleic acid has at least some of the following advantageous features:

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  • Translation of the nucleic acid at the site of injection/vaccination (e.g. muscle);
  
  
  • Very efficient induction of antigen-specific immune responses against the encoded SARS-CoV-2 protein at a very low dosage and dosing regimen;
  
  
  • Suitability for vaccination of infants and/or newborns or the elderly, in particular the elderly;
  
  
  • Suitability of the composition/vaccine for intramuscular administration;
  
  
  • Induction of specific and functional humoral immune response against coronavirus, in e.g. SARS-CoV-2;
  
  
  • Induction of broad, functional cellular T-cell responses against coronavirus, in e.g. SARS-CoV-2;
  
  
  • Induction of specific B-cell memory against coronavirus, in e.g. SARS-CoV-2;
  
  
  • Induction of functional antibodies that can effectively neutralize the virus, e.g. SARS-CoV-2;
  
  
  • Induction of functional antibodies that can effectively neutralize emerging variants of SARS-CoV-2;
  
  
  • Eliciting of mucosal IgA immunity by inducing of mucosal IgA antibodies,
  
  
  • Induction of a well-balanced B cell and T cell responses;
  
  
  • Induction of protective immunity against coronavirus infection, e.g. against SARS-CoV-2 or emerging variants thereof;
  
  
  • Fast onset of immune protection against coronavirus, in e.g. SARS-CoV-2;
  
  
  • Longevity of the induced immune responses against coronavirus, in e.g. SARS-CoV-2;
  
  
  • No enhancement of a SARS-CoV-2 infection due to vaccination or immunopathological effects;
  
  
  • No antibody dependent enhancement (ADE) caused by the nucleic acid based SARS-CoV-2 vaccine;
  
  
  • No excessive induction of systemic cytokine or chemokine response after application of the vaccine, which could lead to an undesired high reactogenicity upon vaccination;
  
  
  • Well tolerability, no side-effects, non-toxicity of the vaccine;
  
  
  • Advantageous stability characteristics of the nucleic acid-based vaccine;
  
  
  • Speed, adaptability, simplicity and scalability of coronavirus vaccine production;
  
  
  • Advantageous vaccination regimen that only requires one or two vaccination for sufficient protection.
  
  
  • Advantageous vaccination regimen that only requires a low dose of the composition/vaccine for sufficient protection.
  
  
  
  

For the sake of clarity and readability, the following definitions are provided. Any technical feature mentioned for these definitions may be read on each and every embodiment of the invention. Additional definitions and explanations may be specifically provided in the context of these embodiments.

Percentages in the context of numbers should be understood as relative to the total number of the respective items. In other cases, and unless the context dictates otherwise, percentages should be understood as percentages by weight (wt.-%).

About: The term “about” is used when determinants or values do not need to be identical, i.e. 100% the same. Accordingly, “about” means, that a determinant or values may diverge by 0.1% to 20%, preferably by 0.1% to 10%; in particular, by 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%. The skilled person will know that e.g. certain parameters or determinants may slightly vary based on the method how the parameter was determined. For example, if a certain determinants or value is defined herein to have e.g. a length of “about 1000 nucleotides”, the length may diverge by 0.1% to 20%, preferably by 0.1% to 10%; in particular, by 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%. Accordingly, the skilled person will know that in that specific example, the length may diverge by 1 to 200 nucleotides, preferably by 1 to 200 nucleotides; in particular, by 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200 nucleotides.

Adaptive immune response: The term “adaptive immune response” as used herein will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to an antigen-specific response of the immune system (the adaptive immune system). Antigen specificity allows for the generation of responses that are tailored to specific pathogens or pathogen-infected cells. The ability to mount these tailored responses is usually maintained in the body by “memory cells” (B-cells). In the context of the invention, the antigen is provided by the nucleic acid (e.g. an RNA or a DNA) encoding at least one antigenic peptide or protein derived from coronavirus, preferably from SARS-CoV-2 (nCoV-2019).

Antigen: The term “antigen” as used herein will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a substance which may be recognized by the immune system, preferably by the adaptive immune system, and is capable of triggering an antigen-specific immune response, e.g. by formation of antibodies and/or antigen-specific T cells as part of an adaptive immune response. Typically, an antigen may be or may comprise a peptide or protein, which may be presented by the MHC to T-cells. Also fragments, variants and derivatives of peptides or proteins derived from e.g. spike protein (S) of coronavirus, preferably from SARS-CoV-2 (nCoV-2019) comprising at least one epitope are understood as antigens in the context of the invention. In the context of the present invention, an antigen may be the product of translation of a provided nucleic acid as specified herein.

Antigenic peptide or protein: The term “antigenic peptide or protein” or “immunogenic peptide or protein” will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a peptide, protein derived from a (antigenic or immunogenic) protein which stimulates the body's adaptive immune system to provide an adaptive immune response. Therefore an antigenic/immunogenic peptide or protein comprises at least one epitope (as defined herein) or antigen (as defined herein) of the protein it is derived from (e.g., spike protein (S) of coronavirus, preferably from SARS-CoV-2 (nCoV-2019)).

Cationic: Unless a different meaning is clear from the specific context, the term “cationic” means that the respective structure bears a positive charge, either permanently or not permanently, but in response to certain conditions such as pH. Thus, the term “cationic” covers both “permanently cationic” and “cationisable”.

Cationisable: The term “cationisable” as used herein means that a compound, or group or atom, is positively charged at a lower pH and uncharged at a higher pH of its environment. Also in non-aqueous environments where no pH value can be determined, a cationisable compound, group or atom is positively charged at a high hydrogen ion concentration and uncharged at a low concentration or activity of hydrogen ions. It depends on the individual properties of the cationisable or polycationisable compound, in particular the pKa of the respective cationisable group or atom, at which pH or hydrogen ion concentration it is charged or uncharged. In diluted aqueous environments, the fraction of cationisable compounds, groups or atoms bearing a positive charge may be estimated using the so-called Henderson-Hasselbalch equation, which is well-known to a person skilled in the art. E.g., in some embodiments, if a compound or moiety is cationisable, it is preferred that it is positively charged at a pH value of about 1 to 9, preferably 4 to 9, 5 to 8 or even 6 to 8, more preferably of a pH value of or below 9, of or below 8, of or below 7, most preferably at physiological pH values, e.g. about 7.3 to 7.4, i.e. under physiological conditions, particularly under physiological salt conditions of the cell in vivo. In other embodiments, it is preferred that the cationisable compound or moiety is predominantly neutral at physiological pH values, e.g. about 7.0-7.4, but becomes positively charged at lower pH values. In some embodiments, the preferred range of pKa for the cationisable compound or moiety is about 5 to about 7.

Coding sequence/coding region: The terms “coding sequence” or “coding region” and the corresponding abbreviation “cds” as used herein will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a sequence of several nucleotide triplets, which may be translated into a peptide or protein. A coding sequence in the context of the present invention may be a DNA sequence, preferably an RNA sequence, consisting of a number of nucleotides that may be divided by three, which starts with a start codon and which preferably terminates with a stop codon.

Derived from: The term “derived from” as used throughout the present specification in the context of a nucleic acid, i.e. for a nucleic acid “derived from” (another) nucleic acid, means that the nucleic acid, which is derived from (another) nucleic acid, shares e.g. at least 60%, 70%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the nucleic acid from which it is derived. The skilled person is aware that sequence identity is typically calculated for the same types of nucleic acids, i.e. for DNA sequences or for RNA sequences. Thus, it is understood, if a DNA is “derived from” an RNA or if an RNA is “derived from” a DNA, in a first step the RNA sequence is converted into the corresponding DNA sequence (in particular by replacing the uracils (U) by thymidines (T) throughout the sequence) or, vice versa, the DNA sequence is converted into the corresponding RNA sequence (in particular by replacing the T by U throughout the sequence). Thereafter, the sequence identity of the DNA sequences or the sequence identity of the RNA sequences is determined. Preferably, a nucleic acid “derived from” a nucleic acid also refers to nucleic acid, which is modified in comparison to the nucleic acid from which it is derived, e.g. in order to increase RNA stability even further and/or to prolong and/or increase protein production. In the context of amino acid sequences (e.g. antigenic peptides or proteins) the term “derived from” means that the amino acid sequence, which is derived from (another) amino acid sequence, shares e.g. at least 60%, 70%, 75%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence from which it is derived.

Epitope: The term “epitope” (also called “antigen determinant” in the art) as used herein will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to T cell epitopes and B cell epitopes. T cell epitopes or parts of the antigenic peptides or proteins and may comprise fragments preferably having a length of about 6 to about 20 or even more amino acids, e.g. fragments as processed and presented by MHC class I molecules, preferably having a length of about 8 to about 10 amino acids, e.g. 8, 9, or 10, (or even 11, or 12 amino acids), or fragments as processed and presented by MHC class II molecules, preferably having a length of about 13 to about 20 or even more amino acids. These fragments are typically recognized by T cells in form of a complex consisting of the peptide fragment and an MHC molecule, i.e. the fragments are typically not recognized in their native form. B cell epitopes are typically fragments located on the outer surface of (native) protein or peptide antigens, preferably having 5 to 15 amino acids, more preferably having 5 to 12 amino acids, even more preferably having 6 to 9 amino acids, which may be recognized by antibodies, i.e. in their native form. Such epitopes of proteins or peptides may furthermore be selected from any of the herein mentioned variants of such proteins or peptides. In this context epitopes can be conformational or discontinuous epitopes which are composed of segments of the proteins or peptides as defined herein that are discontinuous in the amino acid sequence of the proteins or peptides as defined herein but are brought together in the three-dimensional structure or continuous or linear epitopes which are composed of a single polypeptide chain.

Fragment: The term “fragment” as used throughout the present specification in the context of a nucleic acid sequence (e.g. RNA or a DNA) or an amino acid sequence may typically be a shorter portion of a full-length sequence of e.g. a nucleic acid sequence or an amino acid sequence. Accordingly, a fragment, typically, consists of a sequence that is identical to the corresponding stretch within the full-length sequence. A preferred fragment of a sequence in the context of the present invention, consists of a continuous stretch of entities, such as nucleotides or amino acids corresponding to a continuous stretch of entities in the molecule the fragment is derived from, which represents at least 40%, 50%, 60%, 70%, 80%, 90%, 95% of the total (i.e. full-length) molecule from which the fragment is derived (e.g. spike protein (S) of coronavirus, preferably from SARS-CoV-2 (nCoV-2019)). The term “fragment” as used throughout the present specification in the context of proteins or peptides may, typically, comprise a sequence of a protein or peptide as defined herein, which is, with regard to its amino acid sequence, N-terminally and/or C-terminally truncated compared to the amino acid sequence of the original protein. Such truncation may thus occur either on the amino acid level or correspondingly on the nucleic acid level. A sequence identity with respect to such a fragment as defined herein may therefore preferably refer to the entire protein or peptide as defined herein or to the entire (coding) nucleic acid molecule of such a protein or peptide. Fragments of proteins or peptides may comprise at least one epitope of those proteins or peptides.

Heterologous: The terms “heterologous” or “heterologous sequence” as used throughout the present specification in the context of a nucleic acid sequence or an amino acid sequence refers to a sequence (e.g. RNA, DNA, amino acid) has to be understood as a sequence that is derived from another gene, another allele, or e.g. another species or virus. Two sequences are typically understood to be “heterologous” if they are not derivable from the same gene or from the same allele. I.e., although heterologous sequences may be derivable from the same organism or virus, in nature, they do not occur in the same nucleic acid or protein.

Humoral immune response: The terms “humoral immunity” or “humoral immune response” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to B-cell mediated antibody production and optionally to accessory processes accompanying antibody production. A humoral immune response may be typically characterized, e.g. by Th2 activation and cytokine production, germinal center formation and isotype switching, affinity maturation and memory cell generation. Humoral immunity may also refer to the effector functions of antibodies, which include pathogen and toxin neutralization, classical complement activation, and opsonin promotion of phagocytosis and pathogen elimination.

Identity (of a sequence): The term “identity” as used throughout the present specification in the context of a nucleic acid sequence or an amino acid sequence will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to the percentage to which two sequences are identical. To determine the percentage to which two sequences are identical, e.g. nucleic acid sequences or amino acid (aa) sequences as defined herein, preferably the aa sequences encoded by the nucleic acid sequence as defined herein or the aa sequences themselves, the sequences can be aligned in order to be subsequently compared to one another. Therefore, e.g. a position of a first sequence may be compared with the corresponding position of the second sequence. If a position in the first sequence is occupied by the same residue as is the case at a position in the second sequence, the two sequences are identical at this position. If this is not the case, the sequences differ at this position. If insertions occur in the second sequence in comparison to the first sequence, gaps can be inserted into the first sequence to allow a further alignment. If deletions occur in the second sequence in comparison to the first sequence, gaps can be inserted into the second sequence to allow a further alignment. The percentage to which two sequences are identical is then a function of the number of identical positions divided by the total number of positions including those positions which are only occupied in one sequence. The percentage to which two sequences are identical can be determined using an algorithm, e.g. an algorithm integrated in the BLAST program.

Immunogen, immunogenic: The terms “immunogen” or “immunogenic” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a compound that is able to stimulate/induce an immune response. Preferably, an immunogen is a peptide, polypeptide, or protein. An immunogen in the sense of the present invention is the product of translation of a provided nucleic acid, comprising at least one coding sequence encoding at least one antigenic peptide, protein derived from spike protein (S) of SARS-CoV-2 (nCoV-2019) as defined herein. Typically, an immunogen elicits an adaptive immune response.

Immune response: The term “immune response” will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a specific reaction of the adaptive immune system to a particular antigen (so called specific or adaptive immune response) or an unspecific reaction of the innate immune system (so called unspecific or innate immune response), or a combination thereof.

Immune system: The term “immune system” will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a system of the organism that may protect the organisms from infection. If a pathogen succeeds in passing a physical barrier of an organism and enters this organism, the innate immune system provides an immediate, but non-specific response. If pathogens evade this innate response, vertebrates possess a second layer of protection, the adaptive immune system. Here, the immune system adapts its response during an infection to improve its recognition of the pathogen. This improved response is then retained after the pathogen has been eliminated, in the form of an immunological memory, and allows the adaptive immune system to mount faster and stronger attacks each time this pathogen is encountered. According to this, the immune system comprises the innate and the adaptive immune system. Each of these two parts typically contains so called humoral and cellular components.

Innate immune system: The term “innate immune system” (also known as non-specific or unspecific immune system) will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a system typically comprising the cells and mechanisms that defend the host from infection by other organisms in a non-specific manner. This means that the cells of the innate system may recognize and respond to pathogens in a generic way, but unlike the adaptive immune system, it does not confer long-lasting or protective immunity to the host. The innate immune system may be activated by ligands of pattern recognition receptor e.g. Toll-like receptors, NOD-like receptors, or RIG-I like receptors etc.

Lipidoid compound: A lipidoid compound, also simply referred to as lipidoid, is a lipid-like compound, i.e. an amphiphilic compound with lipid-like physical properties. In the context of the present invention, the term lipid is considered to encompass lipidoid compounds.

Permanently cationic: The term “permanently cationic” as used herein will be recognized and understood by the person of ordinary skill in the art, and means, e.g., that the respective compound, or group, or atom, is positively charged at any pH value or hydrogen ion activity of its environment. Typically, the positive charge results from the presence of a quaternary nitrogen atom. Where a compound carries a plurality of such positive charges, it may be referred to as permanently polycationic.

Stabilized RNA: The term “stabilized RNA” refer to an RNA that is modified such, that it is more stable to disintegration or degradation, e.g., by environmental factors or enzymatic digest, such as by exo- or endonuclease degradation, compared to an RNA without such modification. Preferably, a stabilized RNA in the context of the present invention is stabilized in a cell, such as a prokaryotic or eukaryotic cell, preferably in a mammalian cell, such as a human cell. The stabilization effect may also be exerted outside of cells, e.g. in a buffer solution etc., e.g., for storage of a composition comprising the stabilized RNA.

T-cell responses: The terms “cellular immunity” or “cellular immune response” or “cellular T-cell responses” as used herein will be recognized and understood by the person of ordinary skill in the art, and are for example intended to refer to the activation of macrophages, natural killer cells (NK), antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen. In more general terms, cellular immunity is not based on antibodies, but on the activation of cells of the immune system. Typically, a cellular immune response may be characterized e.g. by activating antigen-specific cytotoxic T-lymphocytes that are able to induce apoptosis in cells, e.g. specific immune cells like dendritic cells or other cells, displaying epitopes of foreign antigens on their surface.

Variant (of a sequence): The term “variant” as used throughout the present specification in the context of a nucleic acid sequence will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a variant of a nucleic acid sequence derived from another nucleic acid sequence. E.g., a variant of a nucleic acid sequence may exhibit one or more nucleotide deletions, insertions, additions and/or substitutions compared to the nucleic acid sequence from which the variant is derived. A variant of a nucleic acid sequence may at least 50%, 60%, 70%, 80%, 90%, or 95% identical to the nucleic acid sequence the variant is derived from. The variant is a functional variant in the sense that the variant has retained at least 50%, 60%, 70%, 80%, 90%, or 95% or more of the function of the sequence where it is derived from. A “variant” of a nucleic acid sequence may have at least 70%, 75%, 80%, 85%, 90%, 95%, 98% or 99% nucleotide identity over a stretch of at least 10, 20, 30, 50, 75 or 100 nucleotide of such nucleic acid sequence.

The term “variant” as used throughout the present specification in the context of proteins or peptides is e.g. intended to refer to a proteins or peptide variant having an amino acid sequence which differs from the original sequence in one or more mutation(s)/substitution(s), such as one or more substituted, inserted and/or deleted amino acid(s). Preferably, these fragments and/or variants have the same, or a comparable specific antigenic property (immunogenic variants, antigenic variants). Insertions and substitutions are possible, in particular, at those sequence positions which cause no modification to the three-dimensional structure or do not affect the binding region. Modifications to a three-dimensional structure by insertion(s) or deletion(s) can easily be determined e.g. using CD spectra (circular dichroism spectra). A “variant” of a protein or peptide may have at least 70%, 75%, 80%, 85%, 90%, 95%, 98% or 99% amino acid identity over a stretch of at least 10, 20, 30, 50, 75 or 100 amino acids of such protein or peptide. Preferably, a variant of a protein comprises a functional variant of the protein, which means, in the context of the invention, that the variant exerts essentially the same, or at least 40%, 50%, 60%, 70%, 80%, 90% of the immunogenicity as the protein it is derived from.

The present invention is based on the inventor's surprising finding that at least one peptide or protein derived from coronavirus SARS-CoV-2 (formerly called nCoV-2019), provided by the coding sequence of a nucleic acid, e.g. an RNA, can efficiently be expressed in human cells (Examples 2a, 2b, and 2c). Even more surprising and unexpected, the administration of a composition comprising said nucleic acid, e.g. said RNA, induces antigen-specific immune responses against coronavirus, in particular against coronavirus SARS-CoV-2 (see Example section).

Even more unexpected, the inventors showed that the coding RNA of the invention induces high levels of functional antibodies, shown by high virus neutralizing titers (VNTs) and T-cell responses (vaccines induce double positive CD4+ and CD8+ T-cells (see e.g. Example 7 and Example 10), and even protects hamsters and NHPs from SARS-CoV-2 challenge infection (see Example 9 and Example 15), indicating that the coding RNA or the composition/vaccine of the invention is therefore suitable for use as a vaccine, e.g. as a vaccine in human subjects.

Those findings are the basis for the provision of a nucleic acid based coronavirus vaccine.

In a first aspect, the present invention provides a nucleic acid for a coronavirus vaccine, preferably a coronavirus SARS-CoV-2 vaccine, wherein said nucleic acid comprises at least one coding sequence encoding at least one antigenic peptide or protein of an SARS-CoV-2 coronavirus, or an immunogenic fragment or immunogenic variant thereof.

In a second aspect, the present invention provides a composition, preferably an immunogenic composition comprising at least one nucleic acid of the first aspect. Suitably, the composition may comprise at least one nucleic acid, e.g. at least one coding RNA, complexed with, encapsulated in, or associated with one or more lipids, thereby forming lipid nanoparticles.

In a third aspect, the present invention provides antigenic polypeptides for a coronavirus vaccine, preferably for an SARS-CoV-2 composition or vaccine.

In a fourth aspect, the present invention provides a coronavirus vaccine, preferably an SARS-CoV-2 vaccine, wherein the vaccine comprises at least one nucleic acid of the first aspect, or the composition of the second aspect, or at least one polypeptide of the third aspect.

In a fifth aspect, the present invention provides a kit or kit of parts comprising at least one nucleic acid of the first aspect, and/or at least one composition of the second aspect, and/or at least one polypeptide of the third aspect, and/or at least one vaccine of the forth aspect.

In a sixth aspect, the present invention provides a combination comprising at least two separate components, wherein the at least at least two separate components are selected from two nucleic acids of the first aspect, and/or at least two compositions of the second aspect, and/or at least two polypeptides of the third aspect, and/or at least two vaccine of the forth aspect.

Further aspects of the invention concern a method of treating or preventing coronavirus infection, preferably an SARS-CoV-2 infection in a subject, and first and second medical uses of nucleic acid, compositions, and vaccines. Also provided are methods of manufacturing the nucleic acid, the composition, or the vaccine.

The present application is filed together with a sequence listing in electronic format, which is part of the description of the present application (WIPO standard ST.25). The information contained in the sequence listing is incorporated herein by reference in its entirety. Where reference is made herein to a “SEQ ID NO”, the corresponding nucleic acid sequence or amino acid (aa) sequence in the sequence listing having the respective identifier is referred to. For many sequences, the sequence listing also provides additional detailed information, e.g. regarding certain structural features, sequence optimizations, GenBank (NCBI) or GISAID (epi) identifiers, or additional detailed information regarding its coding capacity. In particular, such information is provided under numeric identifier <223> in the WIPO standard ST.25 sequence listing. Accordingly, information provided under said numeric identifier <223> is explicitly included herein in its entirety and has to be understood as integral part of the description of the underlying invention.

Nucleic Acid for a Coronavirus Vaccine:

In a first aspect, the invention relates to a nucleic acid suitable for a coronavirus vaccine.

It has to be noted that specific features and embodiments that are described in the context of the first aspect of the invention, that is the nucleic acid of the invention, are likewise applicable to the second aspect (composition of the invention), the third aspect (polypeptide of the invention), the forth aspect (vaccine of the invention), the fifth aspect (kit or kit of parts of the invention), or further aspects including medical uses and method of treatments.

Coronaviruses can be classified into the genus Alphacoronavirus, Betacoronavirus, Deltacoronavirus, Gammacoronavirus, and unclassified Coronaviruses. Coronaviruses are genetically highly variable, and individual virus species can also infect several host species by overcoming the species barrier. Human coronaviruses include SARS-associated coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and coronavirus SARS-CoV-2 (previously named “Wuhan Human coronavirus” or nCoV-2019). Accordingly, the nucleic acid may be suitable for a vaccine against a coronavirus, preferably against a coronavirus that is a human pathogen, most preferably against the novel emerging coronavirus SARS-CoV-2 (nCoV-2019).

The terms “nucleic acid” or “nucleic acid molecule” will be recognized and understood by the person of ordinary skill in the art. The term “nucleic acid” or “nucleic acid molecule” as used herein preferably refers to DNA (molecules) or RNA (molecules). It is preferably used synonymously with the term polynucleotide. Preferably, a nucleic acid or a nucleic acid molecule is a polymer comprising or consisting of nucleotide monomers, which are covalently linked to each other by phosphodiester-bonds of a sugar/phosphate-backbone. The term “nucleic acid molecule” also encompasses modified nucleic acid molecules, such as base-modified, sugar-modified or backbone-modified DNA or RNA molecules as defined herein.

The nucleic acid of the first aspect, e.g. the DNA or the RNA, may form the basis for a nucleic acid based composition or vaccine. Generally, protein-based vaccines, or live attenuated vaccines, are suboptimal for use in developing countries due to their high production costs. In addition, protein-based vaccines, or live attenuated vaccines require long development times and are not suitable for rapid responses of pandemic virus outbreaks such as the Coronavirus SARS-CoV-2 outbreak in 2019/2020. In contrast, the nucleic acid-based vaccines according to the present invention allow very fast and cost-effective production. Therefore, in comparison with known vaccines, vaccine based on the inventive nucleic acid can be produced significantly cheaper and faster, which is very advantageous particularly for use in developing countries. One further advantage of a vaccine based on the inventive nucleic acid may be its temperature-stability in comparison to protein or peptide-based vaccines. However, a vaccine based on a polypeptide is also in the scope of the underlying invention (see e.g. third aspect).

The terms “nucleic acid sequence”, “DNA sequence”, “RNA sequence” will be recognized and understood by the person of ordinary skill in the art, and e.g. refer to a particular and individual order of the succession of its nucleotides.

In a preferred embodiment of the first aspect, the nucleic acid comprises at least one coding sequence encoding at least one antigenic peptide or protein from a SARS-CoV-2 (nCoV-2019) coronavirus, or an immunogenic fragment or immunogenic variant thereof.

The term “antigenic peptide or protein from a SARS-CoV-2 coronavirus” has to be understood as (i) an antigen that is from a SARS-CoV-2 coronavirus which means that the amino acid sequence of the antigenic peptide or protein (or a fragment thereof) is identical to a SARS-CoV-2 coronavirus protein (or a fragment thereof), or (ii) an antigen that is derived from a SARS-CoV-2 coronavirus which means that the amino acid sequence of the antigenic peptide or protein (or a fragment thereof) is not identical to a corresponding SARS-CoV-2 coronavirus protein (or a fragment thereof).

Accordingly, in a preferred embodiment of the first aspect, the nucleic acid comprises at least one coding sequence encoding at least one antigenic peptide or protein that is or is derived from an SARS-CoV-2 (nCoV-2019) coronavirus, or an immunogenic fragment or immunogenic variant thereof.

The term “antigenic peptide or protein that is or is derived from a SARS-CoV-2 (nCoV-2019) coronavirus” has to be understood as (i) an antigen that “is from a SARS-CoV-2 coronavirus” which means that the amino acid sequence of the antigenic peptide or protein (or a fragment thereof) is identical in sequence to a SARS-CoV-2 coronavirus protein (or a fragment thereof), or (ii) an antigen that “is derived from a SARS-CoV-2 coronavirus” which means that the amino acid sequence of the antigenic peptide or protein (or a fragment thereof) is not identical to a sequence of a corresponding SARS-CoV-2 coronavirus protein (or a fragment thereof).

In preferred embodiments, the nucleic acid comprises at least one coding sequence encoding at least one antigenic peptide or protein that is or is derived from an SARS-CoV-2 (nCoV-2019) coronavirus, or an immunogenic fragment or immunogenic variant thereof, wherein the nucleic acid comprises at least one heterologous untranslated region (UTR).

The term “untranslated region” or “UTR” or “UTR element” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a part of a nucleic acid molecule typically located 5′ or 3′ located of a coding sequence. An UTR is not translated into protein. An UTR may be part of a nucleic acid, e.g. a DNA or an RNA. An UTR may comprise elements for controlling gene expression, also called regulatory elements. Such regulatory elements may be, e.g., ribosomal binding sites, miRNA binding sites etc.

As used herein, the terms “Human coronavirus 2019”, “Wuhan Human coronavirus” (WHCV), “nCoV-2019 coronavirus”, “nCoV-2019”, “Wuhan seafood market pneumonia virus”, “Wuhan coronavirus”, “WHCV coronavirus”, “HCoV-19”, “SARS2”, “COVID-19 virus”, “hCoV-19”, “SARS-CoV-2”, or “coronavirus SARS-CoV-2” may be used interchangeable throughout the present invention, relating to a new pandemic coronavirus that has been emerged in the Chinese city of Wuhan at the turn of 2019/2020, causing the disease COVID-19. According to the WHO (February 2020), the virus is officially termed “SARS-CoV-2”, and the associated disease is officially termed “COVID-19”.

The virus SARS-CoV-2 belongs to the Coronaviridae, in particular to Orthocoronaviruses, more specifically to the genus Betacoronavirus. Exemplary SARS-CoV-2 coronaviruses are isolates including but not limited to those provided in List A and B below.

List A: Exemplary SARS-CoV-2 Coronavirus Isolates (EPI/GISAID):

EPI_ISL_402119, EPI_ISL_402120, EPI_ISL_402121, EPI_ISL_402123, EPI_ISL_402124 (hCoV-19/Wuhan/WIV04/2019), EPI_ISL_402125, EPI_ISL_402127, EPI EPI_ISL_402128 (hCoV-19/Wuhan/WIV05/2019; WIV05; SARS-CoV-2/Wuhan/WIV05/2019_EPI_ISL_402128), EPI_ISL_402129, EPI_ISL_402130, EPI_ISL_402131, EPI_ISL_402132, EPI_ISL_403928, EPI_ISL_403929, EPI_ISL_403930, EPI_ISL_403931, EPI_ISL_403932, EPI_ISL_403933, EPI_ISL_403934, EPI_ISL_403935, EPI_ISL_403936, EPI_ISL_403937, EPI_ISL_403962, EPI_ISL_403963, EPI_ISL_404227, EPI_ISL_404228, EPI_ISL_404253, EPI_ISL_404895, EPI_ISL_405839, EPI_ISL_406030, EPI_ISL_406031, EPI_ISL_406034, EPI_ISL_406036, EPI_ISL_406223, EPI_ISL_406531, EPI_ISL_406533, EPI_ISL_406534, EPI_ISL_406535, EPI_ISL_406536, EPI_ISL_406538, EPI_ISL_406592, EPI_ISL_406593, EPI_ISL_406594, EPI_ISL_406595, EPI_ISL_406596, EPI_ISL_406597, EPI_ISL_406798, EPI_ISL_406800, EPI_ISL_406801, EPI_ISL_406844, EPI_ISL_406862, EPI_ISL_406716, EPI_ISL_406717, EPI_ISL_406970, EPI_ISL_406973, EPI_ISL_407071, EPI_ISL_407073, EPI_ISL_407079, EPI_ISL_407084, EPI_ISL_407193, EPI_ISL_407214, EPI_ISL_407215, EPI_ISL_407313, EPI_ISL_407893, EPI_ISL_407894, EPI_ISL_407896, EPI_ISL_407976, EPI_ISL_407987, EPI_ISL_407988, EPI_ISL_408008, EPI_ISL_408009, EPI_ISL_408010, EPI_ISL_408430, EPI_ISL_408431, EPI_ISL_408478, EPI_ISL_408479, EPI_ISL_408480, EPI_ISL_408481, EPI_ISL_408482, EPI_ISL_408484, EPI_ISL_408486, EPI_ISL_408488, EPI_ISL_408489, EPI_ISL_408514, EPI_ISL_408515, EPI_ISL_408665, EPI_ISL_408666, EPI_ISL_408667, EPI_ISL_408668, EPI_ISL_408669, EPI_ISL_408670, EPI_ISL_408976, EPI_ISL_408977, EPI_ISL_409067, EPI_ISL_410044, EPI_ISL_410045, EPI_ISL_410218, EPI_ISL_410301, EPI_ISL_410486, EPI_ISL_410531, EPI_ISL_410532, EPI_ISL_410535, EPI_ISL_410536, EPI_ISL_410537, EPI_ISL_410538, EPI_ISL_410539, EPI_ISL_410540, EPI_ISL_410541, EPI_ISL_410542, EPI_ISL_410713, EPI_ISL_410714, EPI_ISL_410715, EPI_ISL_410716, EPI_ISL_410717, EPI_ISL_410718, EPI_ISL_410719, EPI_ISL_410720, EPI_ISL_410984, EPI_ISL_411060, EPI_ISL_411066, EPI_ISL_411218, EPI_ISL_411219, EPI_ISL_411220, EPI_ISL_411902, EPI_ISL_411915, EPI_ISL_411926, EPI_ISL_411927, EPI_ISL_411929, EPI_ISL_411950, EPI_ISL_411951, EPI_ISL_411952, EPI_ISL_411953, EPI_ISL_411954, EPI_ISL_411955, EPI_ISL_411956, EPI_ISL_411957, EPI_ISL_412026, EPI_ISL_412028, EPI_ISL_412029, EPI_ISL_412030, EPI_ISL_412459, EPI_ISL_412862, EPI_ISL_412869, EPI_ISL_412870, EPI_ISL_412871, EPI_ISL_412872, EPI_ISL_412873, EPI_ISL_412898, EPI_ISL_412899, EPI_ISL_412912, EPI_ISL_412966, EPI_ISL_412967, EPI_ISL_412968, EPI_ISL_412969, EPI_ISL_412970, EPI_ISL_412972, EPI_ISL_412973, EPI_ISL_412974, EPI_ISL_412975, EPI_ISL_412978, EPI_ISL_412979, EPI_ISL_412980, EPI_ISL_412981, EPI_ISL_412982, EPI_ISL_412983, EPI_ISL_413014, EPI_ISL_413015, EPI_ISL_413016, EPI_ISL_413017, EPI_ISL_413018, EPI_ISL_413021, EPI_ISL_413022, EPI_ISL_413023, EPI_ISL_413024, EPI_ISL_413213, EPI_ISL_413214, EPI_ISL_413455, EPI_ISL_413456, EPI_ISL_413457, EPI_ISL_413458, EPI_ISL_413459, EPI_ISL_413485, EPI_ISL_413486, EPI_ISL_413488, EPI_ISL_413489, EPI_ISL_413490, EPI_ISL_413513, EPI_ISL_413514, EPI_ISL_413515, EPI_ISL_413516, EPI_ISL_413518, EPI_ISL_413519, EPI_ISL_413520, EPI_ISL_413521, EPI_ISL_413522, EPI_ISL_413523, EPI_ISL_413555, EPI_ISL_413557, EPI_ISL_413558, EPI_ISL_413559, EPI_ISL_413560, EPI_ISL_413562, EPI_ISL_413563, EPI_ISL_413566, EPI_ISL_413572, EPI_ISL_413573, EPI_ISL_413577, EPI_ISL_413579, EPI_ISL_413580, EPI_ISL_413581, EPI_ISL_413582, EPI_ISL_413583, EPI_ISL_413584, EPI_ISL_413587, EPI_ISL_413589, EPI_ISL_413590, EPI_ISL_413591, EPI_ISL_413592, EPI_ISL_413593, EPI_ISL_413594, EPI_ISL_413595, EPI_ISL_413596, EPI_ISL_413597, EPI_ISL_413598, EPI_ISL_413599, EPI_ISL_413600, EPI_ISL_413602, EPI_ISL_413603, EPI_ISL_413604, EPI_ISL_413606, EPI_ISL_413607, EPI_ISL_413608, EPI_ISL_413609, EPI_ISL_413610, EPI_ISL_413611, EPI_ISL_413612, EPI_ISL_413613, EPI_ISL_413614, EPI_ISL_413615, EPI_ISL_413616, EPI_ISL_413617, EPI_ISL_413618, EPI_ISL_413619, EPI_ISL_413620, EPI_ISL_413621, EPI_ISL_413622, EPI_ISL_413647, EPI_ISL_413648, EPI_ISL_413691, EPI_ISL_413692, EPI_ISL_413693, EPI_ISL_413694, EPI_ISL_413697, EPI_ISL_413711, EPI_ISL_413729, EPI_ISL_413746, EPI_ISL_413748, EPI_ISL_413749, EPI_ISL_413750, EPI_ISL_413751, EPI_ISL_413761, EPI_ISL_413791, EPI_ISL_413809, EPI_ISL_413852, EPI_ISL_413853, EPI_ISL_413854, EPI_ISL_413856, EPI_ISL_413857, EPI_ISL_413858, EPI_ISL_413860, EPI_ISL_413861, EPI_ISL_413862, EPI_ISL_413863, EPI_ISL_413928, EPI_ISL_413931, EPI_ISL_413996, EPI_ISL_413997, EPI_ISL_413999, EPI_ISL_414005, EPI_ISL_414006, EPI_ISL_414007, EPI_ISL_414008, EPI_ISL_414009, EPI_ISL_414011, EPI_ISL_414012, EPI_ISL_414019, EPI_ISL_414020, EPI_ISL_414021, EPI_ISL_414022, EPI_ISL_414023, EPI_ISL_414027, EPI_ISL_414040, EPI_ISL_414041, EPI_ISL_414042, EPI_ISL_414043, EPI_ISL_414044, EPI_ISL_414045, EPI_ISL_414363, EPI_ISL_414366, EPI_ISL_414367, EPI_ISL_414368, EPI_ISL_414369, EPI_ISL_414414, EPI_ISL_414423, EPI_ISL_414428, EPI_ISL_414429, EPI_ISL_414433, EPI_ISL_414435, EPI_ISL_414439, EPI_ISL_414443, EPI_ISL_414445, EPI_ISL_414446, EPI_ISL_414451, EPI_ISL_414457, EPI_ISL_414468, EPI_ISL_414470, EPI_ISL_414476, EPI_ISL_414477, EPI_ISL_414479, EPI_ISL_414480, EPI_ISL_414481, EPI_ISL_414482, EPI_ISL_414483, EPI_ISL_414484, EPI_ISL_414485, EPI_ISL_414487, EPI_ISL_414500, EPI_ISL_414505, EPI_ISL_414509, EPI_ISL_414510, EPI_ISL_414511, EPI_ISL_414517, EPI_ISL_414519, EPI_ISL_414520, EPI_ISL_414521, EPI_ISL_414522, EPI_ISL_414523, EPI_ISL_414524, EPI_ISL_414525, EPI_ISL_414526, EPI_ISL_414527, EPI_ISL_414528, EPI_ISL_414529, EPI_ISL_414530, EPI_ISL_414531, EPI_ISL_414532, EPI_ISL_414534, EPI_ISL_414535, EPI_ISL_414545, EPI_ISL_414546, EPI_ISL_414547, EPI_ISL_414548, EPI_ISL_414549, EPI_ISL_414552, EPI_ISL_414554, EPI_ISL_414555, EPI_ISL_414556, EPI_ISL_414557, EPI_ISL_414558, EPI_ISL_414559, EPI_ISL_414560, EPI_ISL_414561, EPI_ISL_414562, EPI_ISL_414564, EPI_ISL_414565, EPI_ISL_414566, EPI_ISL_414569, EPI_ISL_414571, EPI_ISL_414574, EPI_ISL_414577, EPI_ISL_414578, EPI_ISL_414579, EPI_ISL_414580, EPI_ISL_414586, EPI_ISL_414587, EPI_ISL_414588, EPI_ISL_414589, EPI_ISL_414590, EPI_ISL_414591, EPI_ISL_414592, EPI_ISL_414593, EPI_ISL_414594, EPI_ISL_414595, EPI_ISL_414596, EPI_ISL_414597, EPI_ISL_414600, EPI_ISL_414601, EPI_ISL_414616, EPI_ISL_414617, EPI_ISL_414618, EPI_ISL_414619, EPI_ISL_414620, EPI_ISL_414621, EPI_ISL_414622, EPI_ISL_414623, EPI_ISL_414624, EPI_ISL_414625, EPI_ISL_414626, EPI_ISL_414627, EPI_ISL_414628, EPI_ISL_414629, EPI_ISL_414630, EPI_ISL_414631, EPI_ISL_414632, EPI_ISL_414633, EPI_ISL_414635, EPI_ISL_414637, EPI_ISL_414638, EPI_ISL_414641, EPI_ISL_414642, EPI_ISL_414643, EPI_ISL_414646, EPI_ISL_414648, EPI_ISL_414663, EPI_ISL_414684, EPI_ISL_414685, EPI_ISL_414686, EPI_ISL_414687, EPI_ISL_414688, EPI_ISL_414689, EPI_ISL_414690, EPI_ISL_414691, EPI_ISL_414692, EPI_ISL_414936, EPI_ISL_414937, EPI_ISL_414938, EPI_ISL_414940, EPI_ISL_414941, EPI_ISL_415105, EPI_ISL_415128, EPI_ISL_415129, EPI_ISL_415136, EPI_ISL_415141, EPI_ISL_415142, EPI_ISL_415147, EPI_ISL_415150, EPI_ISL_415151, EPI_ISL_415152, EPI_ISL_415153, EPI_ISL_415154, EPI_ISL_415155, EPI_ISL_415156, EPI_ISL_415157, EPI_ISL_415158, EPI_ISL_415159, EPI_ISL_415710, EPI_ISL_416426, EPI_ISL_416457, EPI_ISL_416481, EPI_ISL_416489, EPI_ISL_416491, EPI_ISL_416492, EPI_ISL_416514, EPI_ISL_416515, EPI_ISL_416516, EPI_ISL_416517, EPI_ISL_416518, EPI_ISL_416538, EPI_ISL_416539, EPI_ISL_416683, EPI_ISL_416685, EPI_ISL_416704, EPI_ISL_416711, EPI_ISL_416713, EPI_ISL_416715, EPI_ISL_416717, EPI_ISL_416744, EPI_ISL_416830, EPI_ISL_416831, EPI_ISL_416832, EPI_ISL_417020, EPI_ISL_417021, EPI_ISL_417022, EPI_ISL_417023, EPI_ISL_417024, EPI_ISL_417025, EPI_ISL_417026, EPI_ISL_417027, EPI_ISL_417028, EPI_ISL_417034, EPI_ISL_417200, EPI_ISL_417201, EPI_ISL_417202, EPI_ISL_417203, EPI_ISL_417204, EPI_ISL_417374, EPI_ISL_417375, EPI_ISL_417376, EPI_ISL_417377, EPI_ISL_417379, EPI_ISL_417382, EPI_ISL_417408, EPI_ISL_417409, EPI_ISL_417410, EPI_ISL_417411, EPI_ISL_417412, EPI_ISL_417413, EPI_ISL_417420, EPI_ISL_417435, EPI_ISL_417436, EPI_ISL_417437, EPI_ISL_417438, EPI_ISL_417439, EPI_ISL_417440, EPI_ISL_417441, EPI_ISL_417442, EPI_ISL_417467, EPI_ISL_417468, EPI_ISL_417504, EPI_ISL_417505, EPI_ISL_417506, EPI_ISL_417507, EPI_ISL_417508, EPI_ISL_417509, EPI_ISL_417510, EPI_ISL_417512, EPI_ISL_417513, EPI_ISL_417514, EPI_ISL_417515, EPI_ISL_417516, EPI_ISL_417517, EPI_ISL_417526, EPI_ISL_417527, EPI_ISL_417528, EPI_ISL_417529, EPI_ISL_417530, EPI_ISL_417531, EPI_ISL_417532, EPI_ISL_417533, EPI_ISL_417534, EPI_ISL_417536, EPI_ISL_417537, EPI_ISL_417538, EPI_ISL_417539, EPI_ISL_417540, EPI_ISL_417541, EPI_ISL_417542, EPI_ISL_417543, EPI_ISL_417544, EPI_ISL_417545, EPI_ISL_417546, EPI_ISL_417547, EPI_ISL_417548, EPI_ISL_417550, EPI_ISL_417551, EPI_ISL_417552, EPI_ISL_417553, EPI_ISL_417554, EPI_ISL_417555, EPI_ISL_417556, EPI_ISL_417557, EPI_ISL_417558, EPI_ISL_417559, EPI_ISL_417560, EPI_ISL_417561, EPI_ISL_417562, EPI_ISL_417563, EPI_ISL_417564, EPI_ISL_417565, EPI_ISL_417566, EPI_ISL_417567, EPI_ISL_417568, EPI_ISL_417569, EPI_ISL_417570, EPI_ISL_417571, EPI_ISL_417572, EPI_ISL_417573, EPI_ISL_417574, EPI_ISL_417575, EPI_ISL_417576, EPI_ISL_417577, EPI_ISL_417578, EPI_ISL_417579, EPI_ISL_417580, EPI_ISL_417581, EPI_ISL_417582, EPI_ISL_417583, EPI_ISL_417584, EPI_ISL_417585, EPI_ISL_417586, EPI_ISL_417587, EPI_ISL_417588, EPI_ISL_417589, EPI_ISL_417590, EPI_ISL_417591, EPI_ISL_417592, EPI_ISL_417593, EPI_ISL_417594, EPI_ISL_417595, EPI_ISL_417596, EPI_ISL_417597, EPI_ISL_417598, EPI_ISL_417599, EPI_ISL_417600, EPI_ISL_417601, EPI_ISL_417602, EPI_ISL_417603, EPI_ISL_417604, EPI_ISL_417605, EPI_ISL_417606, EPI_ISL_417607, EPI_ISL_417608, EPI_ISL_417609, EPI_ISL_417610, EPI_ISL_417611, EPI_ISL_417612, EPI_ISL_417613, EPI_ISL_417614, EPI_ISL_417615, EPI_ISL_417616, EPI_ISL_417617, EPI_ISL_417618, EPI_ISL_417619, EPI_ISL_417620, EPI_ISL_417621, EPI_ISL_417622, EPI_ISL_417623, EPI_ISL_417624, EPI_ISL_417625, EPI_ISL_417626, EPI_ISL_417627, EPI_ISL_417628, EPI_ISL_417629, EPI_ISL_417630, EPI_ISL_417631, EPI_ISL_417632, EPI_ISL_417633, EPI_ISL_417634, EPI_ISL_417635, EPI_ISL_417636, EPI_ISL_417637, EPI_ISL_417638, EPI_ISL_417639, EPI_ISL_417640, EPI_ISL_417641, EPI_ISL_417642, EPI_ISL_417643, EPI_ISL_417644, EPI_ISL_417645, EPI_ISL_417646, EPI_ISL_417647, EPI_ISL_417648, EPI_ISL_417649, EPI_ISL_417650, EPI_ISL_417651, EPI_ISL_417652, EPI_ISL_417653, EPI_ISL_417654, EPI_ISL_417666, EPI_ISL_417667, EPI_ISL_417668, EPI_ISL_417669, EPI_ISL_417670, EPI_ISL_417671, EPI_ISL_417672, EPI_ISL_417676, EPI_ISL_417678, EPI_ISL_417680, EPI_ISL_417685, EPI_ISL_417699, EPI_ISL_417700, EPI_ISL_417703, EPI_ISL_417706, EPI_ISL_417709, EPI_ISL_417712, EPI_ISL_417716, EPI_ISL_417717, EPI_ISL_417724, EPI_ISL_417733, EPI_ISL_417737, EPI_ISL_417740, EPI_ISL_417742, EPI_ISL_417743, EPI_ISL_417746, EPI_ISL_417750, EPI_ISL_417752, EPI_ISL_417753, EPI_ISL_417754, EPI_ISL_417762, EPI_ISL_417763, EPI_ISL_417764, EPI_ISL_417766, EPI_ISL_417774, EPI_ISL_417808, EPI_ISL_417809, EPI_ISL_417813, EPI_ISL_417814, EPI_ISL_417815, EPI_ISL_417816, EPI_ISL_417818, EPI_ISL_417819, EPI_ISL_417820, EPI_ISL_417821, EPI_ISL_417822, EPI_ISL_417823, EPI_ISL_417824, EPI_ISL_417825, EPI_ISL_417826, EPI_ISL_417827, EPI_ISL_417829, EPI_ISL_417830, EPI_ISL_417831, EPI_ISL_417832, EPI_ISL_417833, EPI_ISL_417834, EPI_ISL_417835, EPI_ISL_417836, EPI_ISL_417837, EPI_ISL_417838, EPI_ISL_417839, EPI_ISL_417864, EPI_ISL_417917, EPI_ISL_417918, EPI_ISL_417920, EPI_ISL_417925, EPI_ISL_417926, EPI_ISL_417931, EPI_ISL_417932, EPI_ISL_417933, EPI_ISL_417935, EPI_ISL_417936, EPI_ISL_417937, EPI_ISL_417938, EPI_ISL_417939, EPI_ISL_417940, EPI_ISL_417941, EPI_ISL_417942, EPI_ISL_417943, EPI_ISL_417944, EPI_ISL_417945, EPI_ISL_417946, EPI_ISL_417947, EPI_ISL_417948, EPI_ISL_417949, EPI_ISL_417950, EPI_ISL_417951, EPI_ISL_417953, EPI_ISL_417955, EPI_ISL_417958, EPI_ISL_417959, EPI_ISL_417960, EPI_ISL_417962, EPI_ISL_417964, EPI_ISL_417965, EPI_ISL_417966, EPI_ISL_417968, EPI_ISL_417970, EPI_ISL_417971, EPI_ISL_417973, EPI_ISL_417974, EPI_ISL_417976, EPI_ISL_417977, EPI_ISL_417982, EPI_ISL_417983, EPI_ISL_417984, EPI_ISL_417985, EPI_ISL_418009, EPI_ISL_418017, EPI_ISL_418018, EPI_ISL_418019, EPI_ISL_418020, EPI_ISL_418021, EPI_ISL_418022, EPI_ISL_418023, EPI_ISL_418024, EPI_ISL_418025, EPI_ISL_418026, EPI_ISL_418027, EPI_ISL_418029, EPI_ISL_418030, EPI_ISL_418031, EPI_ISL_418032, EPI_ISL_418033, EPI_ISL_418034, EPI_ISL_418037, EPI_ISL_418038, EPI_ISL_418040, EPI_ISL_418046, EPI_ISL_418047, EPI_ISL_418048, EPI_ISL_418050, EPI_ISL_418052, EPI_ISL_418053, EPI_ISL_418054, EPI_ISL_418063, EPI_ISL_418064, EPI_ISL_418067, EPI_ISL_418071, EPI_ISL_418072, EPI_ISL_418073, EPI_ISL_418074, EPI_ISL_418075, EPI_ISL_418076, EPI_ISL_418077, EPI_ISL_418078, EPI_ISL_418079, EPI_ISL_418080, EPI_ISL_418081, EPI_ISL_418082, EPI_ISL_418101, EPI_ISL_418102, EPI_ISL_418103, EPI_ISL_418104, EPI_ISL_418105, EPI_ISL_418126, EPI_ISL_418127, EPI_ISL_418128, EPI_ISL_418129, EPI_ISL_418130, EPI_ISL_418131, EPI_ISL_418132, EPI_ISL_418133, EPI_ISL_418134, EPI_ISL_418135, EPI_ISL_418136, EPI_ISL_418137, EPI_ISL_418138, EPI_ISL_418139, EPI_ISL_418140, EPI_ISL_418148, EPI_ISL_418149, EPI_ISL_418150, EPI_ISL_418151, EPI_ISL_418152, EPI_ISL_418153, EPI_ISL_418154, EPI_ISL_418155, EPI_ISL_418156, EPI_ISL_418157, EPI_ISL_418158, EPI_ISL_418159, EPI_ISL_418160, EPI_ISL_418161, EPI_ISL_418162, EPI_ISL_418163, EPI_ISL_418164, EPI_ISL_418165, EPI_ISL_418183, EPI_ISL_418184, EPI_ISL_418185, EPI_ISL_418186, EPI_ISL_418187, EPI_ISL_418188, EPI_ISL_418189, EPI_ISL_418190, EPI_ISL_418191, EPI_ISL_418192, EPI_ISL_418193, EPI_ISL_418194, EPI_ISL_418195, EPI_ISL_418197, EPI_ISL_418198, EPI_ISL_418199, EPI_ISL_418200, EPI_ISL_418201, EPI_ISL_418202, EPI_ISL_418203, EPI_ISL_418204, EPI_ISL_418231, EPI_ISL_418232, EPI_ISL_418233, EPI_ISL_418235, EPI_ISL_418236, EPI_ISL_418237, EPI_ISL_418238, EPI_ISL_418239, EPI_ISL_418240, EPI_ISL_418257, EPI_ISL_418260, EPI_ISL_418263, EPI_ISL_418264, EPI_ISL_418265 or EPI_ISL_616802 (hCoV-19/Denmark/DCGC-3024/2020).

Exemplary SARS-CoV-2 coronaviruses can also be defined or identified by genetic information provided by GenBank Accession Numbers as provided in List B below.

List B: GenBank Accession Numbers of Different SARS-CoV-2 Isolates:

NC_045512, LC528232, LC528233, LC529905, MN908947, MN938384, MN938385, MN938386, MN938387, MN938388, MN938389, MN938390, MN970003, MN970004, MN975262, MN975263, MN975264, MN975265, MN975266, MN975267, MN975268, MN985325, MN988668, MN988669, MN994467, MN994468, MN996527, MN996528, MN996529, MN996530, MN996531, MN997409, MT007544, MT012098, MT019529, MT019530, MT019531, MT019532, MT019533, MT020880, MT020881, MT027062, MT027063, MT027064, MT039873, MT039887, MT039888, MT039890, MT044257, MT044258, MT049951, MT050493, MT066156, MT066175, MT066176, MT072688, MT093571, MT093631, MT106052, MT106053, MT106054, MT118835, MT121215, MT123290, MT123291, MT123292, MT123293, MT126808, MT135041, MT135042, MT135043, MT135044, MT152824, MT159705, MT159706, MT159707, MT159708, MT159709, MT159710, MT159711, MT159712, MT159713, MT159714, MT159715, MT159716, MT159717, MT159718, MT159719, MT159720, MT159721, MT159722, MT163716, MT163717, MT163718, MT163719, MT163720, MT163721, MT184907, MT184908, MT184909, MT184910, MT184911, MT184912, MT184913, MT188339, MT188340, MT188341, MT192759, MT192765, MT192772 or MT192773.

SARS-CoV-2 coronavirus has been attributed the NCBI Taxonomy ID (NCBI: txid or taxID): 2697049.

The term “antigenic peptide or protein of an nCoV-2019 coronavirus” or “antigenic peptide or protein of a SARS-CoV-2 coronavirus” relates to any peptide or protein that is (from) or is derived from a SARS-CoV-2 (nCoV-2019) coronavirus as defined above, but also to fragments, variants or derivatives thereof, preferably to immunogenic fragments or immunogenic variants thereof.

The term “immunogenic fragment” or “immunogenic variant” has to be understood as any fragment/variant of the corresponding SARS-CoV-2 (nCoV-2019) coronavirus antigen that is capable of raising an immune response in a subject. Preferably, intramuscular or intradermal administration of the nucleic acid of the first aspect results in expression of the encoded SARS-CoV-2 antigen (peptide or protein) in a subject.

The term “expression” as used herein refers to the production of a SARS-CoV-2 coronavirus peptide or protein, wherein said SARS-CoV-2 coronavirus peptide or protein is provided by a coding sequence of a nucleic acid of the first aspect. For example, “expression” of an RNA refers to production of a protein (e.g. after administration of said RNA to a cell or a subject) via translation of the RNA into a polypeptide, e.g. into a peptide or protein that is or is derived from a SARS-CoV-2 coronavirus. “Expression” of a DNA refers to production of a protein (e.g. after administration of said DNA to a cell or a subject) via transcription of the DNA into RNA and subsequent translation into a polypeptide, e.g. into a peptide or protein that is or is derived from a SARS-CoV-2 coronavirus. The term “expression” and the term “production” may be used interchangeably herein. Further, the term “expression” preferably relates to production of a certain peptide or protein upon administration of a nucleic acid to a cell or an organism. In embodiments, the nucleic acid is suitable for a vaccine, preferably a coronavirus vaccine. In preferred embodiments, the nucleic acid is suitable for a SARS-CoV-2 coronavirus vaccine.

In the context of the invention, any protein that is or is derived from a SARS-CoV-2 coronavirus may be used and may be suitably encoded by the coding sequence or the nucleic acid of the first aspect. It is further in the scope of the underlying invention, that the at least one antigenic peptide or protein may comprise or consist of a synthetically engineered or an artificial coronavirus peptide or protein. The term “synthetically engineered” coronavirus peptide or protein, or the term “artificial coronavirus peptide or protein” relates to a protein that does not occur in nature. Accordingly, an “artificial coronavirus peptide or protein” or a “synthetically engineered coronavirus peptide or protein” may for example differ in at least one amino acid compared to the natural coronavirus peptide or protein, and/or may comprise an additional heterologous peptide or protein element, and/or may be N-terminally or C-terminally extended or truncated.

In preferred embodiments, the nucleic acid comprises at least one coding sequence encoding at least one antigenic peptide or protein of SARS-CoV-2 coronavirus, or an immunogenic fragment or immunogenic variant thereof, wherein the at least one antigenic peptide or protein comprises at least one peptide or protein that is or is derived from a structural protein, an accessory protein, or a replicase protein or an immunogenic fragment or immunogenic variant of any of these.

In preferred embodiments, the nucleic acid comprises at least one coding sequence encoding at least one antigenic peptide or protein of SARS-CoV-2 coronavirus, wherein the at least one antigenic peptide or protein comprises at least one peptide or protein that is or is derived from a structural protein, wherein the structural protein is selected from a spike protein (S), an envelope protein (E), a membrane protein (M) or a nucleocapsid protein (N), or an immunogenic fragment or variant of any of these.

In particularly preferred embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a spike protein (S), or an immunogenic fragment or immunogenic variant thereof.

Spike protein is a typical type I viral fusion protein that exists as trimer on the viral surface with each monomer consisting of a Head (S1) and stem (S2). Individual precursor S polypeptides form a homotrimer and undergo glycosylation within the Golgi apparatus as well as processing to remove the signal peptide, and cleavage by a cellular protease to generate separate S1 and S2 polypeptide chains, which remain associated as S1/S2 protomers within the homotrimer and is therefore a trimer of heterodimers. The S1 domain of the spike glycoprotein includes the receptor binding domain (RBD) that engages (most likely) with the angiotensin-converting enzyme 2 receptors and mediates viral fusion into the host cell, an N-terminal domain that may make initial contact with target cells, and 2 subdomains, all of which are susceptible to neutralizing antibodies. S2 domain consists of a six helix bundle fusion core involved in membrane fusion with the host endosomal membrane and is also a target for neutralization. The S2 subunit further comprises two heptad-repeat sequences (HR1 and HR2) and a central helix typical of fusion glycoproteins, a transmembrane domain, and the cytosolic tail domain.

Suitable antigenic peptide or protein sequences that are provided by the nucleic acid of the invention are disclosed in Table 1, rows 1 to 41, Column A and B. In addition, further information regarding said suitable antigenic peptide or protein sequences are provided under <223> identifier of the ST25 sequence listing.

In the following, preferred antigenic peptide or protein sequences that are provided by the nucleic acid of the invention are described in detail.

In preferred embodiments, the encoded at least one antigenic peptide or protein comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-111, 274-11663, 13176-13510, 13521-14123, 22732-22758, 22917, 22923, 22929-22964, 26938, 26939 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 1 to 41 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

It has to be noted that where reference is made to amino acid (aa) residues and their position in a spike protein (S), any numbering used herein—unless stated otherwise—relates to the position of the respective amino acid residue in a corresponding spike protein (S) of SARS-CoV-2 (nCoV-2019) coronavirus isolate EPI_ISL_402128 (BetaCoV_Wuhan_WIV05_2019_EPI_ISL_402128) according to SEQ ID NO: 1. Respective amino acid positions are, throughout the disclosure, exemplarily indicated for spike protein (S) of SARS-CoV-2 coronavirus isolate EPI_ISL_402128 (SEQ ID NO: 1). The person skilled in the art will of course be able to adapt the teaching provided in the present specification exemplified for SARS-CoV-2 EPI_ISL_402128 (SEQ ID NO: 1) to other antigenic peptides or proteins in other SARS-CoV-2 coronavirus isolates, e.g. to isolates including but not limited to EPI_ISL_404227, EPI_ISL_403963, EPI_ISL_403962, EPI_ISL_403931, EPI_ISL_403930, EPI_ISL_403929, EPI_ISL_402130, EPI_ISL_402129, EPI_ISL_402128, EPI_ISL_402126, EPI_ISL_402125, EPI_ISL_402124, EPI_ISL_402123, EPI_ISL_402120, EPI_ISL_402119 (further SARS-CoV-2 isolates are provided in List A and/or List B and or Table 25).

Protein annotation was performed using SEQ ID NO: 1 as a reference protein. The full-length spike protein (S) of SARS-CoV-2 coronavirus reference protein has 1273 amino acid residues, and comprises the following elements:

• 
  
  
  
  • secretory signal peptide: amino acid position aa 1 to aa 15 (see SEQ ID NO: 28)
  
  
  • spike protein fragment S1: amino acid position aa 1 to aa 681 (see SEQ ID NO: 27)
  
  
  • receptor binding domain (RBD): amino acid position aa 319 to aa 541 (see SEQ ID NO: 13243)
  
  
  • critical neutralisation domain (CND): amino acid position aa 329 to aa 529 (see SEQ ID NO: 13310)
  
  
  • spike protein fragment S2: amino acid position aa 682 to aa 1273 (see SEQ ID NO: 30)
  
  
  • transmembrane domain (TM) amino acid position aa 1212 to aa 1273 (see SEQ ID NO: 49)
  
  
  • transmembrane domain (TMflex) amino acid position aa 1148 to aa 1273 (see SEQ ID NO: 13176)
  
  
  
  

It has to be noted that variation on amino acid level naturally occurs between spike proteins derived from different SARS-CoV-2 isolates (exemplary SARS-CoV-2 isolates are provided in List A and List B). In the context of the invention, such amino acid variations can be applied to each antigenic peptide or protein derived from a spike protein as described herein.

Accordingly, each spike protein provided herein and contemplated as suitable antigen in the context of the invention may have one or more of the following amino acid variations (amino acid positions according to reference SEQ ID NO: 1):

• 
  
  
  
  • D614G or G614D
  
  
  • H49Y or Y49H
  
  
  • V367F or F367V
  
  
  • P1263L or L1263P
  
  
  • V483A or A483V
  
  
  • S939F or F939S
  
  
  • S943P or P943S
  
  
  • L5F or F5L
  
  
  • L8V or V8L
  
  
  • S940F or F940S
  
  
  • C1254F or F1254C
  
  
  • Q239K or K239Q
  
  
  • M153T or T153M
  
  
  • V1040F or F1040V
  
  
  • A845S or S845A
  
  
  • Y145H or H145Y
  
  
  • A831V or V831A
  
  
  • M1229I or I1229M
  
  
  • H69 or H69del/aa deleted
  
  
  • V70 or H70del/aa deleted
  
  
  • H69_V70 or H69del and H70del/aa deleted
  
  
  • A222V or V222A
  
  
  • Y453F or F453Y
  
  
  • S477N or N477S
  
  
  • I692V or V6921
  
  
  • R403K or K403R
  
  
  • K417N or N417K
  
  
  • N437S or S437N
  
  
  • N439K or K439N
  
  
  • V445A or A445V
  
  
  • V445I or I445V
  
  
  • V445F or F445V
  
  
  • G446V or V446G
  
  
  • G446S or S446G
  
  
  • G446A or A446G
  
  
  • L455F or F455L
  
  
  • F456L or L456F
  
  
  • K458N or N458K
  
  
  • A475V or V475A
  
  
  • G476S or S476G
  
  
  • G476A or A476G
  
  
  • S4771 or I477S
  
  
  • S477R or R477S
  
  
  • S477G or G477S
  
  
  • S477T or T477S
  
  
  • T478I or I478T
  
  
  • T478K or K478T
  
  
  • T478R or R478T
  
  
  • T478A or A478T
  
  
  • E484Q or Q484E
  
  
  • E484K or K484E
  
  
  • E484A or A484E
  
  
  • E484D or D484E
  
  
  • G485R or R485G
  
  
  • G485S or S485G
  
  
  • F486L or L486F
  
  
  • N487I or I487N
  
  
  • Y489H or H489Y
  
  
  • F490S or S490F
  
  
  • F490L or L490F
  
  
  • Q493L or L493Q
  
  
  • Q493K or K493Q
  
  
  • S494P or P494S
  
  
  • S494L or L494S
  
  
  • P499L or L499P
  
  
  • T500I or I500T
  
  
  • N501Y or Y501N
  
  
  • N501T or T501N
  
  
  • N501S or S501N
  
  
  • V503F or F503V
  
  
  • V503I or I503V
  
  
  • G504D or D504G
  
  
  • Y505W or W505Y
  
  
  • Q506K or K506Q
  
  
  • Q506H or H506Q
  
  
  • Y144 or Y144del/aa deleted
  
  
  • A570D or D570A
  
  
  • P681H or H681P
  
  
  • T716I or I716T
  
  
  • S982A or A982S
  
  
  • D1118H or H1118D
  
  
  • L18F or F18L
  
  
  • D80A or A80D
  
  
  • D215G or G215D
  
  
  • L242 or L242del/aa deleted
  
  
  • A243 or A243del/aa deleted
  
  
  • L244 or L244del/aa deleted
  
  
  • L242_A243_L244 or L242del and A243del and L244del/aa deleted
  
  
  • R246I or 1246R
  
  
  • A701V or V701A
  
  
  • T20N or N20T
  
  
  • P26S or S26P
  
  
  • D138Y or Y138D
  
  
  • R190S or S190R
  
  
  • H655Y or Y655H
  
  
  • T1027I or I1027T
  
  
  • S13I or I13S
  
  
  • W152C or C152W
  
  
  • L452R or R452L
  
  
  • R346T or T346R
  
  
  • P384L or L384P
  
  
  • L452M or M452L
  
  
  • F456A or A456F
  
  
  • F456K or K456F
  
  
  • F456V or V456F
  
  
  • E484P or P484E
  
  
  • K417T or T417K
  
  
  • G447V or V447G
  
  
  • L452Q or Q452L
  
  
  • A475S or S475A
  
  
  • F4861 or 1486F
  
  
  • F490Y or Y490F
  
  
  • Q493R or R493Q
  
  
  • S494A or A494S
  
  
  • P499H or H499P
  
  
  • P499S or S499P
  
  
  • G502V or V502G
  
  
  • T748K or K748T
  
  
  • A522S or S522A
  
  
  • V1176F or F1176V
  
  
  
  

The following amino acid variations (amino acid positions according to reference SEQ ID NO: 1) are particularly preferred:

• 
  
  
  
  • H69del, V70del, Y144del, N501Y, A570D, D614G, P681H, T716I, S982A, and D1118H
  
  
  • L18F, D80A, D215G, L242del, A243del, L244del, R246I, K417N, E484K, N501Y, D614G, and A701V
  
  
  • K417N, E484K, N501Y, and D614G
  
  
  • E484K and D614G
  
  
  • L18F, T20N, P26S, D138Y, R190S, K417T, E484K, N501Y, D614G, H655Y, and T1027I
  
  
  • S13I, W152C, L452R, and D614G
  
  
  • delH69, delV70, Y453F, D614G, I692V, and M1229I
  
  
  • E484K, E484P, or E484Q
  
  
  • G446V
  
  
  • G485R
  
  
  
  

In some embodiments, a fragment of a spike protein (S) may be encoded by the nucleic acid of the invention, wherein said fragment may be N-terminally truncated, lacking the N-terminal amino acids 1 to up to 100 of the full length SARS-CoV-2 coronavirus reference protein (SEQ ID NO: 1) and/or wherein said fragment may be C-terminally truncated, lacking the C-terminal amino acids (aa) 531 to up to aa 1273 of the full length SARS-CoV-2 coronavirus reference protein (SEQ ID NO: 1). Such “fragment of a spike protein (S)” may additionally comprise amino acid substitutions (as described below) and may additionally comprise at least one heterologous peptide or protein element (as described below). In preferred embodiments, a fragment of a spike protein (S) may be C-terminally truncated, thereby lacking the C-terminal transmembrane domain (that is, lacking aa 1212 to aa 1273 or lacking aa 1148 to aa 1273).

In other embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a spike protein (S), wherein the spike protein (S) derived from SARS-CoV-2 coronavirus lacks the transmembrane domain (TM) (amino acid position aa 1212 to aa 1273). In embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a spike protein (S), wherein the spike protein (S) derived from SARS-CoV-2 coronavirus lacks an extended part of the transmembrane domain (TMflex) (amino acid position aa 1148 to aa 1273). Without wishing to being bound to theory, a spike protein (S) lacking the transmembrane domain (TM or TMflex) as defined herein could be suitable for a coronavirus vaccine, as such a protein would be soluble and not anchored in the cell membrane. A soluble protein may therefore be produced (that is translated) in higher concentrations upon administration to a subject, leading to improved immune responses.

Without wishing to being bound to theory, RBD (aa 319 to aa 541) and CND (aa 29 to aa 529) domains may be crucial for immunogenicity. Both regions are located at the S1 fragment of the spike protein. Accordingly, it may be suitable in the context of the invention that the antigenic peptide or protein comprises or consists of an S1 fragment of the spike protein or an immunogenic fragment or immunogenic variant thereof. Suitably, such an S1 fragment may comprise at least an RBD and/or a CND domain as defined above.

In preferred embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a receptor-binding domain (RBD; aa 319 to aa 541), wherein the RBD comprises or consists of a spike protein fragment, or an immunogenic fragment or immunogenic variant thereof.

In further preferred embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a truncated receptor-binding domain (truncRBD; aa 334 to aa 528), wherein the RBD comprises or consists of a spike protein fragment, or an immunogenic fragment or immunogenic variant thereof.

Such “fragment of a spike protein (S)” (RBD; aa 319 to aa 541 or truncRBD, aa 334 to aa 528), may additionally comprise amino acid substitutions (as described below) and may additionally comprise at least one heterologous peptide or protein element (as described below).

In particularly preferred embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a spike protein (S), wherein the spike protein (S) comprises or consists of a spike protein fragment S1, or an immunogenic fragment or immunogenic variant thereof.

Accordingly, in preferred embodiments, the encoded at least one antigenic peptide or protein (comprising or consisting of a spike protein fragment S1) comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-27, 29, 31-48, 58-111, 274-1345, 1480-1546, 1614-11663, 13377-13510, 13521-14123, 22732, 22737-22758, 22929-22964 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 1 to 6, 9, 11-41 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In preferred embodiments, the encoded at least one antigenic peptide or protein comprises an spike protein fragment S1, and lacks at least 70%, 80%, 90%, preferably 100% of spike protein fragment S2 (aa 682 to aa 1273). Such embodiments may be beneficial, as the S1 fragment comprises neutralizing epitopes without potential problems of full-length protein comprising S1 and S2.

Accordingly, in preferred embodiments, the encoded at least one antigenic peptide or protein (essentially consisting of a spike protein fragment S1) comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 27, 1279-1345, 29, 1480-1546, 13243-13309, 22733-22736, 26938, 26939 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 6 and 9 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

Without wishing to being bound to theory, it may be suitable that the antigenic peptide or protein comprises or consists of spike protein fragment S1 and (at least a fragment of) spike protein fragment S2, because the formation of an immunogenic spike protein may be promoted.

Accordingly, in particularly preferred embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a spike protein (S), wherein the spike protein (S) comprises or consists of a spike protein fragment S1 or an immunogenic fragment or immunogenic variant thereof, and spike protein fragment S2 or an immunogenic fragment or immunogenic variant thereof.

In preferred embodiments, the at least one encoded antigenic peptide or protein that comprises or consists of spike protein fragment S1 and spike protein fragment S2, comprises at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 31-48, 58-111, 274-1278, 1614-11663, 13377-13510, 13521-14177, 22732, 22737-22758, 22929-22964 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 1 to 5, 11-35, 38 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In particularly preferred embodiments, the encoded at least one antigenic peptide or protein comprises or consists of a full-length spike protein or an immunogenic fragment or immunogenic variant of any of these.

The term “full length spike protein” has to be understood as a spike protein, preferably derived from a SARS-CoV-2 coronavirus, having an amino acid sequence corresponding to essentially the full spike protein. Accordingly, a “full length spike protein” may comprise aa 1 to aa 1273 (reference protein: SEQ ID NOs: 1). Accordingly, a full length spike protein may typically comprise a secretory signal peptide, a spike protein fragment S1, a spike protein fragment S2, a receptor binding domain (RBD), and a critical neutralisation domain CND, and a transmembrane domain. Notably, also variants that comprise certain amino acid substitutions (e.g. for allowing pre-fusion stabilization of the S protein) or natural occurring amino acid deletions are encompassed by the term “full length spike protein”.

Accordingly, in preferred embodiments, the at least one encoded antigenic peptide or protein is a full length S protein comprising or consisting of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-9, 274-340, 22737, 22739, 22741, 22743, 22745, 22747, 22749, 22751, 22753, 22755, 22757, 22929-22946 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see row 1 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In particularly preferred embodiments, the spike protein (S) that is provided by the nucleic acid of the first aspect is designed or adapted to stabilize the antigen in pre-fusion conformation. A pre-fusion conformation is particularly advantageous in the context of an efficient coronavirus vaccine, as several potential epitopes for neutralizing antibodies may merely be accessible in said pre-fusion protein conformation. Furthermore, remaining of the protein in the pre-fusion conformation is aimed to avoid immunopathological effects, like e.g. enhanced disease and/or antibody dependent enhancement (ADE).

In preferred embodiments, administration of a nucleic acid (or a composition or vaccine) encoding pre-fusion stabilized spike protein to a subject elicits spike protein neutralizing antibodies and does not elicit disease-enhancing antibodies. In particular, administration of a nucleic acid (or a composition or vaccine) encoding pre-fusion stabilized spike protein to a subject does not elicit immunopathological effects, like e.g. enhanced disease and/or antibody dependent enhancement (ADE).

Accordingly, in preferred embodiments, the nucleic acid of the invention comprises at least one coding sequence encoding at least one antigenic peptide or protein that is or is derived from an SARS-CoV-2 coronavirus, wherein the at least one antigenic peptide or protein is or is derived from a spike protein (S), wherein the spike protein (S) is a pre-fusion stabilized spike protein (S_stab). Suitably, said pre-fusion stabilized spike protein comprises at least one pre-fusion stabilizing mutation.

The term “pre-fusion conformation” as used herein relates to a structural conformation adopted by the ectodomain of the coronavirus S protein following processing into a mature coronavirus S protein in the secretory system, and prior to triggering of the fusogenic event that leads to transition of coronavirus S to the postfusion conformation.

A “pre-fusion stabilized spike protein (S_stab)” as described herein comprises one or more amino acid substitutions, deletions, or insertions compared to a native coronavirus S sequence that provide for increased retention of the prefusion conformation compared to coronavirus S ectodomain trimers formed from a corresponding native coronavirus S sequence. The “stabilization” of the prefusion conformation by the one or more amino acid substitutions, deletions, or insertions can be, for example, energetic stabilization (for example, reducing the energy of the prefusion conformation relative to the post-fusion open conformation) and/or kinetic stabilization (for example, reducing the rate of transition from the prefusion conformation to the postfusion conformation). Additionally, stabilization of the coronavirus S ectodomain trimer in the prefusion conformation can include an increase in resistance to denaturation compared to a corresponding native coronavirus S sequence.

Accordingly, in preferred embodiments, the spike protein includes one or more amino acid substitutions that stabilize the S protein in the pre-fusion conformation, for example, substitutions that stabilize the membrane distal portion of the S protein (including the N-terminal region) in the pre-fusion conformation.

Stabilization of the SARS-CoV-2 coronavirus spike protein may be obtained by substituting at least one amino acid at position K986 and/or V987 with amino acids that stabilize the spike protein in a perfusion conformation (amino acid positions according to reference SEQ ID NO: 1).

In particularly preferred embodiments, the pre-fusion stabilizing mutation comprises an amino acid substitution at position K986, wherein the amino acids K986 is substituted with one selected from A, I, L, M, F, V, G, or P (amino acid positions according to reference SEQ ID NO: 1), preferably wherein the amino acids K986 is substituted with P. In additionally preferred embodiments, the pre-fusion stabilizing mutation comprises an amino acid substitution at position K986, wherein the amino acids V987 is substituted with one selected from A, I, L, M, F, V, G, or P (amino acid positions according to reference SEQ ID NO: 1), preferably wherein the amino acids V987 is substituted with P.

Suitably, stabilization of the SARS-CoV-2 coronavirus spike protein may be obtained by substituting two consecutive amino acids at position K986 and V987 with amino acids that stabilize the spike protein in a prefusion conformation (Amino acid positions according to reference SEQ ID NO: 1).

In preferred embodiments, the pre-fusion stabilizing mutation comprises an amino acid substitution at position K986 and V987, wherein the amino acids K986 and/or V987 are substituted with one selected from A, I, L, M, F, V, G, or P (amino acid positions according to reference SEQ ID NO: 1).

Preferably, stabilization of the perfusion conformation is obtained by introducing two consecutive proline substitutions at residues K986 and V987 in the spike protein (Amino acid positions according to reference SEQ ID NO: 1).

Accordingly, in preferred embodiments, the pre-fusion stabilized spike protein (S_stab) comprises at least one pre-fusion stabilizing mutation, wherein the at least one pre-fusion stabilizing mutation comprises the following amino acid substitutions: K986P and V987P (amino acid positions according to reference SEQ ID NO: 1).

Accordingly, any NCBI Protein Accession numbers provided above, or any protein selected from SEQ ID NOs: 1-9, 274-340, 22737, 22739, 22741, 22743, 22745, 22747, 22749, 22751, 22753, 22755, 22757, 22929-22946 or fragments or variants thereof can be chosen by the skilled person to introduce such amino acid changes, preferably amino acid substitutions: K986P and V987P (amino acid positions according to reference SEQ ID NO: 1).

In preferred embodiments, the at least one pre-fusion stabilizing mutation comprises a cavity filling mutation that further stabilizes the pre-fusion state, wherein said mutation/amino acid substitution is selected from the list comprising T887WN; A1020W; T887WN and A1020W; or P1069F (amino acid positions according to reference SEQ ID NO: 1).

The term “cavity filling mutation” or “cavity filling amino acid substitutio” relates to an amino acid substitution that fills a cavity within the protein core of a protein, such as a coronavirus S protein ectodomain. Cavities are essentially voids within a folded protein where amino acids or amino acid side chains are not present. In several embodiments, a cavity-filling amino acid substitution is introduced to fill a cavity present in the prefusion conformation of a coronavirus S ectodomain core that collapses (e.g., has reduced volume) after transition to the postfusion conformation.

In some embodiments, at least one of the following amino acid substitutions F817P, A892P, A899P and A942P may be combined with a (K986P and V987P) substitution (amino acid positions according to reference SEQ ID NO: 1).

In preferred embodiments, the SARS-CoV-2 coronavirus spike protein comprises at least one of the following amino acid substitutions (Amino acid positions according to reference SEQ ID NO: 1):

• 
  
  
  
  • F817P; K986P and V987P
  
  
  • A892P; K986P and V987P
  
  
  • A899P; K986P and V987P
  
  
  • A942P; K986P and V987P
  
  
  
  

In particularly preferred embodiments, the SARS-CoV-2 coronavirus spike protein comprises the following amino acid substitutions (Amino acid positions according to reference SEQ ID NO: 1):

• 
  
  
  
  • F817P, A892P, A899P, A942P, K986P and V987P (S_stab_PP_hex)
  
  
  
  

Accordingly, any NCBI protein accession numbers provided above, or any protein selected from SEQ ID NOs: 1-9, 274-340, 22737, 22739, 22741, 22743, 22745, 22747, 22749, 22751, 22753, 22755, 22757, 22929-22946 or fragments or variants thereof can be chosen by the skilled person to introduce such amino acid changes, suitably amino acid substitutions selected from F817P, A892P, A899P, A942P; or amino acid substitutions selected from (F817P; K986P and V987P); (A892P; K986P and V987P); (A899P; K986P and V987P); (A942P; K986P and V987P); (F817P, A892P, A899P, A942P, K986P and V987P) (amino acid positions according to reference SEQ ID NO: 1).

In particularly preferred embodiments, at least one of the following amino acid substitutions T887W; A1020W; T887W and A1020W; or P1069F may be combined with a (K986P and V987P) substitution (amino acid positions according to reference SEQ ID NO: 1).

In other particularly preferred embodiments, the SARS-CoV-2 coronavirus spike protein comprises at least one of the following amino acid substitutions (Amino acid positions according to reference SEQ ID NO: 1):

• 
  
  
  
  • T887W; K986P and V987P
  
  
  • A1020W; K986P and V987P
  
  
  • T887W and A1020W; K986P and V987P
  
  
  • P1069F; K986P and V987P
  
  
  
  

Accordingly, any NCBI protein accession numbers provided above, or any protein selected from SEQ ID NOs: 1-9, 274-340, 22737, 22739, 22741, 22743, 22745, 22747, 22749, 22751, 22753, 22755, 22757, 22929-22946 or fragments or variants thereof can be chosen by the skilled person to introduce such amino acid changes, suitably amino acid substitutions selected from T887W; A1020W; T887W and A1020W; or P1069F; or amino acid substitutions selected from (T887W; K986P and V987P); (A1020W; K986P and V987P); (T887W and A1020W; K986P and V987P); (P1069F; K986P and V987P) (amino acid positions according to reference SEQ ID NO: 1).

In preferred embodiments, the at least one pre-fusion stabilizing mutation comprises a mutated protonation site that further stabilizes the pre-fusion state, wherein said mutation/amino acid substitution is selected from H1048Q and H1064N; H1083N and H1101N; or H1048Q and H1064N and H1083N and H1101N (amino acid positions according to reference SEQ ID NO: 1).

In some embodiments, at least one of the following amino acid substitutions H1048Q and H1064N; H1083N and H1101N; or H1048Q and H1064N and H1083N and H1101N may be combined with a (K986P and V987P) substitution (amino acid positions according to reference SEQ ID NO: 1).

In particularly preferred embodiments, the SARS-CoV-2 coronavirus spike protein comprises at least one of the following amino acid substitutions (Amino acid positions according to reference SEQ ID NO: 1):

• 
  
  
  
  • H1048Q and H1064N; K986P and V987P
  
  
  • H1083N and H1101N; K986P and V987P
  
  
  • H1048Q and H1064N and H1083N and H1101N; K986P and V987P
  
  
  
  

Accordingly, any NCBI protein accession numbers provided above, or any protein selected from SEQ ID NOs: 1-9, 274-340, 22737, 22739, 22741, 22743, 22745, 22747, 22749, 22751, 22753, 22755, 22757, 22929-22946 or fragments or variants thereof can be chosen by the skilled person to introduce such amino acid changes, suitably amino acid substitutions selected from H1048Q and H1064N; H1083N and H1101N; or H1048Q and H1064N and H1083N and H1101N; or amino acid substitutions selected from (H1048Q and H1064N; K986P and V987P); (H1083N and H1101N; K986P and V987P); (H1048Q and H1064N and H1083N and H1101N; K986P and V987P); (amino acid positions according to reference SEQ ID NO: 1).

In preferred embodiments, the at least one pre-fusion stabilizing mutation comprises an artificial intramolecular disulfide bond. Such an artificial intramolecular disulfide bond can be introduced to further stabilize the membrane distal portion of the S protein (including the N-terminal region) in the pre-fusion conformation; that is, in a conformation that specifically binds to one or more pre-fusion specification antibodies, and/or presents a suitable antigenic site that is present on the pre-fusion conformation but not in the post fusion conformation of the S protein.

In preferred embodiments, the at least one pre-fusion stabilizing mutation generates an artificial intramolecular disulfide bond, wherein the at least one artificial intramolecular disulfide bond is generated by at least two of the following amino acid substitutions selected from the list comprising I7120, I7140, P715C, T874C, G889C, A890C, I909C, N914C, Q965C, F970C, A972C, R995C, G999C, S1003C, L1034C, V1040C, Y1047C, S1055C, P1069C, T1077C, or Y1110C, S1123C (amino acid positions according to reference SEQ ID NO: 1).

In preferred embodiments, the at least one pre-fusion stabilizing mutation generates an artificial intramolecular disulfide bond, wherein the at least one artificial intramolecular disulfide bond is generated by at least one of the following amino acid substitutions: I7120 and T1077C; I7140 and Y1110C; P715C and P1069C; G889C and L1034C; I909C and Y1047C; Q965C and S1003C; F970C and G999C; A972C and R995C; A890C and V1040C; T874C and S1055C, or N914C and S1123C (amino acid positions according to reference SEQ ID NO: 1).

In further embodiments, the at least one pre-fusion stabilizing mutation comprises 2, 3, 4, 5, 6, 7, or 8 different artificial intramolecular disulfide bonds, wherein each may be selected from the following amino acid substitutions: I7120 and T1077C; I7140 and Y1110C; P715C and P1069C; G889C and L1034C; I909C and Y1047C; Q965C and S1003C; F970C and G999C; A972C and R995C; A890C and V1040C; T874C and S1055C, or N914C and S1123C (amino acid positions according to reference SEQ ID NO: 1).

In additional embodiments, at least one, preferably 2, 3, 4, 5 or more of the following amino acid substitutions I7120 and T1077C; I7140 and Y1110C; P715C and P1069C; G889C and L1034C; I909C and Y1047C; Q965C and S1003C; F970C and G999C; A972C and R995C; A890C and V1040C; T874C and S1055C, or N914C and S1123C may be combined with a (K986P and V987P) substitution. For example, a pre-fusion stabilized S protein may comprise two different artificial intramolecular disulfide bonds, e.g. I7120 and T1077C; P715C and P1069C; and additionally a K986P and V987P substitution, etc. (amino acid positions according to reference SEQ ID NO: 1).

In particularly preferred embodiments, the SARS-CoV-2 coronavirus spike protein comprises at least one of the following amino acid substitutions (amino acid positions according to reference SEQ ID NO: 1):

• 
  
  
  
  • I7120 and T1077C; K986P and V987P
  
  
  • I7140 and Y1110C; K986P and V987P
  
  
  • P715C and P1069C; K986P and V987P
  
  
  • G889C and L1034C; K986P and V987P
  
  
  • I909C and Y1047C; K986P and V987P
  
  
  • Q965C and S1003C; K986P and V987P
  
  
  • F970C and G999C; K986P and V987P
  
  
  • A972C and R995C; K986P and V987P
  
  
  • A890C and V1040C; K986P and V987P
  
  
  • T874C and S1055C; K986P and V987P
  
  
  • N914C and S1123C; K986P and V987P
  
  
  
  

Accordingly, any NCBI protein accession numbers provided above, or any protein selected from SEQ ID NOs: 1-9, 274-340, 22737, 22739, 22741, 22743, 22745, 22747, 22749, 22751, 22753, 22755, 22757, 22929-22946 or fragments or variants thereof can be chosen by the skilled person to introduce such amino acid changes, suitably amino acid substitutions selected from I7120 and T1077C; I7140 and Y1110C; P715C and P1069C; G889C and L1034C; I909C and Y1047C; Q965C and S1003C; F970C and G999C; A972C and R995C; A890C and V1040C; T874C and S1055C, or N914C and S1123C; or amino acid substitutions selected from (I712C; T1077C; K986P; V987P) or (I714C; Y1110C; K986P; V987P) or (P715C; P1069C; K986P; V987P) or (G889C; L1034C; K986P; V987P) or (I909C; Y1047C; K986P; V987P) or (Q965C; S1003C; K986P; V987P) or (F970C; G999C; K986P; V987P) or (A972C; R995C; K986P; V987P) or (A890C and V1040C; K986P and V987P) or (T874C and S1055C; K986P and V987P) or (N914C and S1123C; K986P and V987P) (amino acid positions according to reference SEQ ID NO: 1).

It has to be emphasized that in the context of the invention any SARS-CoV-2 coronavirus spike protein may be mutated as described above (exemplified for reference protein SEQ ID NO: 1) to stabilize the spike protein in the pre-fusion conformation.

Accordingly, in preferred embodiments, the pre-fusion stabilized spike protein (S_stab) comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10-26, 40-48, 85-111, 341-1278, 1681-2618, 2686-3623, 3691-4628, 4696-5633, 5701-6638, 6706-7643, 7711-8648, 8716-9653, 9721-10658, 10726-11663, 13377-13510, 13521-14123, 22732, 22738, 22740, 22742, 22744, 22746, 22748, 22750, 22752, 22754, 22756, 22758, 22947-22964 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 2 to 5, 12-15, 17-20, 22-25, 27-30, 32-35, 38 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In particularly preferred embodiments, the pre-fusion stabilized spike protein (S_stab) comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10-26, 341-407, 609-1278, 13521-13587, 22738, 22740, 22742, 22744, 22746, 22748, 22750, 22752, 22754, 22756, 22758, 22947-22964 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 2 and 5 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In a more preferred embodiment, the pre-fusion stabilized spike protein (S_stab) comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10-18, 341-407, 22947-22964 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see row 2 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In a further, more preferred embodiment, the pre-fusion stabilized spike protein (S_stab) comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22960, 22961, 22963 or an immunogenic fragment or immunogenic variant of any of these.

In an even more preferred embodiment, the pre-fusion stabilized spike protein (S_stab) comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10 or 341 or an immunogenic fragment or immunogenic variant of any of these.

According to various preferred embodiments, the nucleic acid of the invention encodes at least one antigenic peptide or protein from SARS-CoV-2 coronavirus as defined herein and, additionally, at least one heterologous peptide or protein element.

Suitably, the at least one heterologous peptide or protein element may promote or improve secretion of the encoded antigenic peptide or protein of the invention (e.g. via secretory signal sequences), promote or improve anchoring of the encoded antigenic peptide or protein of the invention in the plasma membrane (e.g. via transmembrane elements), promote or improve formation of antigen complexes (e.g. via multimerization domains or antigen clustering elements), or promote or improve virus-like particle formation (VLP forming sequence). In addition, the nucleic acid of the first aspect may additionally encode peptide linker elements, self-cleaving peptides, immunologic adjuvant sequences or dendritic cell targeting sequences.

Suitable multimerization domains may be selected from the list of amino acid sequences according to SEQ ID NOs: 1116-1167 of WO2017/081082, or fragments or variants of these sequences. Suitable transmembrane elements may be selected from the list of amino acid sequences according to SEQ ID NOs: 1228-1343 of WO2017/081082, or fragments or variants of these sequences. Suitable VLP forming sequences may be selected from the list of amino acid sequences according to SEQ ID NOs: 1168-1227 of the patent application WO2017/081082, or fragments or variants of these sequences. Suitable peptide linkers may be selected from the list of amino acid sequences according to SEQ ID NOs: 1509-1565 of the patent application WO2017/081082, or fragments or variants of these sequences. Suitable self-cleaving peptides may be selected from the list of amino acid sequences according to SEQ ID NOs: 1434-1508 of the patent application WO2017/081082, or fragments or variants of these sequences. Suitable immunologic adjuvant sequences may be selected from the list of amino acid sequences according to SEQ ID NOs: 1360-1421 of the patent application WO2017/081082, or fragments or variants of these sequences. Suitable dendritic cell (DCs) targeting sequences may be selected from the list of amino acid sequences according to SEQ ID NOs: 1344-1359 of the patent application WO2017/081082, or fragments or variants of these sequences. Suitable secretory signal peptides may be selected from the list of amino acid sequences according to SEQ ID NOs: 1-1115 and SEQ ID NO: 1728 of published PCT patent application WO2017/081082, or fragments or variants of these sequences In preferred embodiments, the at least one coding sequence additionally encodes one or more heterologous peptide or protein elements selected from a signal peptide, a linker peptide, a helper epitope, an antigen clustering element, a trimerization or multimerization element, a transmembrane element, or a VLP forming sequence.

In preferred embodiments, the nucleic acid of the invention encoding at least one antigenic protein derived from an SARS-CoV-2 coronavirus, additionally encodes at least one heterologous trimerization element, an antigen clustering element, or a VLP forming sequence.

Antigen Clustering Elements or Multimerization Elements

In preferred embodiments, the antigen clustering elements may be selected from a ferritin element, or a lumazine synthase element, surface antigen of Hepatitis B virus (HBsAg), or encapsulin. Expressing a stably clustered spike protein, preferably in in its prefusion conformation may increases the magnitude and breadth of neutralizing activity against SARS-CoV-2.

Lumazine synthase (Lumazine, LS, LumSynth) is an enzyme with particle-forming properties, present in a broad variety of organisms and involved in riboflavin biosynthesis.

In particularly preferred embodiments, lumazine synthase is used to promote antigen clustering and may therefore promote or enhance immune responses of the encoded coronavirus antigen of the invention.

In particularly preferred embodiments, the antigen clustering element (multimerization element) is or is derived from lumazine synthase, wherein the amino acid sequences of said antigen clustering domain is preferably identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of amino acid sequences SEQ ID NO: 112, a fragment or variant thereof.

Ferritin is a protein whose main function is intracellular iron storage. Almost all living organisms produce ferritin which is made of 24 subunits, each composed of a four-alpha-helix bundle, that self-assemble in a quaternary structure with octahedral symmetry. Its properties to self-assemble into nanoparticles are well-suited to carry and expose antigens.

In particularly preferred embodiments, ferritin is used to promote the antigen clustering and may therefore promote immune responses of the encoded coronavirus antigen, preferably spike protein.

In particularly preferred embodiments, the antigen clustering element (multimerization element) is or is derived from ferritin wherein the amino acid sequences of said antigen clustering domain is preferably identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of amino acid sequence SEQ ID NO: 113, a fragment or variant thereof.

In some embodiments, the antigen-clustering domain is a Hepatitis B surface antigen (HBsAg). HBsAg forms spherical particles. The addition of a fragment of the surface antigen of Hepatitis B virus (HBsAg) sequence may be particularly effective in enhancing the immune response of the nucleic-acid-based vaccine against coronavirus.

In particularly preferred embodiments, HBsAg is used to promote the antigen clustering and may therefore promote immune responses of the encoded coronavirus antigen, preferably a spike protein as defined herein.

In some embodiments, the antigen-clustering element is an encapsulin element. The addition of an encapsulin sequence may be particularly effective in enhancing the immune response of the nucleic-acid-based vaccine against coronavirus. In particularly preferred embodiments, encapsulin is used to promote the antigen clustering and may therefore promote immune responses of the encoded coronavirus antigen, preferably a spike protein as defined herein.

Encapsulin is a protein isolated from thermophile Thermotoga maritima and may be used as an element to allow self-assembly of antigens to form antigen (nano)particles. Encapsulin is assembled from 60 copies of identical 31 kDa monomers having a thin and icosahedral T=1 symmetric cage structure with interior and exterior diameters of 20 and 24 nm, respectively.

In some embodiments where the coding sequence of the nucleic acid additionally encodes heterologous antigen clustering element, it is particularly preferred and suitable to generate a fusion protein comprising an antigen-clustering element and an antigenic peptide or protein derived from SARS-CoV-2. Suitably, said antigenic peptide or protein, preferably the spike protein, is lacking the C-terminal transmembrane domain (TM) (lacking aa 1212 to aa 1273) or is lacking a part of the the C-terminal transmembrane domain (TMflex), e.g. lacking aa 1148 to aa 1273.

Accordingly, any amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 274-1278, 13521-13587, 22732, 22737-22758, 22929-22964 can be modified to remove the endogenous transmembrane domain (TM) at position aa 1212 to aa 1273 and may therefore be used as “C-terminally truncated” proteins in the context of the invention (Amino acid positions according to reference SEQ ID NO: 1). Furthermore, any amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 274-1278, 13521-13587, 22732, 22737-22758, 22929-22964 can be modified to remove a part the endogenous transmembrane domain (TMflex) at position aa 1148 to aa 1273 and may therefore be used as “C-terminally truncated” proteins in the context of the invention (Amino acid positions according to reference SEQ ID NO: 1). Suitable spike proteins lacking the C-terminal transmembrane domain (TM or TMflex) may be selected from SEQ ID NOs: 31-39, 1614-3623, 13377-13510.

In other embodiments, where the coding sequence of the nucleic acid additionally encodes heterologous antigen clustering element as defined above, it is particularly preferred and suitable to generate a fusion protein comprising an antigen clustering element and an antigenic peptide or protein derived from SARS-CoV-2 spike protein fragment S1 (lacking S2 and/or TM and/or TMflex). Further, it may be suitable to use linker elements for separating the heterologous antigen-clustering element from the antigenic peptide or protein (e.g. a linker according to SEQ ID NO: 115, 13148, 13152).

In preferred embodiments, the at least one antigenic peptide or protein comprising a heterologous antigen clustering element comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 58-75, 85-102, 3624-5633, 7644-9653, 13588-13721, 13856-13989, 22733, 22735, 22736 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 16 and 25 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

Further suitable multimerization elements may be selected from the list of amino acid sequences according to SEQ ID NOs: 1116-1167 of WO2017/081082, or fragments or variants of these sequences. SEQ ID NOs: 1116-1167 of WO2017/081082 are herewith incorporated by reference.

Trimerization Elements

In preferred embodiments, the trimerization element may be selected from a foldon element. In preferred embodiments, the foldon element is a fibritin foldon element. Expressing a stable trimeric spike protein, preferably in its prefusion conformation, may increases the magnitude and breadth of neutralizing activity against SARS-CoV-2.

In particularly preferred embodiments, a fibritin foldon element is used to promote the antigen trimerization and may therefore promote immune responses of the encoded coronavirus antigen, preferably spike protein. Preferably, the foldon element is or is derived from a bacteriophage, preferably from bacteriophage T4, most preferably from fibritin of bacteriophage T4.

In particularly preferred embodiments, the trimerization element is or is derived from foldon wherein the amino acid sequences of said trimerization element is preferably identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of amino acid sequence SEQ ID NO: 114, a fragment or variant of any of these.

In other embodiments where the coding sequence of the nucleic acid additionally encodes heterologous trimerization element, it is particularly preferred and suitable to generate a fusion protein comprising a trimerization element and an antigenic peptide or protein derived from SARS-CoV-2. Suitably, said antigenic peptide or protein, preferably the spike protein derived from SARS-CoV-2 that is lacking the C-terminal transmembrane domain (lacking aa 1212 to aa 1273), or is lacking a part of the the C-terminal transmembrane domain (TMflex), e.g. lacking aa 1148 to aa 1273.

Accordingly, any amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 274-1278, 13521-13587, 22732, 22737-22758, 22947-22964 can be modified to lack the endogenous transmembrane element at position aa 1212 to aa 1273 and may therefore be used as “C-terminally truncated” proteins in the context of the invention. Furthermore, any amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 274-1278, 13521-13587, 22732, 22737-22758, 22947-22964 can be modified to remove a part the endogenous transmembrane domain (TMflex) at position aa 1148 to aa 1273 and may therefore be used as “C-terminally truncated” proteins in the context of the invention (Amino acid positions according to reference SEQ ID NO: 1). Suitable spike proteins lacking the C-terminal transmembrane domain (TM or TMflex) may be selected from SEQ ID NOs: 31-39, 1614-3623, 13377-13510.

In other embodiments, where the coding sequence of the nucleic acid additionally encodes heterologous trimerization element as defined above, it is particularly preferred and suitable to generate a fusion protein comprising an trimerization element and an antigenic peptide or protein derived from SARS-CoV-2 spike protein fragment S1 (lacking S2 and/or TM and/or TMflex). Further, it may be suitable to use linker elements for separating the heterologous antigen-clustering element from the antigenic peptide or protein (e.g. a linker according to SEQ ID NO: 115, 13148, 13152).

In preferred embodiments, the at least one antigenic peptide or protein comprising a heterologous trimerization element comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 76-84, 103-111, 5634-6638, 9654-10658, 13722-13788, 13990-14056, 22734 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 26, 30, and 41 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

Further suitable trimerization elements may be selected from the list of amino acid sequences according to SEQ ID NOs: 1116-1167 of WO2017/081082, or fragments or variants of these sequences. SEQ ID NOs: 1116-1167 of WO2017/081082 are herewith incorporated by reference.

VLP Forming Elements

In preferred embodiments, the VLP forming sequence may be selected and fused to the coronavirus antigen as defined herein. Expressing a stably clustered spike protein in VLP form may increases the magnitude and breadth of neutralizing activity against SARS-CoV-2. VLPs structurally mimic infectious viruses and they can induce potent cellular and humoral immune responses.

Suitable VLP forming sequences may be selected from elements derived from Hepatitis B virus core antigen, HIV-1 Gag protein, or Woodchuck hepatitis core antigen element (WhcAg).

In particularly preferred embodiments, the at least one VLP-forming sequence is a Woodchuck hepatitis core antigen element (WhcAg). The WhcAg element is used to promote VLP formation and may therefore promote immune responses of the encoded coronavirus antigen, preferably spike protein.

In particularly preferred embodiments, the VLP forming sequence is or is derived from foldon wherein the amino acid sequences of said VLP forming sequences is preferably identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of amino acid sequence SEQ ID NO: 13171, a fragment or variant of any of these.

In further embodiments where the coding sequence of the nucleic acid additionally encodes heterologous VLP forming sequence, it is particularly preferred and suitable to generate a fusion protein comprising a VLP forming sequence and an antigenic peptide or protein derived from SARS-CoV-2. Suitably, said antigenic peptide or protein, preferably the spike protein derived from SARS-CoV-2 that is lacking the C-terminal transmembrane domain (lacking aa 1212 to aa 1273), or is lacking a part of the the C-terminal transmembrane domain (TMflex), e.g. lacking aa 1148 to aa 1273.

Accordingly, any amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 274-1278, 13521-13587, 22732, 22737-22758, 22929-22964 can be modified to lack the endogenous transmembrane element at position aa 1212 to aa 1273 and may therefore be used as “C-terminally truncated” proteins in the context of the invention. Furthermore, any amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 274-1278, 13521-13587, 22732, 22737-22758, 22929-22964 can be modified to remove a part the endogenous transmembrane domain (TMflex) at position aa 1148 to aa 1273 and may therefore be used as “C-terminally truncated” proteins in the context of the invention (Amino acid positions according to reference SEQ ID NO: 1).

Suitable spike proteins lacking the C-terminal transmembrane domain (TM or TMflex) may be selected from SEQ ID NOs: 31-39, 1614-3623, 13377-13510.

In other embodiments, where the coding sequence of the nucleic acid additionally encodes heterologous VLP-forming sequence as defined above, it is particularly preferred and suitable to generate a fusion protein comprising a VLP-forming sequence and an antigenic peptide or protein derived from SARS-CoV-2 spike protein fragment S1 (lacking S2 and/or TM and/or TMflex). Further, it may be suitable to use linker elements for separating the heterologous antigen-clustering element from the antigenic peptide or protein (e.g. a linker according to SEQ ID NO: 115, 13148, 13152).

In preferred embodiments, the at least one antigenic peptide or protein comprising a heterologous VLP-forming sequence comprises or consists of at least one of the amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 6639-7643, 10659-11663, 13789-13855, 14057-14123 or an immunogenic fragment or immunogenic variant of any of these. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 31 and 35 of Column A and B), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

Further suitable VLP forming sequences in that context may be selected from the list of amino acid sequences according to SEQ ID NOs: 1168-1227 of the patent application WO2017/081082, or fragments or variants of these sequences. SEQ ID NOs: 1168-1227 of WO2017/081082 are herewith incorporated by reference.

Heterologous Secretory Signal Peptides

In some embodiments, the antigenic peptide or protein comprises a heterologous signal peptide. A heterologous signal peptide may be used to improve the secretion of the encoded coronavirus antigen.

Suitable secretory signal peptides may be selected from the list of amino acid sequences according to SEQ ID NOs: 1-1115 and SEQ ID NO: 1728 of published PCT patent application WO2017/081082, or fragments or variants of these sequences. 1-1115 and SEQ ID NO: 1728 of WO2017/081082 are herewith incorporated by reference. In embodiments where the coding sequence of the nucleic acid additionally encodes heterologous secretory signal peptide, it is particularly preferred and suitable to generate a fusion protein comprising a heterologous secretory signal peptide and an antigenic peptide or protein derived from SARS-CoV-2. Suitably, said antigenic peptide or protein, preferably the spike protein derived from SARS-CoV-2 is lacking the N-terminal endogenous secretory signal peptide (lacking aa 1 to aa 15). Accordingly, any amino acid sequences being identical or at least 50%, 60%, 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-26, 274-1278, 13521-13587, 22732, 22737-22758, 22929-22964 can be modified to lack the endogenous secretory signal peptide at position aa 1 to aa 15 and may therefore be used as “N-terminally truncated” proteins in the context of the invention.

In the following List 1, suitable SARS-CoV-2 coronavirus antigenic peptides and proteins as defined above are further specified in detail (e.g. nomenclature, protein elements, etc.).

List 1: Exemplary Suitable Protein Designs of the Invention:

• 
  
  
  
  • Full length spike protein (S) comprising aa 1 to aa 1273;
    
    
    
    • see for example SEQ ID NO: 1, 274.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and K986P, V987P substitutions (S_stab_PP);
    
    
    
    • see for example SEQ ID NO: 10, 341.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and K986P, V987P substitutions (S_stab_PP);
    
    
    
    • see for example SEQ ID NO: 22961.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and K986P, V987P substitutions (S_stab_PP);
    
    
    
    • see for example SEQ ID NO: 22960.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and K986P, V987P, F817P, A892P, A899P, A942P proline substitutions; S_stab_PP_hex
    
    
    
    • see for example SEQ ID NO: 22732.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and K986P, V987P substitutions and a cavity filling mutation (T887W, A1020W); S_stab_PP_cav
    
    
    
    • see for example SEQ ID NO: 408.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and K986P, V987P substitutions and a cavity filling mutation (P1069F); S_stab_PP_cav
    
    
    
    • see for example SEQ ID NO: 475.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and K986P, V987P substitutions and a cavity filling mutation (H1048Q, H1064N, H1083N, H1101N); S_stab_PP_prot
    
    
    
    • see for example SEQ ID NO: 542.
    
    
    
    
  
  
  • Stabilized S protein comprising aa1-aa1273 and an artificial disulfide bond (S_stab_disul) I7120, T1077C;
    
    
    
    • see for example SEQ ID NO: 19, 609.
    
    
    
    
  
  
  • S without transmembrane domain comprising aa1-aa1211 (S_woTM);
    
    
    
    • see for example SEQ ID NO: 31, 1614.
    
    
    
    
  
  
  • S without transmembrane domain flex comprising aa1-aa1147 (S_woTMflex);
    
    
    
    • see for example SEQ ID NO: 2619.
    
    
    
    
  
  
  • S_woTM comprising K986P, V987P substitutions (S_stab_PP_woTM)
    
    
    
    • see for example SEQ ID NO: 40, 1681.
    
    
    
    
  
  
  • S_woTMflex comprising K986P, V987P substitutions (S_stab_PP_woTMflex)
    
    
    
    • see for example SEQ ID NO: 2686.
    
    
    
    
  
  
  • Spike protein fragment S1 comprising aa 1 to aa 681 (S1);
    
    
    
    • see for example SEQ ID NO: 27, 1279.
    
    
    
    
  
  
  • S_woTM comprising a lumazine synthase;
    
    
    
    • see for example SEQ ID NO: 58, 3624.
    
    
    
    
  
  
  • S_woTMflex comprising a lumazine synthase;
    
    
    
    • see for example SEQ ID NO: 7644.
    
    
    
    
  
  
  • S_stab_PP_woTM comprising a lumazine synthase;
    
    
    
    • see for example SEQ ID NO: 85, 3691.
    
    
    
    
  
  
  • S_stab_PP_woTMflex comprising a lumazine synthase;
    
    
    
    • see for example SEQ ID NO: 7711.
    
    
    
    
  
  
  • S_woTM comprising a ferritin element;
    
    
    
    • see for example SEQ ID NO: 67, 4629.
    
    
    
    
  
  
  • S_woTMflex comprising a ferritin element;
    
    
    
    • see for example SEQ ID NO: 8649.
    
    
    
    
  
  
  • S_stab_PP_woTM comprising a ferritin element;
    
    
    
    • see for example SEQ ID NO: 94, 4696.
    
    
    
    
  
  
  • S_stab_PP_woTMflex comprising a ferritin element;
    
    
    
    • see for example SEQ ID NO: 8716.
    
    
    
    
  
  
  • S_woTM comprising a foldon element;
    
    
    
    • see for example SEQ ID NO: 76, 5634.
    
    
    
    
  
  
  • S_woTMflex comprising a foldon element;
    
    
    
    • see for example SEQ ID NO: 9654.
    
    
    
    
  
  
  • S_stab_PP_woTM comprising a foldon element;
    
    
    
    • see for example SEQ ID NO: 103, 5701.
    
    
    
    
  
  
  • S_stab_PP_woTMflex comprising a foldon element;
    
    
    
    • see for example SEQ ID NO: 9721.
    
    
    
    
  
  
  • S_woTM comprising a VLP-sequence (WhcAg);
    
    
    
    • see for example SEQ ID NO: 6639.
    
    
    
    
  
  
  • S_woTMflex comprising a VLP-sequence (WhcAg);
    
    
    
    • see for example SEQ ID NO 10659.
    
    
    
    
  
  
  • S_stab_PP_woTM comprising a VLP-sequence (WhcAg);
    
    
    
    • see for example SEQ ID NO: 6706.
    
    
    
    
  
  
  • S_stab_PP_woTMflex comprising a VLP-sequence (WhcAg);
    
    
    
    • see for example SEQ ID NO: 10726.
    
    
    
    
  
  
  • truncRBD comprising a foldon element:
    
    
    
    • see for example SEQ ID NO: 22734.
    
    
    
    
  
  
  • truncRBD comprising a lumazine synthase (C-terminal)
    
    
    
    • see for example SEQ ID NO: 22735.
    
    
    
    
  
  
  • truncRBD comprising a lumazine synthase (N-terminal)
    
    
    
    • see for example SEQ ID NO: 22736
    
    
    
    
  
  
  • truncRBD comprising a ferritin element:
    
    
    
    • see for example SEQ ID NO: 22733.
    
    
    
    
  
  
  
  

Amino acid positions provided in List 1 are according to reference SEQ ID NO: 1.

In particularly preferred embodiments of the first aspect, the at least one antigenic peptide or protein comprises or consists of at least one of the amino acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10, 21, 22, 25, 27, 274, 341, 408, 475, 542, 743, 810, 1011, 1145, 1212, 1279, 8716, 10726, 22732-22758, 22929-22942, 22947-22964 or an immunogenic fragment or immunogenic variant of any of these.

Preferred antigenic peptide or proteins derived from an SARS-CoV-2 coronavirus as defined above are provided in Table 1 (rows 1 to 41). Therein, each row 1 to 41 corresponds to a suitable SARS-CoV-2 coronavirus constructs. Column A of Table 1 provides a short description of suitable antigen constructs. Column B of Table 1 provides protein (amino acid) SEQ ID NOs of respective antigen constructs. Column C of Table 1 provides SEQ ID NO of the corresponding wild type nucleic acid coding sequences. Column D of Table 1 provides SEQ ID NO of the corresponding G/C optimized nucleic acid coding sequences (opt1, gc). Column E of Table 1 provides SEQ ID NO of the corresponding human codon usage adapted nucleic acid coding sequences (opt 3, human). Column F of Table 1 provides SEQ ID NO of the corresponding G/C content modified nucleic acid coding sequences (opt10, gc mod) (for a detailed description of “coding sequences”, see paragraph “suitable coding sequences”).

Notably, the description of the invention explicitly includes the information provided under <223> identifier of the ST25 sequence listing of the present application. Preferred nucleic acid constructs comprising coding sequences of Table 1, e.g. mRNA sequences comprising the coding sequences of Table 1 are provided in Table 3a and Table 3b.

Suitable Coding Sequences:

According to preferred embodiments, the nucleic acid of the invention comprises at least one coding sequence encoding at least one antigenic peptide or protein derived from SARS-CoV-2 (nCoV-2019) coronavirus, preferably as defined above, or fragments and variants thereof. In that context, any coding sequence encoding at least one antigenic protein as defined herein, or fragments and variants thereof may be understood as suitable coding sequence and may therefore be comprised in the nucleic acid of the invention.

In preferred embodiments, the nucleic acid of the first aspect may comprise or consist of at least one coding sequence encoding at least one antigenic peptide or protein from SARS-CoV-2 coronavirus as defined herein, preferably encoding any one of SEQ ID NOs: 1-111, 274-11663, 13176-13510, 13521-14123, 22732-22758, 22917, 22923, 22929-22964, 26938, 26939 or fragments of variants thereof. It has to be understood that, on nucleic acid level, any sequence (DNA or RNA sequence) which encodes an amino acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 1-111, 274-11663, 13176-13510, 13521-14123, 22732-22758, 22917, 22923, 22929-22964, 26938, 26939 or fragments or variants thereof, may be selected and may accordingly be understood as suitable coding sequence of the invention. Further information regarding said amino acid sequences is also provided in Table 1 (see rows 1 to 41 of Column A and B), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In preferred embodiments, the nucleic acid of the first aspect comprises a coding sequence that comprises at least one of the nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the sequences according to SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-13147, 13514, 13515, 13519, 13520, 14124-14177, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23184, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 or a fragment or a fragment or variant of any of these sequences. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column C-F), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

Alternatively, the nucleic acid of the first aspect comprises a coding sequence that comprises at least one of the nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the sequences according SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-13147, 13514, 13515, 13519, 13520, 14124-14177, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23184, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 wherein all Uracils (U) in the respective sequences are substituted by Thymidines (T), or a fragment or a fragment or variant of any of these sequences. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column C-F), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In preferred embodiments, the nucleic acid of the first aspect comprises a coding sequence that comprises at least one of the nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the sequences according to SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or a fragment or a fragment or variant of any of these sequences. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column C-F), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

Alternatively, the nucleic acid of the first aspect comprises a coding sequence that comprises at least one of the nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the sequences according SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 wherein all Uracils (U) in the respective sequences are substituted by Thymidines (T), or a fragment or a fragment or variant of any of these sequences. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column C-F), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In preferred embodiments, the nucleic acid of the first aspect is an artificial nucleic acid, e.g. an artificial DNA or an artificial RNA.

The term “artificial nucleic acid” as used herein is intended to refer to a nucleic acid that does not occur naturally. In other words, an artificial nucleic acid may be understood as a non-natural nucleic acid molecule. Such nucleic acid molecules may be non-natural due to its individual sequence (e.g. G/C content modified coding sequence, UTRs) and/or due to other modifications, e.g. structural modifications of nucleotides. Typically, artificial nucleic acid may be designed and/or generated by genetic engineering to correspond to a desired artificial sequence of nucleotides. In this context, an artificial nucleic acid is a sequence that may not occur naturally, i.e. a sequence that differs from the wild type sequence/the naturally occurring sequence by at least one nucleotide. The term “artificial nucleic acid” is not restricted to mean “one single molecule” but is understood to comprise an ensemble of essentially identical nucleic acid molecules. Accordingly, it may relate to a plurality of essentially identical nucleic acid molecules. The term “artificial nucleic acid” as used herein may relate to an artificial DNA or, preferably, to an artificial RNA.

In preferred embodiments, the nucleic acid, preferably the DNA or RNA of the first aspect is a modified and/or stabilized nucleic acid, preferably a modified and/or stabilized artificial nucleic acid.

According to preferred embodiments, the nucleic acid of the present invention may thus be provided as a “stabilized artificial nucleic acid” or “stabilized coding nucleic acid” that is to say a nucleic acid showing improved resistance to in vivo degradation and/or a nucleic acid showing improved stability in vivo, and/or a nucleic acid showing improved translatability in vivo. In the following, specific suitable modifications/adaptations in this context are described which are suitably to “stabilize” the nucleic acid. Preferably, the nucleic acid of the present invention may be provided as a “stabilized RNA”, “stabilized coding RNA”, “stabilized DNA” or “stabilized coding DNA”.

Such stabilization may be effected by providing a “dried nucleic acid” (e.g. a dried DNA or RNA) and/or a “purified nucleic acid” (e.g. a purified DNA or RNA) as specified herein. Alternatively or in addition to that, such stabilization can be effected, for example, by a modified phosphate backbone of the nucleic acid of the present invention. A backbone modification in connection with the present invention is a modification in which phosphates of the backbone of the nucleotides contained in the nucleic acid are chemically modified. Nucleotides that may be preferably used in this connection contain e.g. a phosphorothioate-modified phosphate backbone, preferably at least one of the phosphate oxygens contained in the phosphate backbone being replaced by a sulfur atom. Stabilized nucleic acids, preferably stabilized RNAs may further include, for example: non-ionic phosphate analogues, such as, for example, alkyl and aryl phosphonates, in which the charged phosphonate oxygen is replaced by an alkyl or aryl group, or phosphodiesters and alkylphosphotriesters, in which the charged oxygen residue is present in alkylated form. Such backbone modifications typically include, without implying any limitation, modifications from the group consisting of methylphosphonates, phosphoramidates and phosphorothioates (e.g. cytidine-5′-O-(1-thiophosphate)).

In the following, suitable modifications are described that are capable of “stabilizing” the nucleic acid of the invention.

In preferred embodiments, the nucleic acid, e.g. the RNA or DNA, comprises at least one codon modified coding sequence.

In preferred embodiments, the at least one coding sequence of the nucleic acid is a codon modified coding sequence, wherein the amino acid sequence encoded by the at least one codon modified coding sequence is preferably not being modified compared to the amino acid sequence encoded by the corresponding wild type or reference coding sequence.

The term “codon modified coding sequence” relates to coding sequences that differ in at least one codon (triplets of nucleotides coding for one amino acid) compared to the corresponding wild type or reference coding sequence. Suitably, a codon modified coding sequence in the context of the invention may show improved resistance to in vivo degradation and/or improved stability in vivo, and/or improved translatability in vivo. Codon modifications in the broadest sense make use of the degeneracy of the genetic code wherein multiple codons may encode the same amino acid and may be used interchangeably (cf. Table 2) to optimize/modify the coding sequence for in vivo applications as outlined above.

The term “reference coding sequence” relates to the coding sequence, which was the origin sequence to be modified and/or optimized.

In preferred embodiments, the at least one coding sequence of the nucleic acid is a codon modified coding sequence, wherein the codon modified coding sequence is selected from C maximized coding sequence, CAI maximized coding sequence, human codon usage adapted coding sequence, G/C content modified coding sequence, and G/C optimized coding sequence, or any combination thereof.

When transfected into mammalian host cells, the nucleic acid comprising a codon modified coding sequence has a stability of between 12-18 hours, or greater than 18 hours, e.g., 24, 36, 48, 60, 72, or greater than 72 hours and are capable of being expressed by the mammalian host cell (e.g. a muscle cell).

When transfected into mammalian host cells, the nucleic acid comprising a codon modified coding sequence is translated into protein, wherein the amount of protein is at least comparable to, or preferably at least 10% more than, or at least 20% more than, or at least 30% more than, or at least 40% more than, or at least 50% more than, or at least 100% more than, or at least 200% or more than the amount of protein obtained by a naturally occurring or wild type or reference coding sequence transfected into mammalian host cells.

In preferred embodiments, the nucleic acid of the invention may be modified, wherein the C content of the at least one coding sequence may be increased, preferably maximized, compared to the C content of the corresponding wild type or reference coding sequence (herein referred to as “C maximized coding sequence”). The amino acid sequence encoded by the C maximized coding sequence of the nucleic acid is preferably not modified compared to the amino acid sequence encoded by the respective wild type or reference coding sequence. The generation of a C maximized nucleic acid sequences may suitably be carried out using a modification method according to WO2015/062738. In this context, the disclosure of WO2015/062738 is included herewith by reference.

In preferred embodiments, the nucleic acid may be modified, wherein the G/C content of the at least one coding sequence may be optimized compared to the G/C content of the corresponding wild type or reference coding sequence (herein referred to as “G/C content optimized coding sequence”). “Optimized” in that context refers to a coding sequence wherein the G/C content is preferably increased to the essentially highest possible G/C content. The amino acid sequence encoded by the G/C content optimized coding sequence of the nucleic acid is preferably not modified as compared to the amino acid sequence encoded by the respective wild type or reference coding sequence. The generation of a G/C content optimized nucleic acid sequence (RNA or DNA) may be carried out using a method according to WO2002/098443. In this context, the disclosure of WO2002/098443 is included in its full scope in the present invention. Throughout the description, including the <223> identifier of the sequence listing, G/C optimized coding sequences are indicated by the abbreviations “opt1” or “gc”.

In preferred embodiments, the nucleic acid may be modified, wherein the codons in the at least one coding sequence may be adapted to human codon usage (herein referred to as “human codon usage adapted coding sequence”). Codons encoding the same amino acid occur at different frequencies in humans. Accordingly, the coding sequence of the nucleic acid is preferably modified such that the frequency of the codons encoding the same amino acid corresponds to the naturally occurring frequency of that codon according to the human codon usage. For example, in the case of the amino acid Ala, the wild type or reference coding sequence is preferably adapted in a way that the codon “GCC” is used with a frequency of 0.40, the codon “GCT” is used with a frequency of 0.28, the codon “GCA” is used with a frequency of 0.22 and the codon “GCG” is used with a frequency of 0.10 etc. (see Table 2). Accordingly, such a procedure (as exemplified for Ala) is applied for each amino acid encoded by the coding sequence of the nucleic acid to obtain sequences adapted to human codon usage. Throughout the description, including the <223> identifier of the sequence listing, human codon usage adapted coding sequences are indicated by the abbreviation “opt3” or “human”.

In embodiments, the nucleic acid of the invention may be modified, wherein the G/C content of the at least one coding sequence may be modified compared to the G/C content of the corresponding wild type or reference coding sequence (herein referred to as “G/C content modified coding sequence”). In this context, the terms “G/C optimization” or “G/C content modification” relate to a nucleic acid that comprises a modified, preferably an increased number of guanosine and/or cytosine nucleotides as compared to the corresponding wild type or reference coding sequence. Such an increased number may be generated by substitution of codons containing adenosine or thymidine nucleotides by codons containing guanosine or cytosine nucleotides. Advantageously, nucleic acid sequences having an increased G/C content are more stable or show a better expression than sequences having an increased A/U. The amino acid sequence encoded by the G/C content modified coding sequence of the nucleic acid is preferably not modified as compared to the amino acid sequence encoded by the respective wild type or reference sequence. Preferably, the G/C content of the coding sequence of the nucleic acid is increased by at least 10%, 20%, 30%, preferably by at least 40% compared to the G/C content of the coding sequence of the corresponding wild type or reference nucleic acid sequence (herein referred to “opt 10” or “gc mod”)

In embodiments, the nucleic acid may be modified, wherein the codon adaptation index (CAI) may be increased or preferably maximised in the at least one coding sequence (herein referred to as “CAI maximized coding sequence”). It is preferred that all codons of the wild type or reference nucleic acid sequence that are relatively rare in e.g. a human are exchanged for a respective codon that is frequent in the e.g. a human, wherein the frequent codon encodes the same amino acid as the relatively rare codon. Suitably, the most frequent codons are used for each amino acid of the encoded protein (see Table 2, most frequent human codons are marked with asterisks). Suitably, the nucleic acid comprises at least one coding sequence, wherein the codon adaptation index (CAI) of the at least one coding sequence is at least 0.5, at least 0.8, at least 0.9 or at least 0.95. Most preferably, the codon adaptation index (CAI) of the at least one coding sequence is 1 (CAI=1). For example, in the case of the amino acid Ala, the wild type or reference coding sequence may be adapted in a way that the most frequent human codon “GCC” is always used for said amino acid. Accordingly, such a procedure (as exemplified for Ala) may be applied for each amino acid encoded by the coding sequence of the nucleic acid to obtain CAI maximized coding sequences.

In particularly preferred embodiments, the at least one coding sequence of the nucleic acid is a codon modified coding sequence, wherein the codon modified coding sequence is selected a G/C optimized coding sequence, a human codon usage adapted coding sequence, or a G/C modified coding sequence

In preferred embodiments, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a codon modified nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence selected from the group consisting of SEQ ID NOs: 136-138, 140-143, 145-175, 11731-11813, 11815, 11817-12050, 12052, 12054-13147, 14142-14177, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23184, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 or a fragment or variant of any of these sequences. Additional information regarding each of these suitable nucleic acid sequences encoding may also be derived from the sequence listing, in particular from the details provided therein under identifier <223>. Suitable coding sequences of the first aspect are provided in Table 1. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column D-F), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

Alternatively, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a codon modified nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the sequences according to SEQ ID NOs: 136-138, 140-143, 145-175, 11731-11813, 11815, 11817-12050, 12052, 12054-13147, 14142-14177, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23184, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 wherein all Uracils (U) in the respective sequences are substituted by Thymidines (T), or a fragment or a fragment or variant of any of these sequences. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column D-F), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In particularly preferred embodiments, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a G/C optimized coding sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence selected from the group consisting of SEQ ID NOs: 136-138, 140, 141, 148, 149, 152, 155, 156, 159, 162, 163, 166, 169, 170, 173, 11731-11813, 11815, 11817-11966, 12271-12472, 12743-12944, 13514, 13515, 14124-14132, 14142-14150, 14160-14168, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23040, 23077-23148, 23189-23260, 23297-23368, 23409-23480, 23517-23588, 23629-23700, 23737-23808, 23849-23920, 23957-24028, 24069-24140, 24177-24248, 24289-24360, 24397-24468, 24509-24580, 24617-24688, 24729-24800, 24837-24908, 24949-25020, 25057-25128, 25169-25240, 25277-25348, 25389-25460, 25497-25568, 25609-25680, 25717-25788, 25829-25900, 25937-26008, 26049-26120, 26157-26228, 26269-26340, 26377-26448, 26489-26560, 26597-26668, 26709-26780, 26817-26888, 26925-26937 or a fragment or variant of any of these sequences. Additional information regarding each of these suitable nucleic acid sequences encoding may also be derived from the sequence listing, in particular from the details provided therein under identifier <223>. Suitable coding sequences of the first aspect are provided in Table 1. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column D), Table 3a and 3b, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In particularly preferred embodiments, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a human codon usage adapted coding sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence selected from the group consisting of SEQ ID NOs: 142, 143, 145, 150, 153, 157, 160, 164, 167, 171, 174, 11967-12033, 12473-12539, 12945-13011 or a fragment or variant of any of these sequences. Additional information regarding each of these suitable nucleic acid sequences encoding may also be derived from the sequence listing, in particular from the details provided therein under identifier <223>. Suitable coding sequences of the first aspect are provided in Table 1. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column E), Table 3a, and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In particularly preferred embodiments, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a G/C modified coding sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence selected from the group consisting of SEQ ID NOs: 146, 147, 151, 154, 158, 161, 165, 168, 172, 175, 12034-12050, 12052, 12054-12203, 12540-12675, 13012-13147, 13519, 13520, 14133-14141, 14151-14159, 14169-14177, 23041-23076, 23149-23184, 23261-23296, 23369-23404, 23481-23516, 23589-23624, 23701-23736, 23809-23844, 23921-23956, 24029-24064, 24141-24176, 24249-24284, 24361-24396, 24469-24504, 24581-24616, 24689-24724, 24801-24836, 24909-24944, 25021-25056, 25129-25164, 25241-25276, 25349-25384, 25461-25496, 25569-25604, 25681-25716, 25789-25824, 25901-25936, 26009-26044, 26121-26156, 26229-26264, 26341-26376, 26449-26484, 26561-26596, 26669-26704, 26781-26816, 26889-26924 or a fragment or variant of any of these sequences. Additional information regarding each of these suitable nucleic acid sequences encoding may also be derived from the sequence listing, in particular from the details provided therein under identifier <223>. Suitable coding sequences of the first aspect are provided in Table 1. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column F), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In even more preferred embodiments, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a G/C modified coding sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence selected from the group consisting of SEQ ID NOs: 136-138, 142, 143, 146, 147, 11731, 11798-11801, 11804, 11805, 11808, 11810-11812, 11923, 11953, 12035, 12049, 22759-22785, 22965-22982, 23077-23094, 23149 or a fragment or variant of any of these sequences. Additional information regarding each of these suitable nucleic acid sequences encoding may also be derived from the sequence listing, in particular from the details provided therein under identifier <223>. Suitable coding sequences of the first aspect are provided in Table 1. Further information regarding said nucleic acid sequences is also provided in Table 1 (see rows 1 to 7, 9, 11-41 of Column F), and under <223> identifier of the ST25 sequence listing of respective sequence SEQ ID NOs.

In a particularly preferred embodiment, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a G/C modified coding sequence encoding a SARS-CoV-2 antigen which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence according to SEQ ID NOs: 137 or a fragment or variant thereof.

In further particularly preferred embodiments, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a G/C modified coding sequence encoding a SARS-CoV-2 antigen which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence according to SEQ ID NOs: 23090, 23091, 23093, 23094 or a fragment or variant thereof.

In further embodiments, the nucleic acid of the first aspect comprises at least one coding sequence comprising or consisting a coding sequence encoding a SARS-CoV-2 antigen which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a codon modified nucleic acid sequence according to SEQ ID NOs: 23113, 23167 or a fragment or variant thereof.

UTRs:

In preferred embodiments, the nucleic acid of the invention comprises a protein-coding region (“coding sequence” or “cds”), and 5′-UTR and/or 3′-UTR. Notably, UTRs may harbor regulatory sequence elements that determine nucleic acid, e.g. RNA turnover, stability, and localization. Moreover, UTRs may harbor sequence elements that enhance translation. In medical application of nucleic acid sequences (including DNA and RNA), translation of the nucleic acid into at least one peptide or protein is of paramount importance to therapeutic efficacy. Certain combinations of 3′-UTRs and/or 5′-UTRs may enhance the expression of operably linked coding sequences encoding peptides or proteins of the invention. Nucleic acid molecules harboring said UTR combinations advantageously enable rapid and transient expression of antigenic peptides or proteins after administration to a subject, preferably after intramuscular administration. Accordingly, the nucleic acid comprising certain combinations of 3′-UTRs and/or 5′-UTRs as provided herein is particularly suitable for administration as a vaccine, in particular, suitable for administration into the muscle, the dermis, or the epidermis of a subject.

Suitably, the nucleic acid of the invention comprises at least one heterologous 5′-UTR and/or at least one heterologous 3′-UTR. Said heterologous 5′-UTRs or 3′-UTRs may be derived from naturally occurring genes or may be synthetically engineered. In preferred embodiments, the nucleic acid, preferably the RNA comprises at least one coding sequence as defined herein operably linked to at least one (heterologous) 3′-UTR and/or at least one (heterologous) 5′-UTR.

In preferred embodiments, the nucleic acid, e.g. the RNA or DNA, comprises at least one heterologous 3′-UTR.

The term “3′-untranslated region” or “3′-UTR” or “3′-UTR element” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a part of a nucleic acid molecule located 3′ (i.e. downstream) of a coding sequence and which is not translated into protein. A 3′-UTR may be part of a nucleic acid, e.g. a DNA or an RNA, located between a coding sequence and an (optional) terminal poly(A) sequence. A 3′-UTR may comprise elements for controlling gene expression, also called regulatory elements. Such regulatory elements may be, e.g., ribosomal binding sites, miRNA binding sites etc.

Preferably, the nucleic acid comprises a 3′-UTR, which may be derivable from a gene that relates to an RNA with enhanced half-life (i.e. that provides a stable RNA).

In some embodiments, a 3′-UTR comprises one or more of a polyadenylation signal, a binding site for proteins that affect a nucleic acid stability of location in a cell, or one or more miRNA or binding sites for miRNAs.

MicroRNAs (or miRNA) are 19-25 nucleotide long noncoding RNAs that bind to the 3′-UTR of nucleic acid molecules and down-regulate gene expression either by reducing nucleic acid molecule stability or by inhibiting translation. E.g., microRNAs are known to regulate RNA, and thereby protein expression, e.g. in liver (miR-122), heart (miR-Id, miR-149), endothelial cells (miR-17-92, miR-126), adipose tissue (let-7, miR-30c), kidney (miR-192, miR-194, miR-204), myeloid cells (miR-142-3p, miR-142-5p, miR-16, miR-21, miR-223, miR-24, miR-27), muscle (miR-133, miR-206, miR-208), and lung epithelial cells (let-7, miR-133, miR-126). The RNA may comprise one or more microRNA target sequences, microRNA sequences, or microRNA seeds. Such sequences may e.g. correspond to any known microRNA such as those taught in US2005/0261218 and US2005/0059005.

Accordingly, miRNA, or binding sites for miRNAs as defined above may be removed from the 3′-UTR or introduced into the 3′-UTR in order to tailor the expression of the nucleic acid, e.g. the RNA to desired cell types or tissues (e.g. muscle cells).

In preferred embodiments, the nucleic acid comprises at least one heterologous 3′-UTR, wherein the at least one heterologous 3′-UTR comprises a nucleic acid sequence derived from a 3′-UTR of a gene selected from PSMB3, ALB7, alpha-globin (referred to as “muag”), CASP1, COX6B1, GNAS, NDUFA1 and RPS9, or from a homolog, a fragment or variant of any one of these genes, preferably according to nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 253-268, 22902-22905, 22892-22895 or a fragment or a variant of any of these. Particularly preferred nucleic acid sequences in that context can be derived from published PCT application WO2019/077001A1, in particular, claim 9 of WO2019/077001A1. The corresponding 3′-UTR sequences of claim 9 of WO2019/077001A1 are herewith incorporated by reference (e.g., SEQ ID NOs: 23-34 of WO2019/077001A1, or fragments or variants thereof).

In particularly preferred embodiments, the nucleic acid comprises a 3′-UTR derived from an alpha-globin gene. Said 3′-UTR derived from a alpha-globin gene (“muag”) may comprise or consist of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 267, 268, 22896-22901, 22906-22911 or a fragment or a variant thereof.

In further embodiments, the nucleic acid comprises a 3′-UTR derived from a RPS9 gene. Said 3′-UTR derived from a RPS9 gene may comprise or consist of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 263 or 264, 22894, 22895, 22904, 22905 or a fragment or a variant thereof.

In preferred embodiments, the nucleic acid comprises a 3′-UTR derived from a PSMB3 gene. Said 3′-UTR derived from a PSMB3 gene may comprise or consist of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 253 or 254, 22892, 22893, 22902, 22903 or a fragment or a variant thereof.

In other embodiments, the nucleic acid comprises a 3′-UTR which comprises or consists of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 22876-22891 or a fragment or a variant thereof.

In other embodiments, the nucleic acid may comprise a 3′-UTR as described in WO2016/107877, the disclosure of WO2016/107877 relating to 3′-UTR sequences herewith incorporated by reference. Suitable 3′-UTRs are SEQ ID NOs: 1-24 and SEQ ID NOs: 49-318 of WO2016/107877, or fragments or variants of these sequences. In other embodiments, the nucleic acid comprises a 3′-UTR as described in WO2017/036580, the disclosure of WO2017/036580 relating to 3′-UTR sequences herewith incorporated by reference. Suitable 3′-UTRs are SEQ ID NOs: 152-204 of WO2017/036580, or fragments or variants of these sequences. In other embodiments, the nucleic acid comprises a 3′-UTR as described in WO2016/022914, the disclosure of WO2016/022914 relating to 3′-UTR sequences herewith incorporated by reference. Particularly preferred 3′-UTRs are nucleic acid sequences according to SEQ ID NOs: 20-36 of WO2016/022914, or fragments or variants of these sequences.

In preferred embodiments, the nucleic acid, e.g. the RNA or DNA, comprises at least one heterologous 5′-UTR.

The terms “5′-untranslated region” or “5′-UTR” or “5′-UTR element” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a part of a nucleic acid molecule located 5′ (i.e. “upstream”) of a coding sequence and which is not translated into protein. A 5′-UTR may be part of a nucleic acid located 5′ of the coding sequence. Typically, a 5′-UTR starts with the transcriptional start site and ends before the start codon of the coding sequence. A 5′-UTR may comprise elements for controlling gene expression, also called regulatory elements. Such regulatory elements may be, e.g., ribosomal binding sites, miRNA binding sites etc. The 5′-UTR may be post-transcriptionally modified, e.g. by enzymatic or post-transcriptional addition of a 5′-cap structure (e.g. for mRNA as defined below).

Preferably, the nucleic acid comprises a 5′-UTR, which may be derivable from a gene that relates to an RNA with enhanced half-life (i.e. that provides a stable RNA).

In some embodiments, a 5′-UTR comprises one or more of a binding site for proteins that affect an RNA stability or RNA location in a cell, or one or more miRNA or binding sites for miRNAs (as defined above).

Accordingly, miRNA or binding sites for miRNAs as defined above may be removed from the 5′-UTR or introduced into the 5′-UTR in order to tailor the expression of the nucleic acid to desired cell types or tissues (e.g. muscle cells).

In preferred embodiments, the nucleic acid comprises at least one heterologous 5′-UTR, wherein the at least one heterologous 5′-UTR comprises a nucleic acid sequence derived from a 5′-UTR of gene selected from HSD17B4, RPL32, ASAH1, ATP5A1, MP68, NDUFA4, NOSIP, RPL31, SLC7A3, TUBB4B, and UBQLN2, or from a homolog, a fragment or variant of any one of these genes according to nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 231-252, 22870-22875 or a fragment or a variant of any of these. Particularly preferred nucleic acid sequences in that context can be selected from published PCT application WO2019/077001A1, in particular, claim 9 of WO2019/077001A1. The corresponding 5′-UTR sequences of claim 9 of WO2019/077001A1 are herewith incorporated by reference (e.g., SEQ ID NOs: 1-20 of WO2019/077001A1, or fragments or variants thereof).

In preferred embodiments, the nucleic acid comprises a 5′-UTR derived from a RPL31 gene, wherein said 5′-UTR derived from a RPL31 gene comprises or consists of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 243, 244, 22872, 22873 or a fragment or a variant thereof.

In other embodiments, the nucleic acid comprises a 5′-UTR derived from a SLC7A3 gene, wherein said 5′-UTR derived from a SLC7A3 gene comprises or consists of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 245, 246, 22874, 22875 or a fragment or a variant thereof.

In particularly preferred embodiments, the nucleic acid comprises a 5′-UTR derived from a HSD17B4 gene, wherein said 5′-UTR derived from a HSD17B4 gene comprises or consists of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 231, 232, 22870, 22871 or a fragment or a variant thereof.

In other embodiments, the nucleic acid comprises a 5′-UTR which comprises or consists of a nucleic acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 22848-22869 or a fragment or a variant thereof.

In other embodiments, the nucleic acid comprises a 5′-UTR as described in WO2013/143700, the disclosure of WO2013/143700 relating to 5′-UTR sequences herewith incorporated by reference. Particularly preferred 5′-UTRs are nucleic acid sequences derived from SEQ ID NOs: 1-1363, SEQ ID NO: 1395, SEQ ID NO: 1421 and SEQ ID NO: 1422 of WO2013/143700, or fragments or variants of these sequences. In other embodiments, the nucleic acid comprises a 5′-UTR as described in WO2016/107877, the disclosure of WO2016/107877 relating to 5′-UTR sequences herewith incorporated by reference. Particularly preferred 5′-UTRs are nucleic acid sequences according to SEQ ID NOs: 25-30 and SEQ ID NOs: 319-382 of WO2016/107877, or fragments or variants of these sequences. In other embodiments, the nucleic acid comprises a 5′-UTR as described in WO2017/036580, the disclosure of WO2017/036580 relating to 5′-UTR sequences herewith incorporated by reference. Particularly preferred 5′-UTRs are nucleic acid sequences according to SEQ ID NOs: 1-151 of WO2017/036580, or fragments or variants of these sequences. In other embodiments, the nucleic acid comprises a 5′-UTR as described in WO2016/022914, the disclosure of WO2016/022914 relating to 5′-UTR sequences herewith incorporated by reference. Particularly preferred 5′-UTRs are nucleic acid sequences according to SEQ ID NOs: 3-19 of WO2016/022914, or fragments or variants of these sequences.

Suitably, in preferred embodiments, the nucleic acid comprises at least one coding sequence as specified herein encoding at least one antigenic protein as defined herein, preferably derived from SARS-CoV-2 (nCoV-2019) coronavirus, operably linked to a 3′-UTR and/or a 5′-UTR selected from the following 5′UTR/3′UTR combinations (“also referred to UTR designs”):

a-1 (HSD17B4/PSMB3), a-2 (NDUFA4/PSMB3), a-3 (SLC7A3/PSMB3), a-4 (NOSIP/PSMB3), a-5 (MP68/PSMB3), b-1 (UBQLN2/RPS9), b-2 (ASAH1/RPS9), b-3 (HSD17B4/RPS9), b-4 (HSD17B4/CASP1), b-5 (NOSIP/COX6B1), c-1 (NDUFA4/RPS9), c-2 (NOSIP/NDUFA1), c-3 (NDUFA4/COX6B1), c-4 (NDUFA4/NDUFA1), c-5 (ATP5A1/PSMB3), d-1 (Rpl31/PSMB3), d-2 (ATP5A1/CASP1), d-3 (SLC7A3/GNAS), d-4 (HSD17B4/NDUFA1), d-5 (Slc7a3/Ndufa1), e-1 (TUBB4B/RPS9), e-2 (RPL31/RPS9), e-3 (MP68/RPS9), e-4 (NOSIP/RPS9), e-5 (ATP5A1/RPS9), e-6 (ATP5A1/COX6B1), f-1 (ATP5A1/GNAS), f-2 (ATP5A1/NDUFA1), f-3 (HSD17B4/COX6B1), f-4 (HSD17B4/GNAS), f-5 (MP68/COX6B1), g-1 (MP68/NDUFA1), g-2 (NDUFA4/CASP1), g-3 (NDUFA4/GNAS), g-4 (NOSIP/CASP1), g-5 (RPL31/CASP1), h-1 (RPL31/COX6B1), h-2 (RPL31/GNAS), h-3 (RPL31/NDUFA1), h-4 (Slc7a3/CASP1), h-5 (SLC7A3/COX6B1), i-1 (SLC7A3/RPS9), i-2 (RPL32/ALB7), i-2 (RPL32/ALB7), or i-3 (alpha-globin gene).

In particularly preferred embodiments, the nucleic acid comprises at least one coding sequence as specified herein encoding at least one antigenic protein as defined herein, preferably derived from SARS-CoV-2 (nCoV-2019) coronavirus, wherein said coding sequence is operably linked to a HSD17B4 5′-UTR and a PSMB3 3′-UTR (HSD17B4/PSMB3 (UTR design a-1)).

It has been shown by the inventors that this embodiment is particularly beneficial for induction an immune response against SARS-CoV-2. In this context, it could be shown that already one vaccination was sufficient to result in virus-neutralizing antibody titers.

In further preferred embodiments, the nucleic acid comprises at least one coding sequence as specified herein encoding at least one antigenic protein as defined herein, preferably derived from SARS-CoV-2 (nCoV-2019) coronavirus, wherein said coding sequence is operably linked to a SLC7A3 5′-UTR and a PSMB3 3′-UTR (SLC7A3/PSMB3 (UTR design a-3)).

In further preferred embodiments, the nucleic acid comprises at least one coding sequence as specified herein encoding at least one antigenic protein as defined herein, preferably derived from SARS-CoV-2 (nCoV-2019) coronavirus, wherein said coding sequence is operably linked to a RPL31 5′-UTR and a RPS9 3′-UTR (RPL31/RPS9 (UTR design e-2)).

In particularly preferred embodiments of the nucleic acid comprises at least one coding sequence as specified herein encoding at least one antigenic protein as defined herein, preferably derived from SARS-CoV-2 (nCoV-2019) coronavirus, wherein said coding sequence is operably linked to an alpha-globin (“muag”) 3′-UTR (−/muag)(UTR design i-3)).

In some embodiments, the nucleic acid, e.g. the DNA or RNA may be monocistronic, bicistronic, or multicistronic.

The term “monocistronic” will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a nucleic acid that comprises only one coding sequence. The terms “bicistronic”, or “multicistronic” as used herein will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a nucleic acid that may comprise two (bicistronic) or more (multicistronic) coding sequences.

In preferred embodiments, the nucleic acid of the first aspect is monocistronic.

In other embodiments, the nucleic acid is monocistronic and the coding sequence of said nucleic acid encodes at least two different antigenic peptides or proteins derived from a SARS-CoV-2 coronavirus. Accordingly, said coding sequence may encode at least two, three, four, five, six, seven, eight and more antigenic peptides or proteins derived from a SARS-CoV-2 coronavirus, linked with or without an amino acid linker sequence, wherein said linker sequence can comprise rigid linkers, flexible linkers, cleavable linkers, or a combination thereof. Such constructs are herein referred to as “multi-antigen-constructs”.

In further embodiments, the nucleic acid may be bicistronic or multicistronic and comprises at least two coding sequences, wherein the at least two coding sequences encode two or more different antigenic peptides or proteins derived from a SARS-CoV-2 coronavirus. Accordingly, the coding sequences in a bicistronic or multicistronic nucleic acid suitably encodes distinct antigenic proteins or peptides as defined herein or immunogenic fragments or immunogenic variants thereof. Preferably, the coding sequences in said bicistronic or multicistronic constructs may be separated by at least one IRES (internal ribosomal entry site) sequence. Thus, the term “encoding two or more antigenic peptides or proteins” may mean, without being limited thereto, that the bicistronic or multicistronic nucleic acid encodes e.g. at least two, three, four, five, six or more (preferably different) antigenic peptides or proteins of different SARS-CoV-2 coronavirus isolates. Alternatively, the bicistronic or multicistronic nucleic acid may encode e.g. at least two, three, four, five, six or more (preferably different) antigenic peptides or proteins derived from the same SARS-CoV-2 coronavirus. In that context, suitable IRES sequences may be selected from the list of nucleic acid sequences according to SEQ ID NOs: 1566-1662 of the patent application WO2017/081082, or fragments or variants of these sequences. In this context, the disclosure of WO2017/081082 relating to IRES sequences is herewith incorporated by reference.

It has to be understood that, in the context of the invention, certain combinations of coding sequences may be generated by any combination of monocistronic, bicistronic and multicistronic DNA and/or RNA constructs and/or multi-antigen-constructs to obtain a nucleic acid set encoding multiple antigenic peptides or proteins as defined herein.

In preferred embodiments, the A/U (A/T) content in the environment of the ribosome binding site of the nucleic acid may be increased compared to the A/U (NT) content in the environment of the ribosome binding site of its respective wild type or reference nucleic acid. This modification (an increased A/U (A/T) content around the ribosome binding site) increases the efficiency of ribosome binding to the nucleic acid, e.g. to an RNA. An effective binding of the ribosomes to the ribosome binding site in turn has the effect of an efficient translation the nucleic acid.

Accordingly, in a particularly preferred embodiment, the nucleic acid comprises a ribosome binding site, also referred to as “Kozak sequence” identical to or at least 80%, 85%, 90%, 95% identical to any one of the sequences SEQ ID NOs: 180, 181, 22845-22847, or fragments or variants thereof.

In preferred embodiments, the nucleic acid of the invention comprises at least one poly(N) sequence, e.g. at least one poly(A) sequence, at least one poly(U) sequence, at least one poly(C) sequence, or combinations thereof.

In preferred embodiments, the nucleic acid of the invention, preferably the RNA comprises at least one poly(A) sequence.

The terms “poly(A) sequence”, “poly(A) tail” or “3′-poly(A) tail” as used herein will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to be a sequence of adenosine nucleotides, typically located at the 3′-end of a linear RNA (or in a circular RNA), of up to about 1000 adenosine nucleotides. Preferably, said poly(A) sequence is essentially homopolymeric, e.g. a poly(A) sequence of e.g. 100 adenosine nucleotides has essentially the length of 100 nucleotides. In other embodiments, the poly(A) sequence may be interrupted by at least one nucleotide different from an adenosine nucleotide, e.g. a poly(A) sequence of e.g. 100 adenosine nucleotides may have a length of more than 100 nucleotides (comprising 100 adenosine nucleotides and in addition said at least one nucleotide—or a stretch of nucleotides—different from an adenosine nucleotide). It has to be understood that “poly(A) sequence” as defined herein typically relates to RNA—however in the context of the invention, the term likewise relates to corresponding sequences in a DNA molecule (e.g. a “poly(T) sequence”).

The poly(A) sequence may comprise about 10 to about 500 adenosine nucleotides, about 10 to about 200 adenosine nucleotides, about 40 to about 200 adenosine nucleotides, or about 40 to about 150 adenosine nucleotides. Suitably, the length of the poly(A) sequence may be at least about or even more than about 10, 50, 64, 75, 100, 200, 300, 400, or 500 adenosine nucleotides.

In preferred embodiments, the nucleic acid comprises at least one poly(A) sequence comprising about 30 to about 200 adenosine nucleotides. In particularly preferred embodiments, the poly(A) sequence comprises about 64 adenosine nucleotides (A64). In other particularly preferred embodiments, the poly(A) sequence comprises about 100 adenosine nucleotides (A100). In other embodiments, the poly(A) sequence comprises about 150 adenosine nucleotides.

In further embodiments, the nucleic acid comprises at least one poly(A) sequence comprising about 100 adenosine nucleotides, wherein the poly(A) sequence is interrupted by non-adenosine nucleotides, preferably by 10 non-adenosine nucleotides (A30-N10-A70).

The poly(A) sequence as defined herein may be located directly at the 3′ terminus of the nucleic acid, preferably directly at the 3′ terminus of an RNA.

In preferred embodiments, the 3′-terminal nucleotide (that is the last 3′-terminal nucleotide in the polynucleotide chain) is the 3′-terminal A nucleotide of the at least one poly(A) sequence. The term “directly located at the 3′ terminus” has to be understood as being located exactly at the 3′ terminus—in other words, the 3′ terminus of the nucleic acid consists of a poly(A) sequence terminating with an A nucleotide.

It has been shown by the inventors that this embodiment is particularly beneficial for induction an immune response against SARS-CoV-2. In this context, it could be shown that already one vaccination was sufficient to result in virus-neutralizing antibody titers.

In a particularly preferred embodiment the nucleic acid sequence, preferably the RNA comprises a poly(A) sequence of at least 70 adenosine nucleotides, wherein the 3′-terminal nucleotide is an adenosine nucleotide. In this context it has been shown that ending on an adenosine nucleotide decreases the induction of IFNalpha by the RNA vaccine. This is particularly important as the induction of IFNalpha is thought to be the main factor for induction of fever in vaccinated subjects, which of course has to be avoided.

In embodiments where the nucleic acid is an RNA, the poly(A) sequence of the nucleic acid is preferably obtained from a DNA template during RNA in vitro transcription. In other embodiments, the poly(A) sequence is obtained in vitro by common methods of chemical synthesis without being necessarily transcribed from a DNA template. In other embodiments, poly(A) sequences are generated by enzymatic polyadenylation of the RNA (after RNA in vitro transcription) using commercially available polyadenylation kits and corresponding protocols known in the art, or alternatively, by using immobilized poly(A)polymerases e.g. using a methods and means as described in WO2016/174271.

The nucleic acid may comprise a poly(A) sequence obtained by enzymatic polyadenylation, wherein the majority of nucleic acid molecules comprise about 100 (+/−20) to about 500 (+/−50), preferably about 250 (+/−20) adenosine nucleotides.

In other embodiments, the nucleic acid may comprise a poly(A) sequence derived from a template DNA and may additionally comprise at least one additional poly(A) sequence generated by enzymatic polyadenylation, e.g. as described in WO2016/091391.

In further embodiments, the nucleic acid comprises at least one polyadenylation signal.

In other embodiments, the nucleic acid may comprise at least one poly(C) sequence.

The term “poly(C) sequence” as used herein is intended to be a sequence of cytosine nucleotides of up to about 200 cytosine nucleotides. In preferred embodiments, the poly(C) sequence comprises about 10 to about 200 cytosine nucleotides, about 10 to about 100 cytosine nucleotides, about 20 to about 70 cytosine nucleotides, about 20 to about 60 cytosine nucleotides, or about 10 to about 40 cytosine nucleotides. In a particularly preferred embodiment, the poly(C) sequence comprises about 30 cytosine nucleotides.

In preferred embodiments, the nucleic acid of the invention comprises at least one histone stem-loop (hSL).

The term “histone stem-loop” (abbreviated as “hSL” in e.g. the sequence listing) is intended to refer to nucleic acid sequences that form a stem-loop secondary structure predominantly found in histone mRNAs.

Histone stem-loop sequences/structures may suitably be selected from histone stem-loop sequences as disclosed in WO2012/019780, the disclosure relating to histone stem-loop sequences/histone stem-loop structures incorporated herewith by reference. A histone stem-loop sequence that may be used within the present invention may preferably be derived from formulae (I) or (II) of WO2012/019780. According to a further preferred embodiment, the nucleic acid may comprise at least one histone stem-loop sequence derived from at least one of the specific formulae (Ia) or (IIa) of the patent application WO2012/019780.

In preferred embodiments, the nucleic acid of the invention comprises at least one histone stem-loop, wherein said histone stem-loop (hSL) comprises or consists a nucleic acid sequence identical or at least 70%, 80%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 178 or 179, or fragments or variants thereof.

In other embodiments, the RNA of the first aspect does not comprise a histone stem-loop as defined herein.

In some embodiments, in particular in embodiments that relate to RNA, the nucleic acid comprises a 3′-terminal sequence element. Said 3′-terminal sequence element comprises a poly(A) sequence and optionally a histone-stem-loop sequence. Accordingly, the nucleic acid of the invention comprises at least one 3′-terminal sequence element comprising or consisting of a nucleic acid sequence being identical or at least 70%, 80%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 182-230, 22912, 22913 or a fragment or variant thereof.

In preferred embodiments, in particular in embodiments that relate to RNA, the nucleic acid comprises a 3′-terminal sequence element. Said 3′-terminal sequence element comprises a poly(A) sequence and optionally a histone-stem-loop sequence. Accordingly, the nucleic acid of the invention comprises at least one 3′-terminal sequence element comprising or consisting of a nucleic acid sequence being identical or at least 70%, 80%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOs: 182, 187, 189, 192, 199, 207, or a fragment or variant thereof.

In various embodiments, in particular in embodiments that relate to RNA, the nucleic acid may comprise a 5′-terminal sequence element according to SEQ ID NOs: 176 or 177, 22840-22844, or a fragment or variant thereof. Such a 5′-terminal sequence element comprises e.g. a binding site for T7 RNA polymerase. Further, the first nucleotide of said 5′-terminal start sequence may preferably comprise a 2′O methylation, e.g. 2′O methylated guanosine or a 2′O methylated adenosine.

Preferably, the nucleic acid of the first aspect, e.g. the RNA or DNA, typically comprises about 50 to about 20000 nucleotides, or about 500 to about 10000 nucleotides, or about 1000 to about 10000 nucleotides, or preferably about 1000 to about 5000 nucleotides, or even more preferably about 2000 to about 5000 nucleotides.

In some embodiments, the nucleic acid is a DNA or an RNA.

In various embodiments, the DNA is a plasmid DNA or a linear coding DNA construct, wherein the DNA comprises or consists of the nucleic acid elements as defined herein (e.g. including coding sequences, UTRs, poly(A/T), polyadenylation signal, a promoter).

In preferred embodiments, the nucleic acid is a DNA expression vector. Such a DNA expression vector may be selected from the group consisting of a bacterial plasmid, an adenovirus, a poxvirus, a parapoxivirus (orf virus), a vaccinia virus, a fowlpox virus, a herpes virus, an adeno-associated virus (AAV), an alphavirus, a lentivirus, a lambda phage, a lymphocytic choriomeningitis virus and a Listeria sp, Salmonella sp.

Suitably, the DNA may also comprise a promoter that is operably linked to the SARS-CoV-2 antigen coding sequence. The promoter operably linked to the antigen coding sequence can be e.g. a promoter from simian virus 40 (SV40), a mouse mammary tumor virus (MMTV) promoter, a human immunodeficiency virus (HIV) promoter such as the bovine immunodeficiency virus (BIV) long terminal repeat (LTR) promoter, a Moloney virus promoter, an avian leukosis virus (ALV) promoter, a cytomegalovirus (CMV) promoter such as the CMV immediate early promoter, Epstein Barr virus (EBV) promoter, or a Rous sarcoma virus (RSV) promoter. The promoter can also be a promoter from a human gene such as human actin, human myosin, human hemoglobin, human muscle creatine, or human metalothionein. The promoter can also be a tissue specific promoter, such as a muscle or skin specific promoter, natural or synthetic. Examples of such promoters are described in US patent application publication no. US20040175727. In preferred embodiments, the vector can be pVAX, pcDNA3.0, or provax, or any other expression vector capable of expressing DNA encoding the coronavirus antigen and enabling a cell to translate the sequence to an antigen that is recognized by the immune system.

Further suitable plasmid DNA may be generated to allow efficient production of the encoded SARS-CoV-2 antigen in cell lines, e.g. in insect cell lines, for example using vectors as described in WO2009150222A2 and as defined in PCT claims 1 to 33, the disclosure relating to claims 1 to 33 of WO2009150222A2 herewith incorporated by reference.

In other embodiments, the nucleic acid of the first aspect is an adenovirus based vector. Such an adenovirus based vector may comprise at least one coding sequence encoding at least one SARS-CoV-2 antigenic peptide or protein as defined herein.

In the context of the invention, any suitable adenovirus based vector may be used such as those described in WO2005/071093 or WO2006/048215. Suitably, the adenovirus based vector used is a simian adenovirus, thereby avoiding dampening of the immune response after vaccination by pre-existing antibodies to common human entities such as AdHu5. Suitable simian adenovirus vectors include AdCh63 (patent number WO/2005/071093) or AdCh68 (Cohen et al J. Gen Virol 2002 83:151) but others may also be used. Suitably the adenovirus vector will have the E1 region deleted, rendering it replication-deficient in human cells. Other regions of the adenovirus such as E3 and E4 may also be deleted.

In additional embodiments, the nucleic acid of the first aspect is an orf virus based vector. Such an adenovirus based vector may comprise at least one coding sequence encoding at least one SARS-CoV-2 antigenic peptide or protein as defined herein.

In particularly preferred embodiments of the invention, the nucleic acid of the invention is an RNA.

Preferably, the RNA typically comprises about 50 to about 20000 nucleotides, or about 500 to about 10000 nucleotides, or about 1000 to about 10000 nucleotides, or preferably about 1000 to about 5000 nucleotides, or even more preferably about 2000 to about 5000 nucleotides.

According to preferred embodiments, the nucleic acid is an RNA, preferably a coding RNA.

In preferred embodiments, the coding RNA may be selected from an mRNA, a (coding) self-replicating RNA, a (coding) circular RNA, a (coding) viral RNA, or a (coding) replicon RNA.

In other embodiments, the coding RNA is a circular RNA. As used herein, “circular RNA” or “circRNAs” have to be understood as a circular polynucleotide constructs that encode at least one antigenic peptide or protein as defined herein. Preferably, such a circRNA is a single stranded RNA molecule. In preferred embodiments, said circRNA comprises at least one coding sequence encoding at least one antigenic protein from a SARS-CoV-2 coronavirus, or an immunogenic fragment or an immunogenic variant thereof.

In further embodiments, the coding RNA is a replicon RNA. The term “replicon RNA” will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to be an optimized self-replicating RNA. Such constructs may include replicase elements derived from e.g. alphaviruses (e.g. SFV, SIN, VEE, or RRV) and the substitution of the structural virus proteins with the nucleic acid of interest (that is, the coding sequence encoding an antigenic peptide or protein of a SARS-CoV-2 coronavirus). Alternatively, the replicase may be provided on an independent coding RNA construct or a coding DNA construct. Downstream of the replicase may be a sub-genomic promoter that controls replication of the replicon RNA.

In particularly preferred embodiments, the at least one nucleic acid is not a replicon RNA or a self-replicating RNA. In particularly preferred embodiments, the nucleic acid of the invention is an mRNA.

Preferably, the mRNA does not comprise a replicase element (e.g. a nucleic acid encoding a replicase).

The terms “RNA” and “mRNA” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to be a ribonucleic acid molecule, i.e. a polymer consisting of nucleotides. These nucleotides are usually adenosine-monophosphate, uridine-monophosphate, guanosine-monophosphate and cytidine-monophosphate monomers which are connected to each other along a so-called backbone. The backbone is formed by phosphodiester bonds between the sugar, i.e. ribose, of a first and a phosphate moiety of a second, adjacent monomer. The specific succession of the monomers is called the RNA-sequence. The mRNA (messenger RNA) provides the nucleotide coding sequence that may be translated into an amino-acid sequence of a particular peptide or protein.

In the context of the invention, the coding RNA, preferably the mRNA, may provide at least one coding sequence encoding an antigenic protein from a SARS-CoV-2 that is translated into a (functional) antigen after administration (e.g. after administration to a subject, e.g. a human subject).

Accordingly, the coding RNA, preferably the mRNA, is suitable for a vaccine, preferably a SARS-CoV-2 vaccine.

Suitably, the coding RNA may be modified by the addition of a 5′-cap structure, which preferably stabilizes the coding RNA and/or enhances expression of the encoded antigen and/or reduces the stimulation of the innate immune system (after administration to a subject). A 5′-cap structure is of particular importance in embodiments where the nucleic acid is an RNA, in particular a linear coding RNA, e.g. a linear mRNA or a linear coding replicon RNA.

Accordingly, in preferred embodiments, the RNA, in particular the coding RNA comprises a 5′-cap structure, preferably cap0, cap1, cap2, a modified cap0, or a modified cap1 structure.

The term “5′-cap structure” as used herein will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a 5′ modified nucleotide, particularly a guanine nucleotide, positioned at the 5′-end of an RNA, e.g. an mRNA. Preferably, the 5′-cap structure is connected via a 5′-5′-triphosphate linkage to the RNA.

5′-cap structures which may be suitable in the context of the present invention are cap0 (methylation of the first nucleobase, e.g. m7GpppN), cap1 (additional methylation of the ribose of the adjacent nucleotide of m7GpppN), cap2 (additional methylation of the ribose of the 2nd nucleotide downstream of the m7GpppN), cap3 (additional methylation of the ribose of the 3rd nucleotide downstream of the m7GpppN), cap4 (additional methylation of the ribose of the 4th nucleotide downstream of the m7GpppN), ARCA (anti-reverse cap analogue), modified ARCA (e.g. phosphothioate modified ARCA), inosine, N1-methyl-guanosine, 2′-fluoro-guanosine, 7-deaza-guanosine, 8-oxo-guanosine, 2-amino-guanosine, LNA-guanosine, and 2-azido-guanosine.

A 5′-cap (cap0 or cap1) structure may be formed in chemical RNA synthesis or in RNA in vitro transcription (co-transcriptional capping) using cap analogues.

The term “cap analogue” as used herein will be recognized and understood by the person of ordinary skill in the art, and is e.g. intended to refer to a non-polymerizable di-nucleotide or tri-nucleotide that has cap functionality in that it facilitates translation or localization, and/or prevents degradation of a nucleic acid molecule, particularly of an RNA molecule, when incorporated at the 5′-end of the nucleic acid molecule. Non-polymerizable means that the cap analogue will be incorporated only at the 5′-terminus because it does not have a 5′ triphosphate and therefore cannot be extended in the 3′-direction by a template-dependent polymerase, particularly, by template-dependent RNA polymerase. Examples of cap analogues include, but are not limited to, a chemical structure selected from the group consisting of m7GpppG, m7GpppA, m7GpppC; unmethylated cap analogues (e.g. GpppG); dimethylated cap analogue (e.g. m2,7GpppG), trimethylated cap analogue (e.g. m2,2,7GpppG), dimethylated symmetrical cap analogues (e.g. m7Gpppm7G), or anti reverse cap analogues (e.g. ARCA; m7,2′OmeGpppG, m7,2′dGpppG, m7,3′OmeGpppG, m7,3′dGpppG and their tetraphosphate derivatives). Further cap analogues have been described previously (WO2008/016473, WO2008/157688, WO2009/149253, WO2011/015347, and WO2013/059475). Further suitable cap analogues in that context are described in WO2017/066793, WO2017/066781, WO2017/066791, WO2017/066789, WO2017/053297, WO2017/066782, WO2018/075827 and WO2017/066797 wherein the disclosures referring to cap analogues are incorporated herewith by reference.

In some embodiments, a modified cap1 structure is generated using tri-nucleotide cap analogue as disclosed in WO2017/053297, WO2017/066793, WO2017/066781, WO2017/066791, WO2017/066789, WO2017/066782, WO2018/075827 and WO2017/066797. In particular, any cap structures derivable from the structure disclosed in claim 1-5 of WO2017/053297 may be suitably used to co-transcriptionally generate a modified cap1 structure. Further, any cap structures derivable from the structure defined in claim 1 or claim 21 of WO2018/075827 may be suitably used to co-transcriptionally generate a modified cap1 structure.

In preferred embodiments, the (coding) RNA, in particular the mRNA comprises a cap1 structure.

In preferred embodiments, the 5′-cap structure may suitably be added co-transcriptionally using tri-nucleotide cap analogue as defined herein in an RNA in vitro transcription reaction as defined herein.

In preferred embodiments, the cap1 structure of the coding RNA of the invention is formed using co-transcriptional capping using tri-nucleotide cap analogues m7G(5′)ppp(5′)(2′OMeA)pG or m7G(5′)ppp(5′)(2′OMeG)pG. A preferred cap1 analogues in that context is m7G(5′)ppp(5′)(2′OMeA)pG.

In other preferred embodiments, the cap1 structure of the RNA of the invention is formed using co-transcriptional capping using tri-nucleotide cap analogue 3′OMe-m7G(5′)ppp(5′)(2′OMeA)pG.

In other embodiments, a cap0 structure of the RNA of the invention is formed using co-transcriptional capping using cap analogue 3′OMe-m7G(5′)ppp(5′)G.

In other embodiments, the 5′-cap structure is formed via enzymatic capping using capping enzymes (e.g. vaccinia virus capping enzymes and/or cap-dependent 2′-O methyltransferases) to generate cap0 or cap1 or cap2 structures.

The 5′-cap structure (cap0 or cap1) may be added using immobilized capping enzymes and/or cap-dependent 2′-O methyltransferases using methods and means disclosed in WO2016/193226.

In preferred embodiments, about 70%, 75%, 80%, 85%, 90%, 95% of the RNA (species) comprises a cap1 structure as determined using a capping assay. In preferred embodiments, less than about 20%, 15%, 10%, 5%, 4%, 3%, 2%, 1% of the RNA (species) does not comprises a cap1 structure as determined using a capping assay. In other preferred embodiments, about 70%, 75%, 80%, 85%, 90%, 95% of the RNA (species) comprises a cap0 structure as determined using a capping assay. In preferred embodiments, less than about 20%, 15%, 10%, 5%, 4%, 3%, 2%, 1% of the RNA (species) does not comprises a cap0 structure as determined using a capping assay.

The term “RNA species” is not restricted to mean “one single molecule” but is understood to comprise an ensemble of essentially identical RNA molecules. Accordingly, it may relate to a plurality of essentially identical (coding) RNA molecules.

For determining the presence/absence of a cap0 or a cap1 structure, a capping assays as described in published PCT application WO2015/101416, in particular, as described in claims 27 to 46 of published PCT application WO2015/101416 can be used. Other capping assays that may be used to determine the presence/absence of a cap0 or a cap1 structure of an RNA are described in PCT/EP2018/08667, or published PCT applications WO2014/152673 and WO2014/152659.

In preferred embodiments, the RNA comprises an m7G(5′)ppp(5′)(2′OMeA) cap structure. In such embodiments, the coding RNA comprises a 5′-terminal m7G cap, and an additional methylation of the ribose of the adjacent nucleotide of m7GpppN, in that case, a 2′O methylated Adenosine. Preferably, about 70%, 75%, 80%, 85%, 90%, 95% of the RNA (species) comprises such a cap1 structure as determined using a capping assay.

In other preferred embodiments, the RNA comprises an m7G(5′)ppp(5′)(2′OMeG) cap structure. In such embodiments, the coding RNA comprises a 5′-terminal m7G cap, and an additional methylation of the ribose of the adjacent nucleotide, in that case, a 2′O methylated guanosine. Preferably, about 70%, 75%, 80%, 85%, 90%, 95% of the coding RNA (species) comprises such a cap1 structure as determined using a capping assay.

Accordingly, the first nucleotide of said RNA or mRNA sequence, that is, the nucleotide downstream of the m7G(5′)ppp structure, may be a 2′O methylated guanosine or a 2′O methylated adenosine.

According to some embodiments, the RNA is a modified RNA, wherein the modification refers to chemical modifications comprising backbone modifications as well as sugar modifications or base modifications.

A modified RNA may comprise nucleotide analogues/modifications, e.g. backbone modifications, sugar modifications or base modifications. A backbone modification in the context of the invention is a modification, in which phosphates of the backbone of the nucleotides of the RNA are chemically modified. A sugar modification in the context of the invention is a chemical modification of the sugar of the nucleotides of the RNA. Furthermore, a base modification in the context of the invention is a chemical modification of the base moiety of the nucleotides of the RNA. In this context, nucleotide analogues or modifications are preferably selected from nucleotide analogues which are applicable for transcription and/or translation.

In particularly preferred embodiments, the nucleotide analogues/modifications which may be incorporated into a modified RNA as described herein are preferably selected from 2-amino-6-chloropurineriboside-5′-triphosphate, 2-Aminopurine-riboside-5′-triphosphate; 2-aminoadenosine-5′-triphosphate, 2′-Amino-2′-deoxycytidine-triphosphate, 2-thiocytidine-5′-triphosphate, 2-thiouridine-5′-triphosphate, 2′-Fluorothymidine-5′-triphosphate, 2′-O-Methyl-inosine-5′-triphosphate 4-thiouridine-5′-triphosphate, 5-aminoallylcytidine-5′-triphosphate, 5-aminoallyluridine-5′-triphosphate, 5-bromocytidine-5′-triphosphate, 5-bromouridine-5′-triphosphate, 5-Bromo-2′-deoxycytidine-5′-triphosphate, 5-Bromo-2′-deoxyuridine-5′-triphosphate, 5-iodocytidine-5′-triphosphate, 5-Iodo-2′-deoxycytidine-5′-triphosphate, 5-iodouridine-5′-triphosphate, 5-Iodo-2′-deoxyuridine-5′-triphosphate, 5-methylcytidine-5′-triphosphate, 5-methyluridine-5′-triphosphate, 5-Propynyl-2′-deoxycytidine-5′-triphosphate, 5-Propynyl-2′-deoxyuridine-5′-triphosphate, 6-azacytidine-5′-triphosphate, 6-azauridine-5′-triphosphate, 6-chloropurineriboside-5′-triphosphate, 7-deazaadenosine-5′-triphosphate, 7-deazaguanosine-5′-triphosphate, 8-azaadenosine-5′-triphosphate, 8-azidoadenosine-5′-triphosphate, benzimidazole-riboside-5′-triphosphate, N1-methyladenosine-5′-triphosphate, N1-methylguanosine-5′-triphosphate, N6-methyladenosine-5′-triphosphate, O6-methylguanosine-5′-triphosphate, pseudouridine-5′-triphosphate, or puromycin-5′-triphosphate, xanthosine-5′-triphosphate. Particular preference is given to nucleotides for base modifications selected from the group of base-modified nucleotides consisting of 5-methylcytidine-5′-triphosphate, 7-deazaguanosine-5′-triphosphate, 5-bromocytidine-5′-triphosphate, and pseudouridine-5′-triphosphate, pyridin-4-one ribonucleoside, 5-aza-uridine, 2-thio-5-aza-uridine, 2-thiouridine, 4-thio-pseudouridine, 2-thio-pseudouridine, 5-hydroxyuridine, 3-methyluridine, 5-carboxymethyl-uridine, 1-carboxymethyl-pseudouridine, 5-propynyl-uridine, 1-propynyl-pseudouridine, 5-taurinomethyluridine, 1-taurinomethyl-pseudouridine, 5-taurinomethyl-2-thio-uridine, 1-taurinomethyl-4-thio-uridine, 5-methyl-uridine, 1-methyl-pseudouridine, 4-thio-1-methyl-pseudouridine, 2-thio-1-methyl-pseudouridine, 1-methyl-1-deaza-pseudouridine, 2-thio-1-methyl-1-deaza-pseudouridine, dihydrouridine, dihydropseudouridine, 2-thio-dihydrouridine, 2-thio-dihydropseudouridine, 2-methoxyuridine, 2-methoxy-4-thio-uridine, 4-methoxy-pseudouridine, and 4-methoxy-2-thio-pseudouridine, 5-aza-cytidine, pseudoisocytidine, 3-methyl-cytidine, N4-acetylcytidine, 5-formylcytidine, N4-methylcytidine, 5-hydroxymethylcytidine, 1-methyl-pseudoisocytidine, pyrrolo-cytidine, pyrrolo-pseudoisocytidine, 2-thio-cytidine, 2-thio-5-methyl-cytidine, 4-thio-pseudoisocytidine, 4-thio-1-methyl-pseudoisocytidine, 4-thio-1-methyl-1-deaza-pseudoisocytidine, 1-methyl-1-deaza-pseudoisocytidine, zebularine, 5-aza-zebularine, 5-methyl-zebularine, 5-aza-2-thio-zebularine, 2-thio-zebularine, 2-methoxy-cytidine, 2-methoxy-5-methyl-cytidine, 4-methoxy-pseudoisocytidine, and 4-methoxy-1-methyl-pseudoisocytidine, 2-aminopurine, 2, 6-diaminopurine, 7-deaza-adenine, 7-deaza-8-aza-adenine, 7-deaza-2-aminopurine, 7-deaza-8-aza-2-aminopurine, 7-deaza-2,6-diaminopurine, 7-deaza-8-aza-2,6-diaminopurine, 1-methyladenosine, N6-methyladenosine, N6-isopentenyladenosine, N6-(cis-hydroxyisopentenyl)adenosine, 2-methylthio-N6-(cis-hydroxyisopentenyl) adenosine, N6-glycinylcarbamoyladenosine, N6-threonylcarbamoyladenosine, 2-methylthio-N6-threonyl carbamoyladenosine, N6,N6-dimethyladenosine, 7-methyladenine, 2-methylthio-adenine, and 2-methoxy-adenine, inosine, 1-methyl-inosine, wyosine, wybutosine, 7-deaza-guanosine, 7-deaza-8-aza-guanosine, 6-thio-guanosine, 6-thio-7-deaza-guanosine, 6-thio-7-deaza-8-aza-guanosine, 7-methyl-guanosine, 6-thio-7-methyl-guanosine, 7-methylinosine, 6-methoxy-guanosine, 1-methylguanosine, N2-methylguanosine, N2,N2-dimethylguanosine, 8-oxo-guanosine, 7-methyl-8-oxo-guanosine, 1-methyl-6-thio-guanosine, N2-methyl-6-thio-guanosine, and N2,N2-dimethyl-6-thio-guanosine, 5′-O-(1-thiophosphate)-adenosine, 5′-O-(1-thiophosphate)-cytidine, 5′-O-(1-thiophosphate)-guanosine, 5′-O-(1-thiophosphate)-uridine, 5′-O-(1-thiophosphate)-pseudouridine, 6-aza-cytidine, 2-thio-cytidine, alpha-thio-cytidine, Pseudo-iso-cytidine, 5-aminoallyl-uridine, 5-iodo-uridine, N1-methyl-pseudouridine, 5,6-dihydrouridine, alpha-thio-uridine, 4-thio-uridine, 6-aza-uridine, 5-hydroxy-uridine, deoxy-thymidine, 5-methyl-uridine, Pyrrolo-cytidine, inosine, alpha-thio-guanosine, 6-methyl-guanosine, 5-methyl-cytdine, 8-oxo-guanosine, 7-deaza-guanosine, N1-methyl-adenosine, 2-amino-6-Chloro-purine, N6-methyl-2-amino-purine, Pseudo-iso-cytidine, 6-Chloro-purine, N6-methyl-adenosine, alpha-thio-adenosine, 8-azido-adenosine, 7-deaza-adenosine.

In some embodiments, the at least one modified nucleotide is selected from pseudouridine, N1-methylpseudouridine, N1-ethylpseudouridine, 2-thiouridine, 4′-thiouridine, 5-methylcytosine, 5-methyluridine, 2-thio-1-methyl-1-deaza-pseudouridine, 2-thio-1-methyl-pseudouridine, 2-thio-5-aza-uridine, 2-thio-dihydropseudouridine, 2-thio-dihydrouridine, 2-thio-pseudouridine, 4-methoxy-2-thio-pseudouridine, 4-methoxy-pseudouridine, 4-thio-1-methyl-pseudouridine, 4-thio-pseudouridine, 5-aza-uridine, dihydropseudouridine, 5-methoxyuridine and 2′-O-methyl uridine.

In some embodiments, 100% of the uracil in the coding sequence as defined herein have a chemical modification, preferably a chemical modification is in the 5-position of the uracil.

Particularly preferred in the context of the invention are pseudouridine (ψ), N1-methylpseudouridine (m1ψ), 5-methylcytosine, and 5-methoxyuridine.

In some embodiments, however, a polynucleotide molecule of the embodiments does not include any N1-methylpseudouridine (m1ψ) substituted positions. In further aspects, a polynucleotide molecule of the embodiments does not include any pseudouridine (ψ), N1-methylpseudouridine (m1ψ), 5-methylcytosine, and 5-methoxyuridine substituted position. In still further aspects, a polynucleotide molecule of the embodiments comprises a coding sequence that consists only of G, C, A and U nucleotides.

Incorporating modified nucleotides such as pseudouridine (ψ), N1-methylpseudouridine (m1ψ), 5-methylcytosine, and/or 5-methoxyuridine into the coding sequence of the RNA may be advantageous as unwanted innate immune responses (upon administration of the coding RNA or the vaccine) may be adjusted or reduced (if required).

In some embodiments, the RNA comprises at least one coding sequence encoding a SARS-CoV-2 antigenic protein as defined herein, wherein said coding sequence comprises at least one modified nucleotide selected from pseudouridine (ψ) and N1-methylpseudouridine (m1ψ), preferably wherein all uracil nucleotides are replaced by pseudouridine (ψ) nucleotides and/or N1-methylpseudouridine (m1ψ) nucleotides.

In preferred embodiments, the RNA does not comprise N1-methylpseudouridine (m1ψ) substituted positions. In further embodiments, the RNA does not comprise pseudouridine (ψ), N1-methylpseudouridine (m1ψ), 5-methylcytosine, and 5-methoxyuridine substituted position.

In preferred embodiments, the RNA comprises a coding sequence that consists only of G, C, A and U nucleotides and therefore does not comprise modified nucleotides (except of the Cap analogue)

Nucleic Acid, Preferably mRNA Constructs Suitable for a Coronavirus Vaccine:

In various embodiments the nucleic acid, preferably the mRNA comprises, preferably in 5′- to 3′-direction, the following elements:

A) 5′-cap structure, preferably as specified herein;

B) 5′-terminal start element, preferably as specified herein;

C) optionally, a 5′-UTR, preferably as specified herein;

D) a ribosome binding site, preferably as specified herein;

E) at least one coding sequence, preferably as specified herein;

F) 3′-UTR, preferably as specified herein;

G) optionally, poly(A) sequence, preferably as specified herein;

H) optionally, poly(C) sequence, preferably as specified herein;

I) optionally, histone stem-loop preferably as specified herein;

J) optionally, 3′-terminal sequence element, preferably as specified herein.

In preferred embodiments the nucleic acid, preferably the mRNA, comprises the following elements preferably in 5′- to 3′-direction:

• A) 5′-cap structure selected from m7G(5′), m7G(5′)ppp(5′)(2′OMeA), or m7G(5′)ppp(5′)(2′OMeG);


• B) 5′-terminal start element selected from SEQ ID NOs: 176 or 177 or fragments or variants thereof;


• C) optionally, a 5′-UTR derived from a HSD17B4 gene;


• D) a ribosome binding site selected from SEQ ID NOs: 180, 181, 22845-22847 or fragments or variants thereof;


• E) at least one coding sequence selected from SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants thereof;


• F) 3′-UTR derived from a 3′-UTR of a PSMB3 gene or an alpha-globin gene (“muag”);


• G) optionally, poly(A) sequence comprising about 30 to about 500 adenosines;


• H) optionally, poly(C) sequence comprising about 10 to about 100 cytosines;


• I) optionally, histone stem-loop selected from SEQ ID NOs: 178 or 179;


• J) optionally, 3′-terminal sequence element selected from SEQ ID NOs: 182-230.

In particularly preferred embodiments the nucleic acid, preferably the mRNA, comprises the following elements in 5′- to 3′-direction:

• A) cap1 structure as defined herein;


• B) coding sequence selected from SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants thereof;


• C) 3′-UTR derived from a 3′-UTR of a muag gene as defined herein, preferably according to SEQ ID NO: 267 or 268, 22896-22901, 22906-22911;


• D) poly(A) sequence comprising about 64 A nucleotides.


• E) poly(C) sequence comprising about 10 to about 100 cytosines;


• F) histone stem-loop selected from SEQ ID NOs: 178 or 179;

In preferred embodiments the nucleic acid, preferably the mRNA, comprises the following elements in 5′- to 3′-direction:

• A) cap1 structure as defined herein;


• B) 5′-UTR derived from a HSD17B4 gene as defined herein, preferably according to SEQ ID NO: 231 or 232;


• C) coding sequence selected from SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants thereof;


• D) 3′-UTR derived from a 3′-UTR of a PSMB3 gene as defined herein, preferably according to SEQ ID NO: 253 or 254;


• E) poly(A) sequence comprising about 64 A nucleotides.


• F) optionally a poly(C) sequence comprising about 10 to about 100 cytosines;


• G) histone stem-loop selected from SEQ ID NOs: 178 or 179;


• H) optionally, 3′-terminal sequence element SEQ ID NOs: 182-230.

In particularly preferred embodiments the nucleic acid, preferably the mRNA, comprises the following elements in 5′- to 3′-direction:

• A) cap1 structure as defined herein;


• B) 5′-UTR derived from a HSD17B4 gene as defined herein, preferably according to SEQ ID NO: 231 or 232;


• C) coding sequence selected from SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants thereof;


• D) 3′-UTR derived from a 3′-UTR of a PSMB3 gene as defined herein, preferably according to SEQ ID NO: 253 or 254;


• E) a histone stem-loop selected from SEQ ID NOs: 178 or 179;


• F) poly(A) sequence comprising about 100 A nucleotides, preferably representing the 3′ terminus.

In further preferred embodiments the nucleic acid, preferably the mRNA, comprises the following elements in 5′- to 3′-direction:

• A) cap1 structure as defined herein;


• B) 5′-UTR derived from a HSD17B4 gene as defined herein, preferably according to SEQ ID NO: 231 or 232;


• C) coding sequence selected from SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants thereof;


• D) 3′-UTR derived from a 3′-UTR of a PSMB3 gene as defined herein, preferably according to SEQ ID NO: 253 or 254;


• F) poly(A) sequence comprising about 100 A nucleotides, preferably representing the 3′ terminus.

In further preferred embodiments the nucleic acid, preferably the mRNA, comprises the following elements in 5′- to 3′-direction:

• A) cap1 structure as defined herein;


• B) 5′-UTR derived from a SLC7A3 gene as defined herein, preferably according to SEQ ID NO: 245 or 246;


• C) coding sequence selected from SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants thereof;


• D) 3′-UTR derived from a 3′-UTR of a PSMB3 gene as defined herein, preferably according to SEQ ID NO: 253 or 254;


• E) optionally a histone stem-loop selected from SEQ ID NOs: 178 or 179;


• F) poly(A) sequence comprising about 100 A nucleotides, preferably representing the 3′ terminus.

In further preferred embodiments the nucleic acid, preferably the mRNA, comprises the following elements in 5′- to 3′-direction:

• A) cap1 structure as defined herein;


• B) 5′-UTR derived from a RPL31 gene as defined herein, preferably according to SEQ ID NO: 243 or 243;


• C) coding sequence selected from SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants thereof;


• D) 3′-UTR derived from a 3′-UTR of a RPS9 gene as defined herein, preferably according to SEQ ID NO: 263 or 264;


• E) optionally a histone stem-loop selected from SEQ ID NOs: 178 or 179;


• F) poly(A) sequence comprising about 100 A nucleotides, preferably representing the 3′ terminus.

Preferred nucleic acid sequences, preferably mRNA sequences of the invention are provided in Table 3a. Therein, each row represents a specific suitable SARS-CoV-2 (nCoV-2019) construct of the invention (compare with Table 1), wherein the description of the SARS-CoV-2 construct is indicated in column A of Table 3a and the SEQ ID NOs of the amino acid sequence of the respective SARS-CoV-2 construct is provided in column B. The corresponding SEQ ID NOs of the coding sequences encoding the respective SARS-CoV-2 constructs are provided in in Table 1. Further information is provided under <223> identifier of the respective SEQ ID NOs in the sequence listing.

The corresponding nucleic acid, preferably coding RNA sequences, in particular mRNA sequences comprising preferred coding sequences are provided in columns C and D, wherein column C provides nucleic acid sequences with an UTR combination “HSD17B4/PSMB3” as defined herein, wherein column D provides nucleic acid sequences with an “alpha-globin” 3′ UTR as defined herein.

Further preferred nucleic acid sequences, preferably mRNA sequences of the invention are provided in Table 3b. Therein, each column represents a specific suitable SARS-CoV-2 (nCoV-2019) construct of the invention (compare with Table 1 and Table 3a), wherein column B represents “Full-length spike protein; S”, row 1 of Table 1 and Table 3a and column C “Stabilized spike protein; S_stab_PP”, compare with row 2 of Table 1 and Table 3a.

The SEQ ID NOs of the amino acid sequence of the respective SARS-CoV-2 construct are provided in row 1. The corresponding SEQ ID NOs of the coding sequences encoding the respective SARS-CoV-2 constructs are provided in in Table 1. Further information is provided under <223> identifier of the respective SEQ ID NOs in the sequence listing.

The corresponding nucleic acid, preferably coding RNA sequences, in particular mRNA sequences comprising preferred coding sequences are provided in rows 2-16, wherein each row provides nucleic acid sequences with UTR combinations and suitable 3′ ends.

In preferred embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 or a fragment or variant of any of these sequences. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing, and in Table 3a (see in particular Column C and D) and Table 3b (see in particular rows 2-16).

In particularly preferred embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 162-175, 12676-13147, 14160-14177, 22786-22839, 23189-23404, or a fragment or variant of any of these sequences. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing, and in Table 3a (see in particular Column D), Table 3b (row 2).

In particularly preferred embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-161, 12204-12675, 14142-14159, 22786-22812, 23409-23624, 24729-24944, or a fragment or variant of any of these sequences. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing, and in Table 3a (see in particular Column C) and Table 3b (see rows 3, 7).

In particularly preferred embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 149-154, 156-161, 163-168, 170-175, 12338, 12352, 12541, 12555, 12810, 12824, 13013, 13027, 22786, 22792, 22794, 22796, 22798, 22800, 22802, 22804, 22806, 22808, 22810, 22812, 22813, 22819, 22821, 22823, 22825, 22827, 22829, 22831, 22833, 22835, 22837, 22839, 23517-23624, 23297-23404, 24837-24944 or a fragment or variant of any of these sequences. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing and in Table 3a (see Column C and D, rows 2 and 6) and Table 3b (see Column C).

In even more preferred embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 149, 156, 12338, 150, 157, 151, 158, 12541, 163, 170, 12810, 164, 171, 165, 172, 13013, 12342-12351, 12545-12554, 12814-12823, 13017-13026, 14133 or a fragment or variant of any of these sequences. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing and in Table 3a and 3b.

In even more preferred embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 149, 150, 151, 163, 164, 165 or a fragment or variant of any of these sequences. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing and in Table 3 (see Column C and D, row 2).

In a particularly preferred embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 163.

In a further particularly preferred embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 149.

In a further particularly preferred embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 24837.

In a further preferred embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 23311, 23531, 24851.

In a further preferred embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 23310, 23530, 24850.

In a further preferred embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 23313, 23533, 24853, 23314, 23534, 24854.

In a further embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 26633.

In a further embodiment, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 26907.

In further preferred embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937, wherein said RNA sequences comprise a cap1 structure as defined herein. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing and in Table 3a and 3b.

In further embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937, wherein at least one, preferably all uracil nucleotides in said RNA sequences are replaced by pseudouridine (ψ) nucleotides and/or N1-methylpseudouridine (m1ψ) nucleotides. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing and in Table 3a and 3b.

In further embodiments, the nucleic acid, preferably the RNA, comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937, wherein said RNA sequences comprise a cap1 structure as defined herein, and, wherein at least one, preferably all uracil nucleotides in said RNA sequences are replaced by pseudouridine (ψ) nucleotides and/or N1-methylpseudouridine (m1ψ) nucleotides. Further information regarding respective nucleic acid sequences is provided under <223> identifier of the respective SEQ ID NO in the sequence listing and in Table 3a and 3b.

As outlined throughout the specification, additional information regarding suitable amino acid sequences or nucleic acid sequences (coding sequences, DNA sequences, RNA sequences) may also be derived from the sequence listing, in particular from the details provided therein under identifier <223> as explained in the following.

In particular embodiments, the nucleic acid of the invention is an RNA, wherein the RNA may be prepared using any method known in the art, including chemical synthesis such as e.g. solid phase RNA synthesis, as well as in vitro methods, such as RNA in vitro transcription reactions. Accordingly, in a preferred embodiment, the RNA is obtained by RNA in vitro transcription.

Accordingly, in preferred embodiments, the nucleic acid of the invention is preferably an in vitro transcribed RNA.

The terms “RNA in vitro transcription” or “in vitro transcription” relate to a process wherein RNA is synthesized in a cell-free system (in vitro). RNA may be obtained by DNA-dependent in vitro transcription of an appropriate DNA template, which according to the present invention is a linearized plasmid DNA template or a PCR-amplified DNA template. The promoter for controlling RNA in vitro transcription can be any promoter for any DNA-dependent RNA polymerase. Particular examples of DNA-dependent RNA polymerases are the T7, T3, SP6, or Syn5 RNA polymerases. In a preferred embodiment of the present invention the DNA template is linearized with a suitable restriction enzyme, before it is subjected to RNA in vitro transcription.

Reagents used in RNA in vitro transcription typically include: a DNA template (linearized plasmid DNA or PCR product) with a promoter sequence that has a high binding affinity for its respective RNA polymerase such as bacteriophage-encoded RNA polymerases (T7, T3, SP6, or Syn5); ribonucleotide triphosphates (NTPs) for the four bases (adenine, cytosine, guanine and uracil); optionally, a cap analogue as defined herein; optionally, further modified nucleotides as defined herein; a DNA-dependent RNA polymerase capable of binding to the promoter sequence within the DNA template (e.g. T7, T3, SP6, or Syn5 RNA polymerase); optionally, a ribonuclease (RNase) inhibitor to inactivate any potentially contaminating RNase; optionally, a pyrophosphatase to degrade pyrophosphate, which may inhibit RNA in vitro transcription; MgCl2, which supplies Mg2+ ions as a co-factor for the polymerase; a buffer (TRIS or HEPES) to maintain a suitable pH value, which can also contain antioxidants (e.g. DTT), and/or polyamines such as spermidine at optimal concentrations, e.g. a buffer system comprising TRIS-Citrate as disclosed in WO2017/109161.

In preferred embodiments, the cap1 structure of the RNA of the invention is formed using co-transcriptional capping using tri-nucleotide cap analogues m7G(5′)ppp(5′)(2′OMeA)pG or m7G(5′)ppp(5′)(2′OMeG)pG. A preferred cap1 analogue that may suitably be used in manufacturing the coding RNA of the invention is m7G(5′)ppp(5′)(2′OMeA)pG.

In a particularly preferred embodiment, the cap1 structure of the RNA of the invention is formed using co-transcriptional capping using tri-nucleotide cap analogue 3′OMe-m7G(5′)ppp(5′)(2′OMeA)pG.

In other embodiments, a capO structure of the RNA of the invention is formed using co-transcriptional capping using cap analogue 3′OMe-m7G(5′)ppp(5′)G.

In additional embodiments, the nucleotide mixture used in RNA in vitro transcription may additionally comprise modified nucleotides as defined herein. In that context, preferred modified nucleotides may be selected from pseudouridine (ψ), N1-methylpseudouridine (m1ψ), 5-methylcytosine, and 5-methoxyuridine. In particular embodiments, uracil nucleotides in the nucleotide mixture are replaced (either partially or completely) by pseudouridine (ψ) and/or N1-methylpseudouridine (m1ψ) to obtain a modified RNA.

In preferred embodiments, the nucleotide mixture used in RNA in vitro transcription does not comprise modified nucleotides as defined herein. In preferred embodiments, the nucleotide mixture used in RNA in vitro transcription does only comprise G, C, A and U nucleotides, and, optionally, a cap analog as defined herein.

In preferred embodiments, the nucleotide mixture (i.e. the fraction of each nucleotide in the mixture) used for RNA in vitro transcription reactions may be optimized for the given RNA sequence, preferably as described WO2015/188933. In this context the in vitro transcription has been performed in the presence of a sequence optimized nucleotide mixture and optionally a cap analog, preferably wherein the sequence optimized nucleotide mixture does not comprise chemically modified nucleotides.

In this context a sequence-optimized nucleoside triphosphate (NTP) mix is a mixture of nucleoside triphosphates (NTPs) for use in an in vitro transcription reaction of an RNA molecule of a given sequence comprising the four nucleoside triphosphates (NTPs) GTP, ATP, CTP and UTP, wherein the fraction of each of the four nucleoside triphosphates (NTPs) in the sequence-optimized nucleoside triphosphate (NTP) mix corresponds to the fraction of the respective nucleotide in said RNA molecule. If a ribonucleotide is not present in the RNA molecule, the corresponding nucleoside triphosphate is also not present in the sequence-optimized nucleoside triphosphate (NTP) mix.

In embodiments where more than one different RNA as defined herein have to be produced, e.g. where 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different RNAs have to be produced (see second aspect), procedures as described in WO2017/109134 may suitably be used.

In the context of nucleic acid-based vaccine production, it may be required to provide GMP-grade nucleic acids, e.g. a GMP grade RNA or DNA. GMP-grade RNA or DNA may be produced using a manufacturing process approved by regulatory authorities. Accordingly, in a particularly preferred embodiment, RNA production is performed under current good manufacturing practice (GMP), implementing various quality control steps on DNA and RNA level, preferably according to WO2016/180430. In preferred embodiments, the RNA of the invention is a GMP-grade RNA, particularly a GMP-grade mRNA. Accordingly, an RNA for a vaccine is preferably a GMP grade RNA.

The obtained RNA products are preferably purified using PureMessenger® (CureVac, Tubingen, Germany; RP-HPLC according to WO2008/077592) and/or tangential flow filtration (as described in WO2016/193206) and/or oligo d(T) purification (see WO2016/180430).

Preferably, the RNA according to the invention is purified using RP-HPLC, preferably using Reversed-Phase High pressure liquid chromatography (RP-HPLC) with a macroporous styrene/divinylbenzene column (e.g. particle size 30 μm, pore size 4000 A and additionally using a filter cassette with a cellulose based membrane with a molecular weight cutoff of about 100 kDa.

In this context it is particularly preferred that the purified RNA has been purified by RP-HPLC and/or TFF which results in about 5%, 10%, or 20% less double stranded RNA side products as in RNA that has not been purified with RP-HPLC and/or TFF.

Alternatively, the purified RNA that has been purified by RP-HPLC and/or TFF comprises about 5%, 10%, or 20% less double stranded RNA side products as an RNA that has been purified with Oligo dT purification, precipitation, filtration and/or anion exchange chromatography.

In a further preferred embodiment, the nucleic acid, preferably the RNA, is lyophilized (e.g. according to WO2016/165831 or WO2011/069586) to yield a temperature stable dried nucleic acid (powder) as defined herein (e.g. RNA or DNA). The nucleic acid of the invention, particularly the RNA may also be dried using spray-drying or spray-freeze drying (e.g. according to WO2016/184575 or WO2016/184576) to yield a temperature stable RNA (powder) as defined herein. Accordingly, in the context of manufacturing and purifying nucleic acid, in particular RNA, the disclosures of WO2017/109161, WO2015/188933, WO2016/180430, WO2008/077592, WO2016/193206, WO2016/165831, WO2011/069586, WO2016/184575, and WO2016/184576 are incorporated herewith by reference.

Accordingly, in preferred embodiments, the nucleic acid is a dried nucleic acid, particularly a dried RNA.

The term “dried RNA” as used herein has to be understood as RNA that has been lyophilized, or spray-dried, or spray-freeze dried as defined above to obtain a temperature stable dried RNA (powder).

In preferred embodiments, the nucleic acid of the invention is a purified nucleic acid, particularly a purified RNA.

The term “purified nucleic acid” as used herein has to be understood as nucleic acid which has a higher purity after certain purification steps than the starting material. Typical impurities that are essentially not present in purified nucleic acid comprise peptides or proteins, spermidine, BSA, abortive nucleic acid sequences, nucleic acid fragments, free nucleotides, bacterial impurities, or impurities derived from purification procedures. Accordingly, it is desirable in this regard for the “degree of nucleic acid purity” to be as close as possible to 100%. It is also desirable for the degree of nucleic acid purity that the amount of full-length nucleic acid is as close as possible to 100%. Accordingly “purified nucleic acid” as used herein has a degree of purity of more than 75%, 80%, 85%, very particularly 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% and most favorably 99% or more. The degree of purity may for example be determined by an analytical HPLC, wherein the percentages provided above correspond to the ratio between the area of the peak for the target nucleic acid and the total area of all peaks representing the by-products. Alternatively, the degree of purity may for example be determined by an analytical agarose gel electrophoresis or capillary gel electrophoresis.

In preferred embodiments, the nucleic acid of the invention is a purified RNA.

The term “purified RNA” or “purified mRNA” as used herein has to be understood as RNA which has a higher purity after certain purification steps (e.g. HPLC, TFF, Oligo d(T) purification, precipitation steps) than the starting material (e.g. in vitro transcribed RNA). Typical impurities that are essentially not present in purified RNA comprise peptides or proteins (e.g. enzymes derived from DNA dependent RNA in vitro transcription, e.g. RNA polymerases, RNases, pyrophosphatase, restriction endonuclease, DNase), spermidine, BSA, abortive RNA sequences, RNA fragments (short double stranded RNA fragments, abortive sequences etc.), free nucleotides (modified nucleotides, conventional NTPs, cap analogue), template DNA fragments, buffer components (HEPES, TRIS, MgCl2) etc. Other potential impurities that may be derived from e.g. fermentation procedures comprise bacterial impurities (bioburden, bacterial DNA) or impurities derived from purification procedures (organic solvents etc.). Accordingly, it is desirable in this regard for the “degree of RNA purity” to be as close as possible to 100%. It is also desirable for the degree of RNA purity that the amount of full-length RNA transcripts is as close as possible to 100%. Accordingly, “purified RNA” as used herein has a degree of purity of more than 75%, 80%, 85%, very particularly 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% and most favorably 99% or more. The degree of purity may for example be determined by an analytical HPLC, wherein the percentages provided above correspond to the ratio between the area of the peak for the target RNA and the total area of all peaks representing the by-products. Alternatively, the degree of purity may for example be determined by an analytical agarose gel electrophoresis or capillary gel electrophoresis.

In particularly preferred embodiments where the nucleic acid is an RNA, the RNA has been purified by RP-HPLC and/or TFF to remove double-stranded RNA, non-capped RNA and/or RNA fragments.

The formation of double stranded RNA as side products during e.g. RNA in vitro transcription can lead to an induction of the innate immune response, particularly IFNalpha which is the main factor of inducing fever in vaccinated subjects, which is of course an unwanted side effect. Current techniques for immunoblotting of dsRNA (via dot Blot, serological specific electron microscopy (SSEM) or ELISA for example) are used for detecting and sizing dsRNA species from a mixture of nucleic acids.

Suitably, the RNA of the invention has been purified by RP-HPLC and/or TFF as described herein to reduce the amount of dsRNA.

In preferred embodiments, the RNA of the invention comprises about 5%, 10%, or 20% less double stranded RNA side products as an RNA that has not been purified with RP-HPLC and/or TFF.

In preferred embodiments, the RP-HPLC and/or TFF purified RNA of the invention comprises about 5%, 10%, or 20% less double stranded RNA side products as an RNA that has been purified with Oligo dT purication, precipitation, filtration and/or AEX.

It has to be understood that “dried RNA” as defined herein and “purified RNA” as defined herein or “GMP-grade RNA” as defined herein may have superior stability characteristics (in vitro, in vivo) and improved efficiency (e.g. better translatability of the mRNA in vivo) and are therefore particularly suitable for a medical purpose, e.g. a vaccine.

Following co-transcriptional capping as defined herein, and following purification as defined herein, the capping degree of the obtained RNA may be determined using capping assays as described in published PCT application WO2015/101416, in particular, as described in claims 27 to 46 of published PCT application WO2015/101416 can be used. Alternatively, a capping assays described in PCT/EP2018/08667 may be used.

In embodiments, an automated device for performing RNA in vitro transcription may be used to produce and purify the nucleic acid of the invention. Such a device may also be used to produce the composition or the vaccine (see aspects 2 and 3). Preferably, a device as described in WO2020002598, in particular, a device as described in claims 1 to 59 and/or 68 to 76 of WO2020002598 (and FIGS. 1-18) may suitably be used.

The methods described herein may preferably applied to a method of producing an RNA composition or vaccine as described in further detail below.

Composition, Pharmaceutical Composition:

A second aspect relates to a composition comprising at least one nucleic acid of the first aspect.

Notably, embodiments relating to the composition of the second aspect may likewise be read on and be understood as suitable embodiments of the vaccine of the fourth aspect. Also, embodiments relating to the vaccine of the fourth aspect may likewise be read on and be understood as suitable embodiments of the composition of the second aspect (comprising the nucleic acid of the first aspect). Furthermore, features and embodiments described in the context of the first aspect (the nucleic acid of the invention) have to be read on and have to be understood as suitable embodiments of the composition of the second aspect.

In preferred embodiments, the composition comprises at least one nucleic acid according to the first aspect encoding at least one antigenic peptide or protein that is or is derived from a SARS-CoV-2 (formerly an nCoV-2019) coronavirus, or an immunogenic fragment or immunogenic variant thereof.

In preferred embodiments, the composition comprises at least one nucleic acid encoding at least one antigenic peptide or protein that is or is derived from a SARS-CoV-2 coronavirus, or an immunogenic fragment or immunogenic variant thereof according to the first aspect, wherein said composition is to be, preferably, administered intramuscularly or intradermal.

Preferably, intramuscular or intradermal administration of said composition results in expression of the encoded SARS-CoV-2 antigen construct in a subject. In embodiments where the nucleic acid is an RNA, administration of said composition results in translation of the RNA and to a production of the encoded SARS-CoV-2 antigen in a subject. In embodiments where the nucleic acid is a DNA (e.g. plasmid DNA, adenovirus DNA), administration of said composition results in transcription of the DNA into RNA, and to a subsequent translation of the RNA into the encoded SARS-CoV-2 coronavirus antigen in a subject.

Preferably, the composition of the second aspect is suitable for a vaccine, in particular, suitable for a coronavirus vaccine, preferably a SARS-CoV-2 (nCoV-2019) vaccine.

In the context of the invention, a “composition” refers to any type of composition in which the specified ingredients (e.g. nucleic acid encoding at least one antigenic peptide or protein that is or is derived from a SARS-CoV-2 coronavirus, e.g. an RNA or a DNA, e.g. in association with a polymeric carrier or LNP) may be incorporated, optionally along with any further constituents, usually with at least one pharmaceutically acceptable carrier or excipient. The composition may be a dry composition such as a powder or granules, or a solid unit such as a lyophilized form. Alternatively, the composition may be in liquid form, and each constituent may be independently incorporated in dissolved or dispersed (e.g. suspended or emulsified) form.

In a preferred embodiment of the second aspect, the composition comprises at least one nucleic acid (e.g. DNA or RNA) of the first aspect, preferably an RNA, and optionally, at least one pharmaceutically acceptable carrier or excipient.

In embodiments of the second aspect, the composition comprises at least one nucleic acid of the first aspect, preferably a plasmid DNA, adenovirus DNA, and optionally, at least one pharmaceutically acceptable carrier or excipient.

In preferred embodiments of the second aspect, the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably an RNA, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-13147, 13514, 13515, 13519, 13520, 14124-14177, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23184, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 and, optionally, at least one pharmaceutically acceptable carrier or excipient.

In particularly preferred embodiments of the second aspect, the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably an RNA, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 and, optionally, at least one pharmaceutically acceptable carrier or excipient.

Most preferably the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably an RNA, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO. 163.

Most preferably the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably an RNA, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO. 149.

In further particularly preferred embodiments, the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably an RNA, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO. 24837, 23311, 23531, 23310, 23530, 23313, 23533.

In further embodiments, the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably an RNA, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO. 26633, 26907.

In particularly preferred embodiments of the second aspect, the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably an RNA, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 149-151, 163-165, 24837, 23311, 23531, 24851, 23310, 23530, 23313, 23533 and, optionally, at least one pharmaceutically acceptable carrier or excipient.

The term “pharmaceutically acceptable carrier” or “pharmaceutically acceptable excipient” as used herein preferably includes the liquid or non-liquid basis of the composition for administration. If the composition is provided in liquid form, the carrier may be water, e.g. pyrogen-free water; isotonic saline or buffered (aqueous) solutions, e.g. phosphate, citrate etc. buffered solutions. Water or preferably a buffer, more preferably an aqueous buffer, may be used, containing a sodium salt, preferably at least 50 mM of a sodium salt, a calcium salt, preferably at least 0.01 mM of a calcium salt, and optionally a potassium salt, preferably at least 3 mM of a potassium salt. According to preferred embodiments, the sodium, calcium and, optionally, potassium salts may occur in the form of their halogenides, e.g. chlorides, iodides, or bromides, in the form of their hydroxides, carbonates, hydrogen carbonates, or sulfates, etc. Examples of sodium salts include NaCl, NaI, NaBr, Na₂CO₃, NaHCO₃, Na₂SO₄, examples of the optional potassium salts include KCl, KI, KBr, K₂CO₃, KHCO₃, K₂SO₄, and examples of calcium salts include CaCl₂), CaI₂, CaBr₂, CaCO₃, CaSO₄, Ca(OH)₂.

Furthermore, organic anions of the aforementioned cations may be in the buffer. Accordingly, in embodiments, the nucleic acid composition may comprise pharmaceutically acceptable carriers or excipients using one or more pharmaceutically acceptable carriers or excipients to e.g. increase stability, increase cell transfection, permit the sustained or delayed, increase the translation of encoded coronavirus protein in vivo, and/or alter the release profile of encoded coronavirus protein in vivo. In addition to traditional excipients such as any and all solvents, dispersion media, diluents, or other liquid vehicles, dispersion or suspension aids, surface active agents, isotonic agents, thickening or emulsifying agents, preservatives, excipients of the present invention can include, without limitation, lipidoids, liposomes, lipid nanoparticles, polymers, lipoplexes, core-shell nanoparticles, peptides, proteins, cells transfected with polynucleotides, hyaluronidase, nanoparticle mimics and combinations thereof. In embodiments, one or more compatible solid or liquid fillers or diluents or encapsulating compounds may be used as well, which are suitable for administration to a subject. The term “compatible” as used herein means that the constituents of the composition are capable of being mixed with the at least one nucleic acid and, optionally, a plurality of nucleic acids of the composition, in such a manner that no interaction occurs, which would substantially reduce the biological activity or the pharmaceutical effectiveness of the composition under typical use conditions (e.g., intramuscular or intradermal administration). Pharmaceutically acceptable carriers or excipients must have sufficiently high purity and sufficiently low toxicity to make them suitable for administration to a subject to be treated. Compounds which may be used as pharmaceutically acceptable carriers or excipients may be sugars, such as, for example, lactose, glucose, trehalose, mannose, and sucrose; starches, such as, for example, corn starch or potato starch; dextrose; cellulose and its derivatives, such as, for example, sodium carboxymethylcellulose, ethylcellulose, cellulose acetate; powdered tragacanth; malt; gelatin; tallow; solid glidants, such as, for example, stearic acid, magnesium stearate; calcium sulfate; vegetable oils, such as, for example, groundnut oil, cottonseed oil, sesame oil, olive oil, corn oil and oil from theobroma; polyols, such as, for example, polypropylene glycol, glycerol, sorbitol, mannitol and polyethylene glycol; alginic acid.

The at least one pharmaceutically acceptable carrier or excipient of the composition may preferably be selected to be suitable for intramuscular or intradermal delivery/administration of said composition. Accordingly, the composition is preferably a pharmaceutical composition, suitably a composition for intramuscular administration.

Subjects to which administration of the compositions, preferably the pharmaceutical composition, is contemplated include, but are not limited to, humans and/or other primates; mammals, including commercially relevant mammals such as cattle, pigs, horses, sheep, cats, dogs, mice, and/or rats; and/or birds, including commercially relevant birds such as poultry, chickens, ducks, geese, and/or turkeys.

Pharmaceutical compositions of the present invention may suitably be sterile and/or pyrogen-free.

Multivalent Compositions of the Invention:

In embodiments, the composition (e.g. multivalent composition) as defined herein may comprise a plurality or at least more than one of the nucleic acid species, e.g. RNA species as defined in the context of the first aspect of the invention. Preferably, the composition as defined herein may comprise 2, 3, 4, 5, 6, 7, 8, 9, or 10 different nucleic acids each defined in the context of the first aspect.

In embodiments, the composition (e.g. multivalent composition) may comprise at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species as defined in the context of the first aspect, each encoding at least one antigenic peptide or protein derived from the same coronavirus, or a fragment or variant thereof. Particularly, said (genetically) same coronavirus expresses (essentially) the same repertoire of proteins or peptides, wherein all proteins or peptides have (essentially) the same amino acid sequence. Particularly, said (genetically) same coronavirus expresses essentially the same proteins, peptides or polyproteins, wherein these protein, peptide or polyproteins preferably do not differ in their amino acid sequence(s).

In embodiments, the composition (e.g. multivalent composition) comprises at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species as defined in the context of the first aspect, each encoding at least one peptide or protein derived from a genetically different coronavirus (e.g. a different coronavirus isolate), or a fragment or variant thereof. The terms “different” or “different coronavirus” as used throughout the present specification have to be understood as the difference between at least two respective coronavirus (e.g. a different coronavirus isolates), wherein the difference is manifested on the genome of the respective different coronavirus. Particularly, said (genetically) different coronavirus may express at least one different protein, peptide or polyprotein, wherein the at least one different protein, peptide or polyprotein differs in at least one amino acid.

In preferred embodiments the plurality or at least more than one of the nucleic acid sequences of the multivalent composition each encode a different spike protein, preferably a prefusion stabilized spike protein.

In this context it is particularly preferred that the different spike proteins or prefusion stabilized spike proteins are derived from different SARS-CoV-2 virus variants/isolates, wherein it is particularly preferred that the spike proteins are derived from B.1.1.7, B.1.351, P.1, or CAL.20C.

In this context it is further preferred that the different spike proteins or prefusion stabilized spike proteins have amino acid changes in the spike protein comprising:

(i) delH69, delV70, Y453F, D614G, I692V and M1229I;

(ii) delH69, delV70, delY144, N501Y, A570D, D614G, P681H, T716I, S982A and D1118H;

(iii) L18F, D80A, D215G, delL242, delA243, delL244, R246I, K417N, E484K, N501Y, D614G and A701V;

(iv) L18F, T20N, P26S, D138Y, R190S, K417T, E484K, N501Y, D614G, H655Y and T1027I; and/or

(v) S13I, W152C, L452R, and D614G.

In embodiments, the composition (e.g. multivalent composition) comprises 2, 3, 4 or 5 nucleic acid species (e.g. DNA or RNA), preferably RNA species, wherein said nucleic acid species comprise or consist of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-13147, 13514, 13515, 13519, 13520, 14124-14177, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23184, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 and, optionally, at least one pharmaceutically acceptable carrier or excipient, wherein each of the 2, 3, 4 or 5 nucleic acid species encode a different antigenic peptide or protein of a SARS-CoV-2 coronavirus.

Accordingly, in embodiments, the composition (e.g. multivalent composition) comprises two nucleic acid species (e.g. DNA or RNA), preferably RNA species, wherein the nucleic acid species comprise or consist of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 and, optionally, at least one pharmaceutically acceptable carrier or excipient, wherein each of the two nucleic acid species encode a different antigenic peptide or protein of a SARS-CoV-2 coronavirus.

In embodiments, the composition (e.g. multivalent composition) comprises three nucleic acid species (e.g. DNA or RNA), preferably RNA species, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 and, optionally, at least one pharmaceutically acceptable carrier or excipient, wherein each of the 2, 3, 4 or 5 nucleic acid species encode a different antigenic peptide or protein of a SARS-CoV-2 coronavirus.

In the following, particularly preferred embodiments of a multivalent composition are provided.

Preferably, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species of the multivalent composition each encode a different prefusion stabilized spike protein (as defined in the first aspect). Preferably, stabilization of the prefusion conformation is obtained by introducing two consecutive proline substitutions at residues K986 and V987 in the spike protein (Amino acid positions according to reference SEQ ID NO: 1). Accordingly, in preferred embodiments, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 pre-fusion stabilized spike proteins (S_stab) each comprises at least one prefusion stabilizing mutation, wherein the at least one prefusion stabilizing mutation comprises the following amino acid substitutions: K986P and V987P (amino acid positions according to reference SEQ ID NO: 1).

Accordingly, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species of the multivalent composition each encode a different prefusion stabilized spike protein, wherein the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more stabilized spike proteins are selected from amino acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10-26, 341-407, 609-1278, 13521-13587, 22738, 22740, 22742, 22744, 22746, 22748, 22750, 22752, 22754, 22756, 22758, 22947-22964 or an immunogenic fragment or immunogenic variant of any of these.

In preferred embodiments, the multivalent composition comprises one nucleic acid species comprising a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10, wherein the multivalent composition additionally comprises at least 2, 3, 4 further RNA species selected from

• i) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22961; and/or


• ii) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22960; and/or


• iii) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22963; and/or


• iv) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22941; and/or


• v) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22964.

In preferred embodiments, the multivalent composition comprises at least two nucleic acid species comprising a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10, 22961; 22960, 22963, 22941, 22964.

Preferably, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species of the multivalent composition comprise nucleic acid coding sequences each encoding a different prefusion stabilized spike protein, wherein the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more nucleic acid coding sequences are selected from nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 136-138, 140-143, 145-175, 11731-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants of any of these.

In preferred embodiments, the multivalent composition comprises one nucleic acid species comprising a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 137, wherein the multivalent composition additionally comprises at least 2, 3, 4 further RNA species selected from

• i) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23091; and/or


• ii) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23090; and/or


• iii) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23093; and/or


• iv) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22999; and/or


• v) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23094.

Preferably, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species of the multivalent composition comprise nucleic acid coding sequences each encoding a different prefusion stabilized spike protein, wherein the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more nucleic acid coding sequences are selected from RNA sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 149-151, 163-165, 12338, 12541, 12810-12813, 12901, 12931, 13013, 22792, 22794, 22796, 22798, 22802, 22804, 22806, 22810, 22813, 22819, 22821, 22823, 22825, 22827, 22829, 22831, 22833, 22835, 22837, 22839, 23297-23314, 23369, 23517-23520, 23523-23525, 23527, 23529, 23530, 23589, 23737, 23957, 24397, 24837, 25057, 25277, 25717, 26925-26937 or fragments or variants of any of these.

In preferred embodiments, the multivalent composition comprises one RNA species comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 163, wherein the multivalent composition additionally comprises at least 2, 3, 4 further RNA species selected from

• i) one RNA species comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23311; and/or


• ii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23310; and/or


• iii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23313; and/or


• iv) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: SEQ ID NO: 23219; and/or


• v) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23314;

wherein, preferably, each of the mRNA species comprise a Cap1 structure, and, optionally, each of the mRNA species do not comprise modified nucleotides.

In preferred embodiments, the multivalent composition comprises one RNA species comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 149 or 24837, wherein the multivalent composition additionally comprises at least 2, 3, 4 further RNA species selected from

• i) one RNA species comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23531 or 24851; and/or


• ii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23530 or 24850; and/or


• iii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23533 or 24853; and/or


• iv) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23439 or 24759; and/or


• v) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23534 or 24854;

wherein, preferably, each of the mRNA species comprise a Cap1 structure, and, optionally, each of the mRNA species do not comprise modified nucleotides.

In further preferred embodiments, the multivalent composition comprises at least two RNA species being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 149 or 24837, 23531 or 24851, 23530 or 24850, 23533 or 24853, 23439 or 24759 or 23534 or 24854.

In embodiments, the nucleic acid (e.g. DNA or RNA), preferably RNA species of the multivalent composition may be formulated separately (formulation as specified below). In preferred embodiments, the nucleic acid (e.g. DNA or RNA), preferably RNA species of the multivalent composition may be co-formulated separately (formulation as specified below).

Complexation:

In a preferred embodiment of the second aspect, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA, is complexed or associated with further compound to obtain a formulated composition. A formulation in that context may have the function of a transfection agent. A formulation in that context may also have the function of protecting the nucleic acid from degradation.

In a preferred embodiment of the second aspect, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA, and optionally the at least one further nucleic acid, is complexed or associated with, or at least partially complexed or partially associated with one or more cationic or polycationic compound, preferably cationic or polycationic polymer, cationic or polycationic polysaccharide, cationic or polycationic lipid, cationic or polycationic protein, cationic or polycationic peptide, or any combinations thereof.

The term “cationic or polycationic compound” as used herein will be recognized and understood by the person of ordinary skill in the art, and are for example intended to refer to a charged molecule, which is positively charged at a pH value ranging from about 1 to 9, at a pH value ranging from about 3 to 8, at a pH value ranging from about 4 to 8, at a pH value ranging from about 5 to 8, more preferably at a pH value ranging from about 6 to 8, even more preferably at a pH value ranging from about 7 to 8, most preferably at a physiological pH, e.g. ranging from about 7.2 to about 7.5. Accordingly, a cationic component, e.g. a cationic peptide, cationic protein, cationic polymer, cationic polysaccharide, cationic lipid may be any positively charged compound or polymer which is positively charged under physiological conditions. A “cationic or polycationic peptide or protein” may contain at least one positively charged amino acid, or more than one positively charged amino acid, e.g. selected from Arg, His, Lys or Orn. Accordingly, “polycationic” components are also within the scope exhibiting more than one positive charge under the given conditions.

Cationic or polycationic compounds, being particularly preferred in this context may be selected from the following list of cationic or polycationic peptides or proteins of fragments thereof: protamine, nucleoline, spermine or spermidine, or other cationic peptides or proteins, such as poly-L-lysine (PLL), poly-arginine, basic polypeptides, cell penetrating peptides (CPPs), including HIV-binding peptides, HIV-1 Tat (HIV), Tat-derived peptides, Penetratin, VP22 derived or analog peptides, HSV VP22 (Herpes simplex), MAP, KALA or protein transduction domains (PTDs), PpT620, prolin-rich peptides, arginine-rich peptides, lysine-rich peptides, MPG-peptide(s), Pep-1, L-oligomers, Calcitonin peptide(s), Antennapedia-derived peptides, pAntp, p151, FGF, Lactoferrin, Transportan, Buforin-2, Bac715-24, SynB, SynB(1), pVEC, hCT-derived peptides, SAP, or histones. More preferably, the nucleic acid (e.g. DNA or RNA), e.g. the coding RNA, preferably the mRNA, is complexed with one or more polycations, preferably with protamine or oligofectamine, most preferably with protamine.

In preferred embodiment, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed with protamine.

Further preferred cationic or polycationic compounds, which can be used as transfection or complexation agent may include cationic polysaccharides, for example chitosan, polybrene etc.; cationic lipids, e.g. DOTMA, DMRIE, di-C14-amidine, DOTIM, SAINT, DC-Chol, BGTC, CTAP, DOPC, DODAP, DOPE: Dioleyl phosphatidylethanol-amine, DOSPA, DODAB, DOIC, DMEPC, DOGS, DIMRI, DOTAP, DC-6-14, CLIP1, CLIP6, CLIP9, oligofectamine; or cationic or polycationic polymers, e.g. modified polyaminoacids, such as beta-aminoacid-polymers or reversed polyamides, etc., modified polyethylenes, such as PVP etc., modified acrylates, such as pDMAEMA etc., modified amidoamines such as pAMAM etc., modified polybetaaminoester (PBAE), such as diamine end modified 1,4 butanediol diacrylate-co-5-amino-1-pentanol polymers, etc., dendrimers, such as polypropylamine dendrimers or pAMAM based dendrimers, etc., polyimine(s), such as PEI, poly(propyleneimine), etc., polyallylamine, sugar backbone based polymers, such as cyclodextrin based polymers, dextran based polymers, etc., silan backbone based polymers, such as PMOXA-PDMS copolymers, etc., blockpolymers consisting of a combination of one or more cationic blocks (e.g. selected from a cationic polymer as mentioned above) and of one or more hydrophilic or hydrophobic blocks (e.g. polyethyleneglycole); etc.

In this context it is particularly preferred that the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed or at least partially complexed with a cationic or polycationic compound and/or a polymeric carrier, preferably cationic proteins or peptides. In this context, the disclosure of WO2010/037539 and WO2012/113513 is incorporated herewith by reference. Partially means that only a part of the nucleic acid is complexed with a cationic compound and that the rest of the nucleic acid is in uncomplexed form (“free”).

In embodiments, the composition comprises at least one nucleic acid (e.g. DNA or RNA), preferably at least one RNA, complexed with one or more cationic or polycationic compounds, preferably protamine, and at least one free (non-complexed) nucleic acid.

In this context it is particularly preferred that the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed, or at least partially complexed with protamine. Preferably, the molar ratio of the nucleic acid, particularly the RNA of the protamine-complexed RNA to the free RNA may be selected from a molar ratio of about 0.001:1 to about 1:0.001, including a ratio of about 1:1. Suitably, the complexed RNA is complexed with protamine by addition of protamine-trehalose solution to the RNA sample at a RNA:protamine weight to weight ratio (w/w) of 2:1.

Further preferred cationic or polycationic proteins or peptides that may be used for complexation can be derived from formula (Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x of the patent application WO2009/030481 or WO2011/026641, the disclosure of WO2009/030481 or WO2011/026641 relating thereto incorporated herewith by reference.

In preferred embodiments, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed, or at least partially complexed, with at least one cationic or polycationic proteins or peptides preferably selected from SEQ ID NOs: 269 to 273, or any combinations thereof.

According to various embodiments, the composition of the present invention comprises at least one nucleic acid (e.g. DNA or RNA), preferably at least one RNA as defined in the context of the first aspect, and a polymeric carrier.

The term “polymeric carrier” as used herein will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a compound that facilitates transport and/or complexation of another compound (e.g. cargo nucleic acid). A polymeric carrier is typically a carrier that is formed of a polymer. A polymeric carrier may be associated to its cargo (e.g. DNA, or RNA) by covalent or non-covalent interaction. A polymer may be based on different subunits, such as a copolymer.

Suitable polymeric carriers in that context may include, for example, polyacrylates, polyalkycyanoacrylates, polylactide, polylactide-polyglycolide copolymers, polycaprolactones, dextran, albumin, gelatin, alginate, collagen, chitosan, cyclodextrins, protamine, PEGylated protamine, PEGylated PLL and polyethylenimine (PEI), dithiobis(succinimidylpropionate) (DSP), Dimethyl-3,3′-dithiobispropionimidate (DTBP), poly(ethylene imine) biscarbamate (PEIC), poly(L-lysine) (PLL), histidine modified PLL, poly(N-vinylpyrrolidone) (PVP), poly(propylenimine (PPI), poly(amidoamine) (PAMAM), poly(amido ethylenimine) (SS-PAEI), triehtylenetetramine (TETA), poly((3-aminoester), poly(4-hydroxy-L-proine ester) (PHP), poly(allylamine), poly(a[4-aminobutyl]-L-glycolic acid (PAGA), Poly(D,L-lactic-co-glycolid acid (PLGA), Poly(N-ethyl-4-vinylpyridinium bromide), poly(phosphazene)s (PPZ), poly(phosphoester)s (PPE), poly(phosphoramidate)s (PPA), poly(N-2-hydroxypropylmethacrylamide) (pHPMA), poly(2-(dimethylamino)ethyl methacrylate) (pDMAEMA), poly(2-aminoethyl propylene phosphate) PPE_EA), galactosylated chitosan, N-dodecylated chitosan, histone, collagen and dextran-spermine. In one embodiment, the polymer may be an inert polymer such as, but not limited to, PEG. In one embodiment, the polymer may be a cationic polymer such as, but not limited to, PEI, PLL, TETA, poly(allylamine), Poly(N-ethyl-4-vinylpyridinium bromide), pHPMA and pDMAEMA. In one embodiment, the polymer may be a biodegradable PEI such as, but not limited to, DSP, DTBP and PEIC. In one embodiment, the polymer may be biodegradable such as, but not limited to, histine modified PLL, SS-PAEI, poly((3-aminoester), PHP, PAGA, PLGA, PPZ, PPE, PPA and PPE-EA.

A suitable polymeric carrier may be a polymeric carrier formed by disulfide-crosslinked cationic compounds. The disulfide-crosslinked cationic compounds may be the same or different from each other. The polymeric carrier can also contain further components. The polymeric carrier used according to the present invention may comprise mixtures of cationic peptides, proteins or polymers and optionally further components as defined herein, which are crosslinked by disulfide bonds (via —SH groups).

In this context, polymeric carriers according to formula {(Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x(Cys)y} and formula Cys,{(Arg)l;(Lys)m;(His)n;(Orn)o;(Xaa)x}Cys2 of the patent application WO2012/013326 are preferred, the disclosure of WO2012/013326 relating thereto incorporated herewith by reference.

In embodiments, the polymeric carrier used to complex the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA may be derived from a polymeric carrier molecule according formula (L-P¹-S-[S-P²-S]_n-S-P³-L) of the patent application WO2011/026641, the disclosure of WO2011/026641 relating thereto incorporated herewith by reference.

In embodiments, the polymeric carrier compound is formed by, or comprises or consists of the peptide elements CysArg12Cys (SEQ ID NO: 269) or CysArg12 (SEQ ID NO: 270) or TrpArg12Cys (SEQ ID NO: 271). In particularly preferred embodiments, the polymeric carrier compound consists of a (R₁₂C)-(R₁₂C) dimer, a (WR₁₂C)-(WR₁₂C) dimer, or a (CR₁₂)-(CR₁₂C)-(CR₁₂) trimer, wherein the individual peptide elements in the dimer (e.g. (WR12C)), or the trimer (e.g. (CR12)), are connected via —SH groups.

In a preferred embodiment of the second aspect, at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed or associated with a polyethylene glycol/peptide polymer comprising HO-PEG5000-S-(S-CHHHHHHRRRRHHHHHHC-S-)7-S-PEG5000-OH (SEQ ID NO: 272 as peptide monomer), HO-PEG5000-S-(S-CHHHHHHRRRRHHHHHHC-S-)4-S-PEG5000-OH (SEQ ID NO: 272 as peptide monomer), HO-PEG5000-S-(S-CGHHHHHRRRRHHHHHGC-S-)7-S-PEG5000-OH (SEQ ID NO: 273 as peptide monomer) and/or a polyethylene glycol/peptide polymer comprising HO-PEG5000-S-(S-CGHHHHHRRRRHHHHHGC-S-)4-S-PEG5000-OH (SEQ ID NO: 273 of the peptide monomer).

In other embodiments, the composition comprises at least one nucleic acid (e.g. DNA or RNA), wherein the at least one nucleic acid, preferably the at least one RNA is complexed or associated with polymeric carriers and, optionally, with at least one lipid component as described in WO2017/212008A1, WO2017/212006A1, WO2017/212007A1, and WO2017/212009A1. In this context, the disclosures of WO2017/212008A1, WO2017/212006A1, WO2017/212007A1, and WO2017/212009A1 are herewith incorporated by reference.

In a particularly preferred embodiment, the polymeric carrier (of the first and/or second component) is a peptide polymer, preferably a polyethylene glycol/peptide polymer as defined above, and a lipid component, preferably a lipidoid component.

A lipidoid (or lipidoit) is a lipid-like compound, i.e. an amphiphilic compound with lipid-like physical properties. The lipidoid is preferably a compound, which comprises two or more cationic nitrogen atoms and at least two lipophilic tails. In contrast to many conventional cationic lipids, the lipidoid may be free of a hydrolysable linking group, in particular linking groups comprising hydrolysable ester, amide or carbamate groups. The cationic nitrogen atoms of the lipidoid may be cationisable or permanently cationic, or both types of cationic nitrogens may be present in the compound. In the context of the present invention, the term lipid is considered to also encompass lipidoids.

In some embodiments of the inventions, the lipidoid may comprise a PEG moiety.

In preferred embodiments, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed or associated with a polymeric carrier, preferably with a polyethylene glycol/peptide polymer as defined above, and a lipidoid component.

Suitably, the lipidoid is cationic, which means that it is cationisable or permanently cationic. In one embodiment, the lipidoid is cationisable, i.e. it comprises one or more cationisable nitrogen atoms, but no permanently cationic nitrogen atoms. In another embodiment, at least one of the cationic nitrogen atoms of the lipidoid is permanently cationic. Optionally, the lipidoid comprises two permanently cationic nitrogen atoms, three permanently cationic nitrogen atoms, or even four or more permanently cationic nitrogen atoms.

In a preferred embodiment, the lipidoid component may be any one selected from the lipidoids of the lipidoids provided in the table of page 50-54 of published PCT patent application WO2017/212009A1, the specific lipidoids provided in said table, and the specific disclosure relating thereto herewith incorporated by reference.

In preferred embodiments, the lipidoid component may be any one selected from 3-C12-OH, 3-C12-OH-cat, 3-C12-amide, 3-C12-amide monomethyl, 3-C12-amide dimethyl, RevPEG(10)-3-C12-OH, RevPEG(10)-DLin-pAbenzoic, 3C12amide-TMA cat., 3C12amide-DMA, 3C12amide-NH2, 3C12amide-OH, 3C12Ester-OH, 3C12 Ester-amin, 3C12Ester-DMA, 2C12Amid-DMA, 3C12-lin-amid-DMA, 2C12-sperm-amid-DMA, or 3C12-sperm-amid-DMA (see table of published PCT patent application WO2017/212009A1 (pages 50-54)). Particularly preferred are 3-C12-OH or 3-C12-OH-cat.

In preferred embodiments, the polyethylene glycol/peptide polymer comprising a lipidoid as specified above (e.g. 3-C12-OH or 3-C12-OH-cat), is used to complex the at least one nucleic acid to form complexes having an N/P ratio from about 0.1 to about 20, or from about 0.2 to about 15, or from about 2 to about 15, or from about 2 to about 12, wherein the N/P ratio is defined as the mole ratio of the nitrogen atoms of the basic groups of the cationic peptide or polymer to the phosphate groups of the nucleic acid. In that context, the disclosure of published PCT patent application WO2017/212009A1, in particular claims 1 to 10 of WO2017/212009A1, and the specific disclosure relating thereto is herewith incorporated by reference.

Further suitable lipidoids may be derived from published PCT patent application WO2010/053572. In particular, lipidoids derivable from claims 1 to 297 of published PCT patent application WO2010/053572 may be used in the context of the invention, e.g. incorporated into the peptide polymer as described herein, or e.g. incorporated into the lipid nanoparticle (as described below). Accordingly, claims 1 to 297 of published PCT patent application WO2010/053572, and the specific disclosure relating thereto, is herewith incorporated by reference.

Encapsulation/Complexation in LNPs:

In preferred embodiments of the second aspect, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA, and optionally the at least one further nucleic acid, is complexed, encapsulated, partially encapsulated, or associated with one or more lipids (e.g. cationic lipids and/or neutral lipids), thereby forming lipid-based carriers such as liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes. The liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes—incorporated nucleic acid (e.g. DNA or RNA) may be completely or partially located in the interior space of the liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes, within the lipid layer/membrane, or associated with the exterior surface of the lipid layer/membrane. The incorporation of a nucleic acid into liposomes/LNPs is also referred to herein as “encapsulation” wherein the nucleic acid, e.g. the RNA is entirely contained within the interior space of the liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes. The purpose of incorporating nucleic acid into liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes is to protect the nucleic acid, preferably RNA from an environment which may contain enzymes or chemicals or conditions that degrade nucleic acid and/or systems or receptors that cause the rapid excretion of the nucleic acid. Moreover, incorporating nucleic acid, preferably RNA into liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes may promote the uptake of the nucleic acid, and hence, may enhance the therapeutic effect of the nucleic acid, e.g. the RNA encoding antigenic SARS-CoV-2 (nCoV-2019) proteins. Accordingly, incorporating a nucleic acid, e.g. RNA or DNA, into liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes may be particularly suitable for a coronavirus vaccine (e.g. a SARS-CoV-2 vaccine), e.g. for intramuscular and/or intradermal administration.

In this context, the terms “complexed” or “associated” refer to the essentially stable combination of nucleic acid with one or more lipids into larger complexes or assemblies without covalent binding.

The term “lipid nanoparticle”, also referred to as “LNP”, is not restricted to any particular morphology, and include any morphology generated when a cationic lipid and optionally one or more further lipids are combined, e.g. in an aqueous environment and/or in the presence of a nucleic acid, e.g. an RNA. For example, a liposome, a lipid complex, a lipoplex and the like are within the scope of a lipid nanoparticle (LNP).

Liposomes, lipid nanoparticles (LNPs), lipoplexes, and/or nanoliposomes can be of different sizes such as, but not limited to, a multilamellar vesicle (MLV) which may be hundreds of nanometers in diameter and may contain a series of concentric bilayers separated by narrow aqueous compartments, a small unicellular vesicle (SUV) which may be smaller than 50 nm in diameter, and a large unilamellar vesicle (LUV) which may be between 50 nm and 500 nm in diameter.

LNPs of the invention are suitably characterized as microscopic vesicles having an interior aqua space sequestered from an outer medium by a membrane of one or more bilayers. Bilayer membranes of LNPs are typically formed by amphiphilic molecules, such as lipids of synthetic or natural origin that comprise spatially separated hydrophilic and hydrophobic domains. Bilayer membranes of the liposomes can also be formed by amphophilic polymers and surfactants (e.g., polymerosomes, niosomes, etc.). In the context of the present invention, an LNP typically serves to transport the at least one nucleic acid, preferably the at least one RNA to a target tissue.

Accordingly, in preferred embodiments of the second aspect, the at least one nucleic acid, preferably the at least one RNA is complexed with one or more lipids thereby forming lipid nanoparticles (LNP). Preferably, said LNP is particularly suitable for intramuscular and/or intradermal administration. LNPs typically comprise a cationic lipid and one or more excipients selected from neutral lipids, charged lipids, steroids and polymer conjugated lipids (e.g. PEGylated lipid). The nucleic acid (e.g. RNA, DNA) may be encapsulated in the lipid portion of the LNP or an aqueous space enveloped by some or the entire lipid portion of the LNP. The nucleic acid (e.g. RNA, DNA) or a portion thereof may also be associated and complexed with the LNP. An LNP may comprise any lipid capable of forming a particle to which the nucleic acids are attached, or in which the one or more nucleic acids are encapsulated. Preferably, the LNP comprising nucleic acids comprises one or more cationic lipids, and one or more stabilizing lipids. Stabilizing lipids include neutral lipids and PEGylated lipids.

Preferably, the LNP comprises

• 
  
  
  
  • (i) at least one cationic lipid;
  
  
  • (ii) at least one neutral lipid;
  
  
  • (iii) at least one steroid or steroid analogue, preferably cholesterol; and
  
  
  • (iv) at least one polymer conjugated lipid, preferably a PEG-lipid;
  
  
  • wherein (i) to (iv) are in a molar ratio of about 20-60% cationic lipid, 5-25% neutral lipid, 25-55% sterol, and 0.5-15% polymer conjugated lipid.
  
  
  
  

The cationic lipid of an LNP may be cationisable, i.e. it becomes protonated as the pH is lowered below the pK of the ionizable group of the lipid, but is progressively more neutral at higher pH values. At pH values below the pK, the lipid is then able to associate with negatively charged nucleic acids. In certain embodiments, the cationic lipid comprises a zwitterionic lipid that assumes a positive charge on pH decrease.

Such lipids include, but are not limited to, DSDMA, N,N-dioleyl-N,N-dimethylammonium chloride (DODAC), N,N-distearyl-N,N-dimethylammonium bromide (DDAB), 1,2-dioleoyltrimethyl ammonium propane chloride (DOTAP) (also known as N-(2,3-dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride and 1,2-Dioleyloxy-3-trimethylaminopropane chloride salt), N-(1-(2,3-dioleyloxy)propyl)-N,N,N-trimethylammonium chloride (DOTMA), N,N-dimethyl-2,3-dioleyloxy)propylamine (DODMA), ckk-E12, ckk, 1,2-DiLinoleyloxy-N,N-dimethylaminopropane (DLinDMA), 1,2-Dilinolenyloxy-N, N-dimethylaminopropane (DLenDMA), 1,2-di-y-linolenyloxy-N,N-dimethylaminopropane (y-DLenDMA), 98N12-5, 1,2-Dilinoleylcarbamoyloxy-3-dimethylaminopropane (DLin-C-DAP), 1,2-Dilinoleyoxy-3-(dimethylamino)acetoxypropane (DLin-DAC), 1,2-Dilinoleyoxy-3-morpholinopropane (DLin-MA), 1,2-Dilinoleoyl-3-dimethylaminopropane (DLinDAP), 1,2-Dilinoleylthio-3-dimethylaminopropane (DLin-S-DMA), 1-Linoleoyl-2-linoleyloxy-3-dimethylaminopropane (DLin-2-DMAP), 1,2-Dilinoleyloxy-3-trimethylaminopropane chloride salt (DLin-TMA.Cl), ICE (Imidazol-based), HGT5000, HGT5001, DMDMA, CLinDMA, CpLinDMA, DMOBA, DOcarbDAP, DLincarbDAP, DLinCDAP, KLin-K-DMA, DLin-K-XTC2-DMA, XTC (2,2-Dilinoleyl-4-dimethylaminoethyl-[1,3]-dioxolane) HGT4003, 1,2-Dilinoleoyl-3-trimethylaminopropane chloride salt (DLin-TAP.Cl), 1,2-Dilinoleyloxy-3-(N-methylpiperazino)propane (DLin-MPZ), or 3-(N,N-Dilinoleylamino)-1,2-propanediol (DLinAP), 3-(N,N-Dioleylamino)-1,2-propanedio (DOAP), 1,2-Dilinoleyloxo-3-(2-N,N-dimethylamino)ethoxypropane (DLin-EG-DMA), 2,2-Dilinoleyl-4-dimethylaminomethyl-[1,3]-dioxolane (DLin-K-DMA) or analogs thereof, (3aR,5s,6aS)-N,N-dimethyl-2,2-di((9Z,12Z)-octadeca-9,12-dienyl)tetrahydro-3aH-cyclopenta[d][1,3]dioxol-5-amine, (6Z,9Z,28Z,31Z)-heptatriaconta-6,9,28,31-tetraen-19-yl-4-(dimethylamino)butanoate (MC3), ALNY-100 ((3aR,5s,6aS)-N,N-dimethyl-2,2-di((9Z,12Z)-octadeca-9,12-dienyl)tetrahydro-3aH-cyclopenta[d][1,3]dioxol-5-amine)), 1,1′-(2-(4-(2-((2-(bis(2-hydroxydodecyl)amino)ethyl)(2-hydroxydodecyl)amino)ethyl)piperazin-1-yl)ethylazanediyl)didodecan-2-ol (C12-200), 2,2-dilinoleyl-4-(2-dimethylaminoethyl)[1,3]-dioxolane (DLin-K-C2-DMA), 2,2-dilinoleyl-4-dimethylaminomethyl-[1,3]-dioxolane (DLin-K-DMA), NC98-5 (4,7, 13-tris(3-oxo-3-(undecylamino)propyl)-N1,N 16-diundecyl-4,7, 10,13-tetraazahexadecane-1,16-diamide), (6Z,9Z,28Z,31Z)-heptatriaconta-6,9,28,31-tetraen-19-yl 4-(dimethylamino) butanoate (DLin-M-C3-DMA), 3-((6Z,9Z,28Z,31Z)-heptatriaconta-6,9,28,31-tetraen-19-yloxy)-N,N-dimethylpropan-1-amine (MC3 Ether), 4-((6Z,9Z,28Z,31Z)-heptatriaconta-6,9,28,31-tetraen-19-yloxy)-N,N-dimethylbutan-1-amine (MC4 Ether), LIPOFECTIN® (commercially available cationic liposomes comprising DOTMA and 1,2-dioleoyl-sn-3phosphoethanolamine (DOPE), from GIBCO/BRL, Grand Island, N.Y.); LIPOFECTAMINE® (commercially available cationic liposomes comprising N-(1-(2,3dioleyloxy)propyl)-N-(2-(sperminecarboxamido)ethyl)-N,N-dimethylammonium trifluoroacetate (DOSPA) and (DOPE), from GIBCO/BRL); and TRANSFECTAM® (commercially available cationic lipids comprising dioctadecylamidoglycyl carboxyspermine (DOGS) in ethanol from Promega Corp., Madison, Wis.) or any combination of any of the foregoing. Further suitable cationic lipids for use in the compositions and methods of the invention include those described in international patent publications WO2010/053572 (and particularly, CI 2-200 described at paragraph [00225]) and WO2012/170930, both of which are incorporated herein by reference, HGT4003, HGT5000, HGTS001, HGT5001, HGT5002 (see US20150140070A1).

In embodiments, the cationic lipid may be an amino lipid.

Representative amino lipids include, but are not limited to, 1,2-dilinoleyoxy-3-(dimethylamino)acetoxypropane (DLin-DAC), 1,2-dilinoleyoxy-3morpholinopropane (DLin-MA), 1,2-dilinoleoyl-3-dimethylaminopropane (DLinDAP), 1,2-dilinoleylthio-3-dimethylaminopropane (DLin-S-DMA), 1-linoleoyl-2-linoleyloxy-3dimethylaminopropane (DLin-2-DMAP), 1,2-dilinoleyloxy-3-trimethylaminopropane chloride salt (DLin-TMA.Cl), 1,2-dilinoleoyl-3-trimethylaminopropane chloride salt (DLin-TAP.Cl), 1,2-dilinoleyloxy-3-(N-methylpiperazino)propane (DLin-MPZ), 3-(N,Ndilinoleylamino)-1,2-propanediol (DLinAP), 3-(N,N-dioleylamino)-1,2-propanediol (DOAP), 1,2-dilinoleyloxo-3-(2-N,N-dimethylamino)ethoxypropane (DLin-EG-DMA), and 2,2-dilinoleyl-4-dimethylaminomethyl[1,3]-dioxolane (DLin-K-DMA), 2,2-dilinoleyl-4-(2-dimethylaminoethyl)[1,3]-dioxolane (DLin-KC2-DMA); dilinoleyl-methyl-4-dimethylaminobutyrate (DLin-MC3-DMA); MC3 (US20100324120).

In embodiments, the cationic lipid may an aminoalcohol lipidoid.

Aminoalcohol lipidoids which may be used in the present invention may be prepared by the methods described in U.S. Pat. No. 8,450,298, herein incorporated by reference in its entirety. Suitable (ionizable) lipids can also be the compounds as disclosed in Tables 1, 2 and 3 and as defined in claims 1-24 of WO2017/075531A1, hereby incorporated by reference.

In another embodiment, suitable lipids can also be the compounds as disclosed in WO2015/074085A1 (i.e. ATX-001 to ATX-032 or the compounds as specified in claims 1-26), U.S. Appl. No. 61/905,724 and Ser. No. 15/614,499 or U.S. Pat. Nos. 9,593,077 and 9,567,296 hereby incorporated by reference in their entirety.

In other embodiments, suitable cationic lipids can also be the compounds as disclosed in WO2017/117530A1 (i.e. lipids 13, 14, 15, 16, 17, 18, 19, 20, or the compounds as specified in the claims), hereby incorporated by reference in its entirety.

In preferred embodiments, ionizable or cationic lipids may also be selected from the lipids disclosed in WO2018/078053A1 (i.e. lipids derived from formula I, II, and III of WO2018/078053A1, or lipids as specified in claims 1 to 12 of WO2018/078053A1), the disclosure of WO2018/078053A1 hereby incorporated by reference in its entirety. In that context, lipids disclosed in Table 7 of WO2018/078053A1 (e.g. lipids derived from formula I-1 to I-41) and lipids disclosed in Table 8 of WO2018/078053A1 (e.g. lipids derived from formula II-1 to II-36) may be suitably used in the context of the invention. Accordingly, formula I-1 to formula I-41 and formula II-1 to formula II-36 of WO2018/078053A1, and the specific disclosure relating thereto, are herewith incorporated by reference.

In preferred embodiments, cationic lipids may be derived from formula III of published PCT patent application WO2018/078053A1. Accordingly, formula III of WO2018/078053A1, and the specific disclosure relating thereto, are herewith incorporated by reference.

In particularly preferred embodiments, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA of the composition is complexed with one or more lipids thereby forming LNPs, wherein the cationic lipid of the LNP is selected from structures III-1 to III-36 of Table 9 of published PCT patent application WO2018/078053A1. Accordingly, formula III-1 to III-36 of WO2018/078053A1, and the specific disclosure relating thereto, are herewith incorporated by reference.

In particularly preferred embodiment of the second aspect, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed with one or more lipids thereby forming LNPs, wherein the LNPs comprises a cationic lipid according to formula III-3:

The lipid of formula III-3 as suitably used herein has the chemical term ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), also referred to as ALC-0315.

In certain embodiments, the cationic lipid as defined herein, more preferably cationic lipid compound 111-3, is present in the LNP in an amount from about 30 to about 95 mole percent, relative to the total lipid content of the LNP. If more than one cationic lipid is incorporated within the LNP, such percentages apply to the combined cationic lipids. In embodiments, the cationic lipid is present in the LNP in an amount from about 30 to about 70 mole percent. In one embodiment, the cationic lipid is present in the LNP in an amount from about 40 to about 60 mole percent, such as about 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59 or 60 mole percent, respectively. In embodiments, the cationic lipid is present in the LNP in an amount from about 47 to about 48 mole percent, such as about 47.0, 47.1, 47.2, 47.3, 47.4, 47.5, 47.6, 47.7, 47.8, 47.9, 50.0 mole percent, respectively, wherein 47.7 mole percent are particularly preferred.

In some embodiments, the cationic lipid is present in a ratio of from about 20 mol % to about 70 or 75 mol % or from about 45 to about 65 mol % or about 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, or about 70 mol % of the total lipid present in the LNP. In further embodiments, the LNPs comprise from about 25% to about 75% on a molar basis of cationic lipid, e.g., from about 20 to about 70%, from about 35 to about 65%, from about 45 to about 65%, about 60%, about 57.5%, about 57.1%, about 50% or about 40% on a molar basis (based upon 100% total moles of lipid in the lipid nanoparticle). In some embodiments, the ratio of cationic lipid to nucleic acid (e.g. coding RNA or DNA) is from about 3 to about 15, such as from about 5 to about 13 or from about 7 to about 11.

Other suitable (cationic or ionizable) lipids are disclosed in WO2009/086558, WO2009/127060, WO2010/048536, WO2010/054406, WO2010/088537, WO2010/129709, WO2011/153493, WO 2013/063468, US2011/0256175, US2012/0128760, US2012/0027803, U.S. Pat. No. 8,158,601, WO2016/118724, WO2016/118725, WO2017/070613, WO2017/070620, WO2017/099823, WO2012/040184, WO2011/153120, WO2011/149733, WO2011/090965, WO2011/043913, WO2011/022460, WO2012/061259, WO2012/054365, WO2012/044638, WO2010/080724, WO2010/21865, WO2008/103276, WO2013/086373, WO2013/086354, U.S. Pat. Nos. 7,893,302, 7,404,969, 8,283,333, 8,466,122 and 8,569,256 and US Patent Publication No. US2010/0036115, US2012/0202871, US2013/0064894, US2013/0129785, US2013/0150625, US2013/0178541, US2013/0225836, US2014/0039032 and WO2017/112865. In that context, the disclosures of WO2009/086558, WO2009/127060, WO2010/048536, WO2010/054406, WO2010/088537, WO2010/129709, WO2011/153493, WO 2013/063468, US2011/0256175, US2012/0128760, US2012/0027803, U.S. Pat. No. 8,158,601, WO2016/118724, WO2016/118725, WO2017/070613, WO2017/070620, WO2017/099823, WO2012/040184, WO2011/153120, WO2011/149733, WO2011/090965, WO2011/043913, WO2011/022460, WO2012/061259, WO2012/054365, WO2012/044638, WO2010/080724, WO2010/21865, WO2008/103276, WO2013/086373, WO2013/086354, U.S. Pat. Nos. 7,893,302, 7,404,969, 8,283,333, 8,466,122 and 8,569,256 and US Patent Publication No. US2010/0036115, US2012/0202871, US2013/0064894, US2013/0129785, US2013/0150625, US2013/0178541, US2013/0225836 and US2014/0039032 and WO2017/112865 specifically relating to (cationic) lipids suitable for LNPs are incorporated herewith by reference.

In embodiments, amino or cationic lipids as defined herein have at least one protonatable or deprotonatable group, such that the lipid is positively charged at a pH at or below physiological pH (e.g. pH 7.4), and neutral at a second pH, preferably at or above physiological pH. It will, of course, be understood that the addition or removal of protons as a function of pH is an equilibrium process, and that the reference to a charged or a neutral lipid refers to the nature of the predominant species and does not require that all of lipids have to be present in the charged or neutral form. Lipids having more than one protonatable or deprotonatable group, or which are zwitterionic, are not excluded and may likewise suitable in the context of the present invention. In some embodiments, the protonatable lipids have a pKa of the protonatable group in the range of about 4 to about 11, e.g., a pKa of about 5 to about 7.

LNPs can comprise two or more (different) cationic lipids as defined herein. Cationic lipids may be selected to contribute to different advantageous properties. For example, cationic lipids that differ in properties such as amine pKa, chemical stability, half-life in circulation, half-life in tissue, net accumulation in tissue, or toxicity can be used in the LNP. In particular, the cationic lipids can be chosen so that the properties of the mixed-LNP are more desirable than the properties of a single-LNP of individual lipids.

The amount of the permanently cationic lipid or lipidoid may be selected taking the amount of the nucleic acid cargo into account. In one embodiment, these amounts are selected such as to result in an N/P ratio of the nanoparticle(s) or of the composition in the range from about 0.1 to about 20. In this context, the N/P ratio is defined as the mole ratio of the nitrogen atoms (“N”) of the basic nitrogen-containing groups of the lipid or lipidoid to the phosphate groups (“P”) of the nucleic acid which is used as cargo. The N/P ratio may be calculated on the basis that, for example, 1 ug RNA typically contains about 3nmol phosphate residues, provided that the RNA exhibits a statistical distribution of bases. The “N”-value of the lipid or lipidoid may be calculated on the basis of its molecular weight and the relative content of permanently cationic and—if present—cationisable groups.

In vivo characteristics and behavior of LNPs can be modified by addition of a hydrophilic polymer coating, e.g. polyethylene glycol (PEG), to the LNP surface to confer steric stabilization. Furthermore, LNPs can be used for specific targeting by attaching ligands (e.g. antibodies, peptides, and carbohydrates) to its surface or to the terminal end of the attached PEG chains (e.g. via PEGylated lipids or PEGylated cholesterol).

In some embodiments, the LNPs comprise a polymer conjugated lipid. The term “polymer conjugated lipid” refers to a molecule comprising both a lipid portion and a polymer portion. An example of a polymer conjugated lipid is a PEGylated lipid. The term “PEGylated lipid” refers to a molecule comprising both a lipid portion and a polyethylene glycol portion. PEGylated lipids are known in the art and include 1-(monomethoxy-polyethyleneglycol)-2,3-dimyristoylglycerol (PEG-s-DMG) and the like.

A polymer conjugated lipid as defined herein, e.g. a PEG-lipid, may serve as an aggregation reducing lipid.

In certain embodiments, the LNP comprises a stabilizing-lipid which is a polyethylene glycol-lipid (PEGylated lipid). Suitable polyethylene glycol-lipids include PEG-modified phosphatidylethanolamine, PEG-modified phosphatidic acid, PEG-modified ceramides (e.g. PEG-CerC14 or PEG-CerC20), PEG-modified dialkylamines, PEG-modified diacylglycerols, PEG-modified dialkylglycerols. Representative polyethylene glycol-lipids include PEG-c-DOMG, PEG-c-DMA, and PEG-s-DMG. In one embodiment, the polyethylene glycol-lipid is N-[(methoxy poly(ethylene glycol)2000)carbamyl]-1,2-dimyristyloxlpropyl-3-amine (PEG-c-DMA). In a preferred embodiment, the polyethylene glycol-lipid is PEG-2000-DMG. In one embodiment, the polyethylene glycol-lipid is PEG-c-DOMG). In other embodiments, the LNPs comprise a PEGylated diacylglycerol (PEG-DAG) such as 1-(monomethoxy-polyethyleneglycol)-2,3-dimyristoylglycerol (PEG-DMG), a PEGylated phosphatidylethanoloamine (PEG-PE), a PEG succinate diacylglycerol (PEG-S-DAG) such as 4-O-(2′,3′-di(tetradecanoyloxy)propyl-1-O-(ω-methoxy(polyethoxy)ethyl)butanedioate (PEG-S-DMG), a PEGylated ceramide (PEG-cer), or a PEG dialkoxypropylcarbamate such as ω-methoxy(polyethoxy)ethyl-N-(2,3di(tetradecanoxy)propyl)carbamate or 2,3-di(tetradecanoxy)propyl-N-(ω-methoxy(polyethoxy)ethyl)carbamate.

In preferred embodiments, the PEGylated lipid is preferably derived from formula (IV) of published PCT patent application WO2018/078053A1. Accordingly, PEGylated lipids derived from formula (IV) of published PCT patent application WO2018/078053A1, and the respective disclosure relating thereto, are herewith incorporated by reference.

In a particularly preferred embodiments, the at least one nucleic acid (e.g. RNA or DNA) of the composition is complexed with one or more lipids thereby forming LNPs, wherein the LNP comprises a PEGylated lipid, wherein the PEG lipid is preferably derived from formula (IVa) of published PCT patent application WO2018/078053A1. Accordingly, PEGylated lipid derived from formula (IVa) of published PCT patent application WO2018/078053A1, and the respective disclosure relating thereto, is herewith incorporated by reference.

In a particularly preferred embodiment, the at least one nucleic acid, preferably the at least one RNA is complexed with one or more lipids thereby forming lipid nanoparticles (LNP), wherein the LNP comprises a PEGylated lipid/PEG lipid. Preferably, said PEG lipid is of formula (IVa):

wherein n has a mean value ranging from 30 to 60, such as about 30±2, 32±2, 34±2, 36±2, 38±2, 40±2, 42±2, 44±2, 46±2, 48±2, 50±2, 52±2, 54±2, 56±2, 58±2, or 60±2. In a most preferred embodiment n is about 49. In further preferred aspects said PEG lipid is of formula (IVa) wherein n is an integer selected such that the average molecular weight of the PEG lipid is about 2000 g/mol to about 3000 g/mol or about 2300 g/mol to about 2700 g/mol, even more preferably about 2500 g/mol.

The lipid of formula IVa as suitably used herein has the chemical term 2[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, also referred to as ALC-0159.

Further examples of PEG-lipids suitable in that context are provided in US2015/0376115A1 and WO2015/199952, each of which is incorporated by reference in its entirety.

In some embodiments, LNPs include less than about 3, 2, or 1 mole percent of PEG or PEG-modified lipid, based on the total moles of lipid in the LNP. In further embodiments, LNPs comprise from about 0.1% to about 20% of the PEG-modified lipid on a molar basis, e.g., about 0.5 to about 10%, about 0.5 to about 5%, about 10%, about 5%, about 3.5%, about 3%, about 2.5%, about 2%, about 1.5%, about 1%, about 0.5%, or about 0.3% on a molar basis (based on 100% total moles of lipids in the LNP). In preferred embodiments, LNPs comprise from about 1.0% to about 2.0% of the PEG-modified lipid on a molar basis, e.g., about 1.2 to about 1.9%, about 1.2 to about 1.8%, about 1.3 to about 1.8%, about 1.4 to about 1.8%, about 1.5 to about 1.8%, about 1.6 to about 1.8%, in particular about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 1.8%, about 1.9%, most preferably 1.7% (based on 100% total moles of lipids in the LNP). In various embodiments, the molar ratio of the cationic lipid to the PEGylated lipid ranges from about 100:1 to about 25:1.

In preferred embodiments, the LNP comprises one or more additional lipids, which stabilize the formation of particles during their formation or during the manufacturing process (e.g. neutral lipid and/or one or more steroid or steroid analogue).

In preferred embodiments of the second aspect, the at least one nucleic acid, preferably the at least one RNA is complexed with one or more lipids thereby forming lipid nanoparticles (LNP), wherein the LNP comprises one or more neutral lipid and/or one or more steroid or steroid analogue.

Suitable stabilizing lipids include neutral lipids and anionic lipids. The term “neutral lipid” refers to any one of a number of lipid species that exist in either an uncharged or neutral zwitterionic form at physiological pH. Representative neutral lipids include diacylphosphatidylcholines, diacylphosphatidylethanolamines, ceramides, sphingomyelins, dihydro sphingomyelins, cephalins, and cerebrosides.

In embodiments of the second aspect, the LNP comprises one or more neutral lipids, wherein the neutral lipid is selected from the group comprising distearoylphosphatidylcholine (DSPC), dioleoylphosphatidylcholine (DOPC), dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylglycerol (DOPG), dipalmitoylphosphatidylglycerol (DPPG), dioleoyl-phosphatidylethanolamine (DOPE), palmitoyloleoylphosphatidylcholine (POPC), palmitoyloleoyl-phosphatidylethanolamine (POPE) and dioleoyl-phosphatidylethanolamine 4-(N-maleimidomethyl)-cyclohexane-1carboxylate (DOPE-mal), dipalmitoyl phosphatidyl ethanolamine (DPPE), dimyristoylphosphoethanolamine (DMPE), distearoyl-phosphatidylethanolamine (DSPE), 16-O-monomethyl PE, 16-O-dimethyl PE, 18-1-trans PE, 1-stearioyl-2-oleoylphosphatidyethanol amine (SOPE), and 1,2-dielaidoyl-sn-glycero-3-phophoethanolamine (transDOPE), or mixtures thereof.

In some embodiments, the LNPs comprise a neutral lipid selected from DSPC, DPPC, DMPC, DOPC, POPC, DOPE and SM. In various embodiments, the molar ratio of the cationic lipid to the neutral lipid ranges from about 2:1 to about 8:1.

In preferred embodiments, the neutral lipid is 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC). The molar ratio of the cationic lipid to DSPC may be in the range from about 2:1 to about 8:1.

In preferred embodiments, the steroid is cholesterol. The molar ratio of the cationic lipid to cholesterol may be in the range from about 2:1 to about 1:1. In some embodiments, the cholesterol may be PEGylated.

The sterol can be about 10 mol % to about 60 mol % or about 25 mol % to about 40 mol % of the lipid particle. In one embodiment, the sterol is about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or about 60 mol % of the total lipid present in the lipid particle. In another embodiment, the LNPs include from about 5% to about 50% on a molar basis of the sterol, e.g., about 15% to about 45%, about 20% to about 40%, about 48%, about 40%, about 38.5%, about 35%, about 34.4%, about 31.5% or about 31% on a molar basis (based upon 100% total moles of lipid in the lipid nanoparticle).

Preferably, lipid nanoparticles (LNPs) comprise: (a) the at least one nucleic acid, preferably the at least one RNA of the first aspect, (b) a cationic lipid, (c) an aggregation reducing agent (such as polyethylene glycol (PEG) lipid or PEG-modified lipid), (d) optionally a non-cationic lipid (such as a neutral lipid), and (e) optionally, a sterol.

In some embodiments, the cationic lipids (as defined above), non-cationic lipids (as defined above), cholesterol (as defined above), and/or PEG-modified lipids (as defined above) may be combined at various relative molar ratios. For example, the ratio of cationic lipid to non-cationic lipid to cholesterol-based lipid to PEGylated lipid may be between about 30-60:20-35:20-30:1-15, or at a ratio of about 40:30:25:5, 50:25:20:5, 50:27:20:3, 40:30:20:10, 40:32:20:8, 40:32:25:3 or 40:33:25:2, or at a ratio of about 50:25:20:5, 50:20:25:5, 50:27:20:3 40:30:20:10, 40:30:25:5 or 40:32:20:8, 40:32:25:3 or 40:33:25:2, respectively.

In some embodiments, the LNPs comprise a lipid of formula (III), the at least one nucleic acid, preferably the at least one RNA as defined herein, a neutral lipid, a steroid and a PEGylated lipid. In preferred embodiments, the lipid of formula (III) is lipid compound III-3 (ALC-0315), the neutral lipid is DSPC, the steroid is cholesterol, and the PEGylated lipid is the compound of formula (IVa) (ALC-0159).

In a preferred embodiment of the second aspect, the LNP consists essentially of (i) at least one cationic lipid; (ii) a neutral lipid; (iii) a sterol, e.g., cholesterol; and (iv) a PEG-lipid, e.g. PEG-DMG or PEG-cDMA, in a molar ratio of about 20-60% cationic lipid:5-25% neutral lipid:25-55% sterol; 0.5-15% PEG-lipid.

In particularly preferred embodiments, the at least one nucleic acid, preferably the at least one RNA is complexed with one or more lipids thereby forming lipid nanoparticles (LNP), wherein the LNP comprises

• (i) at least one cationic lipid as defined herein, preferably a lipid of formula (III), more preferably lipid III-3 (ALC-0315);


• (ii) at least one neutral lipid as defined herein, preferably 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC);


• (iii) at least one steroid or steroid analogue as defined herein, preferably cholesterol; and


• (iv) at least one PEG-lipid as defined herein, e.g. PEG-DMG or PEG-cDMA, preferably a PEGylated lipid that is or is derived from formula (IVa) (ALC-0159).

In particularly preferred embodiments, the at least one nucleic acid, preferably the at least one RNA is complexed with one or more lipids thereby forming lipid nanoparticles (LNP), wherein the LNP comprises (i) to (iv) in a molar ratio of about 20-60% cationic lipid:5-25% neutral lipid:25-55% sterol; 0.5-15% PEG-lipid.

In one preferred embodiment, the lipid nanoparticle comprises: a cationic lipid with formula (III) and/or PEG lipid with formula (IV), optionally a neutral lipid, preferably 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and optionally a steroid, preferably cholesterol, wherein the molar ratio of the cationic lipid to DSPC is optionally in the range from about 2:1 to 8:1, wherein the molar ratio of the cationic lipid to cholesterol is optionally in the range from about 2:1 to 1:1.

In a particular preferred embodiment, the composition of the second aspect comprising the at least one nucleic acid, preferably the at least one RNA, comprises lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 (i.e. proportion (mol %) of cationic lipid (preferably lipid III-3 (ALC-0315)), DSPC, cholesterol and PEG-lipid (preferably PEG-lipid of formula (IVa) with n=49, even more preferably PEG-lipid of formula (IVa) with n=45 (ALC-0159)); solubilized in ethanol).

Most preferably, the composition of the second aspect comprises at least one nucleic acid, preferably RNA, which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 163 formulated in lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45 (ALC-0159)). In this preferred embodiment the nucleic acid, preferably mRNA is not chemically modified.

In another most preferred embodiment, the composition of the second aspect comprises at least one nucleic acid, preferably RNA, which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 149 formulated in lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45 (ALC-0159)). In this preferred embodiment the nucleic acid, preferably mRNA is not chemically modified.

In another most preferred embodiment, the composition of the second aspect comprises at least one nucleic acid, preferably RNA, which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 24837 formulated in lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45) (ALC-0159). In this preferred embodiment the nucleic acid, preferably mRNA is not chemically modified.

In a further preferred embodiment, the composition of the second aspect comprises at least one nucleic acid, preferably RNA, which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 23311, 23531, or 24851 formulated in lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45) (ALC-0159). In this preferred embodiment the nucleic acid, preferably mRNA is not chemically modified.

In a further preferred embodiment, the composition of the second aspect comprises at least one nucleic acid, preferably RNA, which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 23310, 23530, 23313, or 23533 formulated in lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45) (ALC-0159). In this preferred embodiment the nucleic acid, preferably mRNA is not chemically modified.

In embodiments where the composition is a multivalent composition as defined above, the nucleic acid species (e.g. DNA or RNA), preferably RNA species of the multivalent composition may be formulated separately, preferably formulated separately in liposomes or LNPs. Suitably, the RNA species of the multivalent composition are separately formulated in LNPs which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45). Nucleic acid species for multivalent compositions are preferably selected as defined above (see section “Multivalent compositions of the invention”)

In embodiments where the composition is a multivalent composition as defined above, the nucleic acid species (e.g. DNA or RNA), preferably RNA species of the multivalent composition may be co-formulated, preferably co-formulated in liposomes or LNPs. Suitably, the RNA species of the multivalent composition are co-formulated in LNPs which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45).

Nucleic acid species for multivalent compositions are preferably selected as defined above (see section “Multivalent compositions of the invention”)

The total amount of nucleic acid in the lipid nanoparticles may vary and is defined depending on the e.g. nucleic acid to total lipid w/w ratio. In one embodiment of the invention the nucleic acid, in particular the RNA to total lipid ratio is less than 0.06 w/w, preferably between 0.03 w/w and 0.04 w/w.

In some embodiments, the lipid nanoparticles (LNPs), which are composed of only three lipid components, namely imidazole cholesterol ester (ICE), 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), and 1,2-dimyristoyl-sn-glycerol, methoxypolyethylene glycol (DMG-PEG-2K).

In one embodiment, the lipid nanoparticle of the composition comprises a cationic lipid, a steroid; a neutral lipid; and a polymer conjugated lipid, preferably a pegylated lipid. Preferably, the polymer conjugated lipid is a pegylated lipid or PEG-lipid. In a specific embodiment, lipid nanoparticles comprise a cationic lipid resembled by the cationic lipid COATSOME® SS-EC (former name: SS-33/4PE-15; NOF Corporation, Tokyo, Japan), in accordance with the following formula

As described further below, those lipid nanoparticles are termed “GN01”.

Furthermore, in a specific embodiment, the GN01 lipid nanoparticles comprise a neutral lipid being resembled by the structure 1,2-diphytanoyl-sn-glycero-3-phosphoethanolamine (DPhyPE):

Furthermore, in a specific embodiment, the GN01 lipid nanoparticles comprise a polymer conjugated lipid, preferably a pegylated lipid, being 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol 2000 (DMG-PEG 2000) having the following structure:

As used in the art, “DMG-PEG 2000” is considered a mixture of 1,2-DMG PEG2000 and 1,3-DMG PEG2000 in ˜97:3 ratio.

Accordingly, GN01 lipid nanoparticles (GN01-LNPs) according to one of the preferred embodiments comprise a SS-EC cationic lipid, neutral lipid DPhyPE, cholesterol, and the polymer conjugated lipid (pegylated lipid) 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol (PEG-DMG).

In a preferred embodiment, the GN01 LNPs comprise:

(a) cationic lipid SS-EC (former name: SS-33/4PE-15; NOF Corporation, Tokyo, Japan) at an amount of 45-65 mol %;

(b) cholesterol at an amount of 25-45 mol %;

(c) DPhyPE at an amount of 8-12 mol %; and

(d) PEG-DMG 2000 at an amount of 1-3 mol %;

each amount being relative to the total molar amount of all lipidic excipients of the GN01 lipid nanoparticles.

In a further preferred embodiment, the GN01 lipid nanoparticles as described herein comprises 59 mol % cationic lipid, 10 mol % neutral lipid, 29.3 mol % steroid and 1.7 mol % polymer conjugated lipid, preferably pegylated lipid. In a most preferred embodiment, the GN01 lipid nanoparticles as described herein comprise 59 mol % cationic lipid SS-EC, 10 mol % DPhyPE, 29.3 mol % cholesterol and 1.7 mol % DMG-PEG 2000.

The amount of the cationic lipid relative to that of the nucleic acid in the GN01 lipid nanoparticle may also be expressed as a weight ratio (abbreviated f.e. “m/m”). For example, the GN01 lipid nanoparticles comprise the at least one nucleic acid, preferably the at least one RNA at an amount such as to achieve a lipid to RNA weight ratio in the range of about 20 to about 60, or about 10 to about 50. In other embodiments, the ratio of cationic lipid to nucleic acid or RNA is from about 3 to about 15, such as from about 5 to about 13, from about 4 to about 8 or from about 7 to about 11. In a very preferred embodiment of the present invention, the total lipid/RNA mass ratio is about 40 or 40, i.e. about 40 or 40 times mass excess to ensure RNA encapsulation. Another preferred RNA/lipid ratio is between about 1 and about 10, about 2 and about 5, about 2 and about 4, or preferably about 3.

Further, the amount of the cationic lipid may be selected taking the amount of the nucleic acid cargo such as the RNA compound into account. In one embodiment, the N/P ratio can be in the range of about 1 to about 50. In another embodiment, the range is about 1 to about 20, about 1 to about 10, about 1 to about 5. In one preferred embodiment, these amounts are selected such as to result in an N/P ratio of the GN01 lipid nanoparticles or of the composition in the range from about 10 to about 20. In a further very preferred embodiment, the N/P is 14 (i.e. 14 times mol excess of positive charge to ensure nucleic acid encapsulation).

In a preferred embodiment, GN01 lipid nanoparticles comprise 59 mol % cationic lipid COATSOME® SS-EC (former name: SS-33/4PE-15 as apparent from the examples section; NOF Corporation, Tokyo, Japan), 29.3 mol % cholesterol as steroid, 10 mol % DPhyPE as neutral lipid/phospholipid and 1.7 mol % DMG-PEG 2000 as polymer conjugated lipid. A further inventive advantage connected with the use of DPhyPE is the high capacity for fusogenicity due to its bulky tails, whereby it is able to fuse at a high level with endosomal lipids. For “GN01”, N/P (lipid to nucleic acid, e.g RNA mol ratio) preferably is 14 and total lipid/RNA mass ratio preferably is 40 (m/m).

In other embodiments, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed with one or more lipids thereby forming lipid nanoparticles (LNP), wherein the LNP comprises

• 
  
  
  
  • l at least one cationic lipid;
  
  
  • li at least one neutral lipid;
  
  
  • lii at least one steroid or steroid analogue; and
  
  
  • liii at least one PEG-lipid as defined herein,
  
  
  
  

wherein the cationic lipid is DLin-KC2-DMA (50 mol %) or DLin-MC3-DMA (50 mol %), the neutral lipid is DSPC (10 mol %), the PEG lipid is PEG-DOMG (1.5 mol %) and the structural lipid is cholesterol (38.5 mol %).

In other embodiments, the at least one nucleic acid (e.g. DNA or RNA), preferably the at least one RNA is complexed with one or more lipids thereby forming lipid nanoparticles (LNP), wherein the LNP comprises SS15/Chol/DOPE (or DOPC)/DSG-5000 at mol % 50/38.5/10/1.5.

In other embodiments, the nucleic acid of the invention may be formulated in liposomes, e.g. in liposomes as described in WO2019/222424, WO2019/226925, WO2019/232095, WO2019/232097, or WO2019/232208, the disclosure of WO2019/222424, WO2019/226925, WO2019/232095, WO2019/232097, or WO2019/232208 relating to liposomes or lipid-based carrier molecules herewith incorporated by reference.

In various embodiments, LNPs that suitably encapsulates the at least one nucleic acid of the invention have a mean diameter of from about 50 nm to about 200 nm, from about 60 nm to about 200 nm, from about 70 nm to about 200 nm, from about 80 nm to about 200 nm, from about 90 nm to about 200 nm, from about 90 nm to about 190 nm, from about 90 nm to about 180 nm, from about 90 nm to about 170 nm, from about 90 nm to about 160 nm, from about 90 nm to about 150 nm, from about 90 nm to about 140 nm, from about 90 nm to about 130 nm, from about 90 nm to about 120 nm, from about 90 nm to about 100 nm, from about 70 nm to about 90 nm, from about 80 nm to about 90 nm, from about 70 nm to about 80 nm, or about 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm, 85 nm, 90 nm, 95 nm, 100 nm, 105 nm, 110 nm, 115 nm, 120 nm, 125 nm, 130 nm, 135 nm, 140 nm, 145 nm, 150 nm, 160 nm, 170 nm, 180 nm, 190 nm, or 200 nm and are substantially non-toxic. As used herein, the mean diameter may be represented by the z-average as determined by dynamic light scattering as commonly known in the art.

The polydispersity index (PDI) of the nanoparticles is typically in the range of 0.1 to 0.5. In a particular embodiment, a PDI is below 0.2. Typically, the PDI is determined by dynamic light scattering.

In another preferred embodiment of the invention the lipid nanoparticles have a hydrodynamic diameter in the range from about 50 nm to about 300 nm, or from about 60 nm to about 250 nm, from about 60 nm to about 150 nm, or from about 60 nm to about 120 nm, respectively.

In another preferred embodiment of the invention the lipid nanoparticles have a hydrodynamic diameter in the range from about 50 nm to about 300 nm, or from about 60 nm to about 250 nm, from about 60 nm to about 150 nm, or from about 60 nm to about 120 nm, respectively.

In embodiments where more than one or a plurality, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 of nucleic acid species of the invention are comprised in the composition, said more than one or said plurality e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 of nucleic acid species of the invention may be complexed within one or more lipids thereby forming LNPs comprising more than one or a plurality, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 of different nucleic acid species.

According to a preferred embodiment the lipid-based carriers preferably encapsulating or comprising RNA are purified by by at least one purification step, preferably by at least one step of TFF and/or at least one step of clarification and/or at least one step of filtration. This purification particularly leads to reducing the amount of ethanol in the composition, which has been used for the lipid formulation.

In this context it is particularly preferred that the composition comprises after purification less than about 500ppM ethanol, preferably less than about 50ppM ethanol, more preferably less than about 5ppM ethanol.

In embodiments, the LNPs described herein may be lyophilized in order to improve storage stability of the formulation and/or the nucleic acid, preferably the RNA. In embodiments, the LNPs described herein may be spray dried in order to improve storage stability of the formulation and/or the nucleic acid. Lyoprotectants for lyophilization and or spray drying may be selected from trehalose, sucrose, mannose, dextran and inulin. A preferred lyoprotectant is sucrose, optionally comprising a further lyoprotectant. A further preferred lyoprotectant is trehalose, optionally comprising a further lyoprotectant.

Accordingly, the composition, e.g. the composition comprising LNPs is lyophilized (e.g. according to WO2016/165831 or WO2011/069586) to yield a temperature stable dried nucleic acid (powder) composition as defined herein (e.g. RNA or DNA). The composition, e.g. the composition comprising LNPs may also be dried using spray-drying or spray-freeze drying (e.g. according to WO2016/184575 or WO2016/184576) to yield a temperature stable composition (powder) as defined herein.

Accordingly, in preferred embodiments, the composition is a dried composition.

The term “dried composition” as used herein has to be understood as composition that has been lyophilized, or spray-dried, or spray-freeze dried as defined above to obtain a temperature stable dried composition (powder) e.g. comprising LNP complexed RNA (as defined above).

According to further embodiments, the composition of the second aspect may comprise at least one adjuvant.

Suitably, the adjuvant is preferably added to enhance the immunostimulatory properties of the composition.

The term “adjuvant” as used herein will be recognized and understood by the person of ordinary skill in the art, and is for example intended to refer to a pharmacological and/or immunological agent that may modify, e.g. enhance, the effect of other agents or that may be suitable to support administration and delivery of the composition. The term “adjuvant” refers to a broad spectrum of substances. Typically, these substances are able to increase the immunogenicity of antigens. For example, adjuvants may be recognized by the innate immune systems and, e.g., may elicit an innate immune response (that is, a non-specific immune response). “Adjuvants” typically do not elicit an adaptive immune response. In the context of the invention, adjuvants may enhance the effect of the antigenic peptide or protein provided by the nucleic acid. In that context, the at least one adjuvant may be selected from any adjuvant known to a skilled person and suitable for the present case, i.e. supporting the induction of an immune response in a subject, e.g. in a human subject.

Accordingly, the composition of the second aspect may comprise at least one adjuvant, wherein the at least one adjuvant may be suitably selected from any adjuvant provided in WO2016/203025. Adjuvants disclosed in any of the claims 2 to 17 of WO2016/203025, preferably adjuvants disclosed in claim 17 of WO2016/203025 are particularly suitable, the specific content relating thereto herewith incorporated by reference. Adjuvants may suitably used and comprised in the composition of the second aspect, or the vaccine of the forth aspect, to e.g. reduce the amount of nucleic acid required for a sufficient immune response against the encoded protein and/or to improve the efficacy of the composition/the vaccine for treatment/vaccination of the elderly. A suitable adjuvant in the context of a coronavirus composition or vaccine (in particular for compositions comprising a polypeptide of the third aspect) may be a Toll-like receptor 9 (TLR9) agonist adjuvant, CpG 1018TM.

The composition of the second aspect may comprise, besides the components specified herein, at least one further component which may be selected from the group consisting of further antigens (e.g. in the form of a peptide or protein, preferably derived from a coronavirus) or further antigen-encoding nucleic acids (preferably encoding peptide or protein, preferably derived from a coronavirus); a further immunotherapeutic agent; one or more auxiliary substances (cytokines, such as monokines, lymphokines, interleukins or chemokines); or any further compound, which is known to be immune stimulating due to its binding affinity (as ligands) to human Toll-like receptors; and/or an adjuvant nucleic acid, preferably an immunostimulatory RNA (isRNA), e.g. CpG-RNA etc.

In embodiments, a composition comprising lipid-based carriers encapsulating an RNA is stable after storage as a liquid, for example stable for at least 2 weeks after storage as a liquid at temperatures of about 5° C.

In some aspects, as used herein, “stable” refers to a liquid composition comprising lipid-based carriers encapsulating an RNA where the measured values for various physiochemical parameters are within a defined range after storage. In one embodiment, the liquid composition comprising lipid-based carriers encapsulating an RNA is analyzed to assess stability according to various parameters. Suitable stability parameters include, without limitation, RNA integrity, Z-average particle size, polydispersity index (PDI), the amount of free RNA in the liquid composition, encapsulation efficiency of the RNA (proportion of the RNA in percent incorporated with lipid-based carriers), shape and morphology of the lipid-based carriers encapsulating an RNA, pH, osmolality, or turbidity. Further, “stable” refers to a liquid composition comprising lipid-based carriers encapsulating an RNA where the measured values for various functional parameters are within a defined range after storage. In one embodiment, the liquid composition comprising lipid-based carriers encapsulating an RNA is analyzed to assess the potency of the liquid composition including for example the expression of the encoded peptide or protein, the induction of specific antibody titers, the induction of neutralizing antibody titers, the induction of T-cell, the reactogenicity of the liquid composition including for example the induction of innate immune responses etc.

In preferred embodiments, the term “stable” refers to RNA integrity.

In various embodiments, a composition of the embodiments is defined as a temperature stable liquid pharmaceutical composition and comprises a certain concentration of lipid-based carriers encapsulating an RNA which may be a suitable feature for achieving a temperature stability of the liquid composition. Without whishing to be bound to theory, a certain concentration of the RNA may have advantageous effects on temperature stability of the composition when stored as a liquid.

In embodiments, the concentration of the RNA in a composition is in a range of about 10 μg/ml to about 10 mg/ml. In embodiments, the concentration of the RNA in a liquid composition is in a range of about 100 μg/ml to about 5 mg/ml. In embodiments, the concentration of the RNA in the liquid composition is in a range of about 100 μg/ml to about 2 mg/ml. In embodiments, the concentration of the RNA in a liquid composition is in a range of about 100 μg/ml to about 1 mg/ml. In embodiments, the concentration of the RNA in a liquid composition is in a range of about 200 μg/ml to about 1 mg/ml. In embodiments, the concentration of RNA in a liquid composition is in a range of about 100 μg/ml to about 500 μg/ml. In preferred embodiments, the concentration of RNA in a liquid composition is in a range of about 200 μg/ml to about 500 μg/ml. In preferred embodiments, the concentration of RNA in the liquid composition is in a range of about 200 μg/ml to about 600 μg/ml. In preferred embodiments, the concentration of RNA in the liquid composition is in a range of about 200 μg/ml to about 700 μg/ml. In preferred embodiments, the concentration of RNA in the liquid composition is in a range of about 200 μg/ml to about 800 μg/ml. In preferred embodiments, the concentration of RNA in the liquid composition is in a range of about 200 μg/ml to about 900 μg/ml.

In embodiments, the concentration of RNA in a composition is for example about 100 μg/ml, about 200 μg/ml, about 300 μg/ml, about 400 μg/ml, about 500 μg/ml, about 600 μg/ml, about 700 μg/ml, about 800 μg/ml, about 900 μg/ml, about 1 mg/ml. In preferred embodiments, the concentration of the RNA in the liquid composition is at least 100 μg/ml, preferably at least 200 μg/ml, more preferably at least 500 μg/ml.

In various embodiments, RNA of a pharmaceutical composition has a certain RNA integrity which may be a suitable feature for achieving a temperature stability of the liquid composition.

The term “RNA integrity” generally describes whether the complete RNA sequence is present in the liquid composition. Low RNA integrity could be due to, amongst others, RNA degradation, RNA cleavage, incorrect or incomplete chemical synthesis of the RNA, incorrect base pairing, integration of modified nucleotides or the modification of already integrated nucleotides, lack of capping or incomplete capping, lack of polyadenylation or incomplete polyadenylation, or incomplete RNA in vitro transcription. RNA is a fragile molecule that can easily degrade, which may be caused e.g. by temperature, ribonucleases, pH or other factors (e.g. nucleophilic attacks, hydrolysis etc.), which may reduce the RNA integrity and, consequently, the functionality of the RNA.

The skilled person can choose from a variety of different chromatographic or electrophoretic methods for determining an RNA integrity. Chromatographic and electrophoretic methods are well-known in the art. In case chromatography is used (e.g. RP-HPLC), the analysis of the integrity of the RNA may be based on determining the peak area (or “area under the peak”) of the full length RNA in a corresponding chromatogram. The peak area may be determined by any suitable software which evaluates the signals of the detector system. The process of determining the peak area is also referred to as integration. The peak area representing the full length RNA is typically set in relation to the peak area of the total RNA in a respective sample. The RNA integrity may be expressed in % RNA integrity.

In the context of aspects of the invention, RNA integrity may be determined using analytical (RP)HPLC. Typically, a test sample of the liquid composition comprising lipid based carrier encapsulating RNA may be treated with a detergent (e.g. about 2% Triton X100) to dissociate the lipid based carrier and to release the encapsulated RNA. The released RNA may be captured using suitable binding compounds, e.g. Agencourt AMPure XP beads (Beckman Coulter, Brea, Calif., USA) essentially according to the manufacturer's instructions. Following preparation of the RNA sample, analytical (RP)HPLC may be performed to determine the integrity of RNA. Typically, for determining RNA integrity, the RNA samples may be diluted to a concentration of 0.1 g/l using e.g. water for injection (WFI). About 10 μl of the diluted RNA sample may be injected into an HPLC column (e.g. a monolithic poly(styrene-divinylbenzene) matrix). Analytical (RP)HPLC may be performed using standard conditions, for example: Gradient 1: Buffer A (0.1M TEAA (pH 7.0)); Buffer B (0.1M TEAA (pH 7.0) containing 25% acetonitrile). Starting at 30% buffer B the gradient extended to 32% buffer B in 2 min, followed by an extension to 55% buffer B over 15 minutes at a flow rate of 1 ml/min. HPLC chromatograms are typically recorded at a wavelength of 260 nm. The obtained chromatograms may be evaluated using a software and the relative peak area may be determined in percent (%) as commonly known in the art. The relative peak area indicates the amount of RNA that has 100% RNA integrity. Since the amount of the RNA injected into the HPLC is typically known, the analysis of the relative peak area provides information on the integrity of the RNA. Thus, if e.g. 100 ng RNA have been injected in total, and 100 ng are determined as the relative peak area, the RNA integrity would be 100%. If, for example, the relative peak area would correspond to 80 ng, the RNA integrity would be 80%. Accordingly, RNA integrity in the context of the invention is determined using analytical HPLC, preferably analytical RP-HPLC.

In certain embodiments, a pharmaceutical of the embodiments is stable for about 2 weeks to about 1 month, 2 months, 3 months, 4 months, 5 months, 6 months or 1 year after storage as a liquid at temperatures of about 5° C. For example, at least about 50%, 60%, 70%, 75%, 80%, 85%, 90% or 95% of the RNA remains intact after storage as a liquid for at least about 5° C. for about two weeks, three weeks, one month, 6 weeks, 2 months, 3 months, 4 months, 5 months, 6 months or 1 year. In some aspects, a temperature stable liquid pharmaceutical of the embodiments comprises at least about 70%, 75%, 80%, 85%, 90% or 95% of intact RNA at least about two weeks after storage as a liquid at temperatures of about 5° C. In further aspects, a temperature stable liquid pharmaceutical of the embodiments comprises at least about 70%, 75%, 80%, 85%, 90% or 95% of intact RNA at least 1 month after storage as a liquid at temperatures of about 5° C. In certain aspects, a temperature stable liquid pharmaceutical of the embodiments comprises at least about 70%, 75%, 80%, 85%, 90% or 95% of intact RNA at least about 2 weeks to about 1 month, 2 months, 3 months, 4 months, 5 months, 6 months or 1 year after storage as a liquid at temperatures of about 5° C. I some specific aspects, a temperature stable liquid pharmaceutical of the embodiments comprises at least about 80% of intact RNA after about two weeks of storage as a liquid at temperatures of about 5° C.

In certain embodiments, RNA of a composition has an RNA integrity ranging from about 40% to about 100%. In embodiments, the RNA has an RNA integrity ranging from about 50% to about 100%. In embodiments, the RNA has an RNA integrity ranging from about 60% to about 100%. In embodiments, the RNA has an RNA integrity ranging from about 70% to about 100%. In embodiments, the RNA integrity is for example about 50%, about 60%, about 70%, about 80%, or about 90%. RNA is suitably determined using analytical HPLC, preferably analytical RP-HPLC.

In preferred embodiments, the RNA of a composition has an RNA integrity of at least about 50%, preferably of at least about 60%, more preferably of at least about 70%, most preferably of at least about 80% or ABOUT 90%. RNA is suitably determined using analytical HPLC, preferably analytical RP-HPLC.

In various embodiments, nucleic acid, e.g., RNA of a pharmaceutical composition does not exceed a certain proportion of free RNA, which may be a suitable feature for achieving a temperature stability of the liquid composition. Without wishing to be bound to theory, free RNA in the liquid composition may be more vulnerable to degradation as the RNA that is encapsulated in the lipid based carrier.

In certain aspects, compositions of the embodiments comprise RNA. In this context, the term “free RNA” or “non-complexed RNA” or “non-encapsulated RNA” comprise the RNA molecules that are not encapsulated in the lipid-based carriers as defined herein. During formulation of the liquid composition (e.g. during encapsulation of the RNA into the lipid-based carriers), free RNA may represent a contamination or an impurity. A large proportion of non-encapsulated or free RNA may also be an indicator for destabilization of a lipid-based carriers of the composition (e.g. upon storage of the composition). For example, free RNA detectable in the liquid composition may increase during storage, which may be used as a feature to determine the temperature stability of the composition.

The skilled person can choose from a variety of different methods for determining the amount and/or the proportion of free nucleic acid of free RNA in the liquid composition. Free RNA in the liquid composition may be determined by chromatographic methods (e.g. AEX, SEC) or by using probes (e.g. dyes) that bind to free RNA in the composition. In the context of the invention, the amount of free RNA or non-encapsulated RNA may be determined using a dye based assay. Suitable dyes that may be used to determine the amount and/or the proportion of free RNA comprise RiboGreen®, PicoGreen® dye, OliGreen® dye, QuantiFluor® RNA dye, Qubit® RNA dye, Quant-iT™ RNA dye, TOTO®-1 dye, YOYO®-1 dye. Such dyes are suitable to discriminate between free RNA and encapsulated RNA. Reference standards consisting of defined amounts of free RNA or encapsulated RNA may be used and mixed with the respective reagent (e.g. RiboGreen® reagent (Excitation 500 nm/Emission 525 nm)) as recommended by the supplier's instructions. Typically, the free RNA of the liquid composition is quantitated using the Quant-iT RiboGreen RNA Reagent according to the manufacturer's instructions. The proportion of free RNA in the context of the invention is typically determined using a RiboGreen assay.

In embodiments, a composition comprises free nucleic acid, such as free RNA ranging from about 30% to about 0%. In embodiments, the liquid composition comprises about 20% free RNA (and about 80% encapsulated RNA), about 15% free RNA (and about 85% encapsulated RNA), about 10% free RNA (and about 90% encapsulated RNA), or about 5% free RNA (and about 95% encapsulated RNA). In preferred embodiments, the liquid composition comprises less than about 20% free RNA, preferably less than about 15% free RNA, more preferably less than about 10% free RNA, most preferably less than about 5% free RNA.

In aspects comprising RNA nucleic acids, the term “encapsulated RNA” comprise the RNA molecules that are encapsulated in the lipid-based carriers as defined herein. The proportion of encapsulated RNA in the context of the invention is typically determined using a RiboGreen assay.

Accordingly, in embodiments, about 70% to about 100% of the RNA in the liquid composition is encapsulated in the lipid-based carriers. In embodiments, the liquid composition comprises about 80% encapsulated RNA (and about 20% free RNA), about 85% encapsulated RNA (and about 15% free RNA), about 90% encapsulated RNA (and about 10% free RNA), or about 95% encapsulated RNA (and 5% about free RNA).

In preferred embodiments, 80% of the nucleic acid (e.g., RNA) comprised in the liquid composition is encapsulated, preferably 85% of the RNA comprised in the composition is encapsulated, more preferably 90% of the RNA comprised in the composition is encapsulated, most preferably 95% of the RNA comprised in the composition is encapsulated.

In various embodiments, a pharmaceutical composition (in particular the RNA of the composition) does not exceed a certain amount of divalent cations, which may be a suitable feature for achieving temperature stability of the liquid composition. Divalent cations, e.g. divalent metal ions (e.g. Mg2+, Ca2+, Mn2+, Zn2+, Ni2+, Fe2+, Co2+, Pb2+) may cause hydrolysis of the RNA encapsulated in the lipid-based carriers during storage as a liquid.

In some aspects, RNA of a composition may typically be produced by RNA in vitro transcription (IVT) of a (linear) DNA template. Common RNA in vitro transcription buffers comprise large amounts of MgCl2 (e.g. 5 mM, 15 mM or more) which is a co-factor of the RNA polymerase. Accordingly, the obtained in vitro transcribed RNA may comprise Mg2+ ions as a contamination. After RNA in vitro transcription, the DNA template is typically removed by means of DNAses. Common buffers for DNAse digest comprise large amounts of CaCl2) (e.g. 1 mM, 5 mM or more) which is a co-factor of the DNAse. Accordingly, the obtained in vitro transcribed RNA may comprise Ca2+ as a contamination.

Typically, various RNA purification steps (e.g. RP-HPLC, tangential flow filtration) may be employed to remove various contaminations including divalent metal ions. Suitably, the RNA used for encapsulation in the lipid-based carriers of the invention has been purified to remove divalent metal ions.

In embodiments, a composition of the embodiments comprises less than about 100 nM divalent cations per g RNA, preferably less than about 50 nM divalent cations per g RNA, more preferably less than about 10 nM divalent cations per g RNA. In embodiments, the divalent cations are selected from Mg2+ and/or Ca2+. In embodiments, the liquid composition comprises less than about 100 nM Mg2+ per g RNA. In embodiments, the liquid composition comprises less than about 100 nM Ca2 per g RNA. Typically, Ion Chromatography (IC) coupled with Inductively Coupled Plasma Mass Spectrometry (IC-ICP-MS) may be used for determination of divalent cations.

In embodiments, the lipid-based carrier encapsulating the RNA of a composition comprises less than about 100 nM divalent cations per g RNA, preferably less than about 50 nM divalent cations per g RNA, more preferably less than about 10 nM divalent cations per g RNA. In embodiments, the divalent cations are selected from Mg2+ and/or Ca2+. In embodiments, the lipid-based carriers encapsulating the RNA comprise less than about 100 nM Mg2+ per g RNA. In embodiments, the lipid-based carriers encapsulating the RNA comprises less than about 100 nM Ca2 per g RNA. Typically, Ion Chromatography (IC) coupled with Inductively Coupled Plasma Mass Spectrometry (IC-ICP-MS) may be used for determination of Mg2+ and/or Ca2+.

In embodiments, the RNA of a composition comprises Na+ as a counter ion. In embodiments, the RNA comprises Na+ in an amount ranging from about 10 μg Na+ per g RNA to about 1 mg Na+ per g RNA. In embodiments, the RNA comprises Na+ as a counter ion in an amount of at least about 100 μg Na+ per g RNA, preferably at least about 200 μg Na+ per g RNA. Typically, Ion Chromatography (IC) coupled with Inductively Coupled Plasma Mass Spectrometry (IC-ICP-MS) may be used for determination of Na+.

In embodiments, the composition comprises at least one antagonist of at least one RNA sensing pattern recognition receptor. Such an antagonist may preferably be co-formulated in lipid-based carriers as defined herein.

Suitable antagonist of at least one RNA sensing pattern recognition receptor are disclosed in PCT patent application PCT/EP2020/072516, the full disclosure herewith incorporated by reference. In particular, the disclosure relating to suitable antagonist of at least one RNA sensing pattern recognition receptors as defined in any one of the claims 1 to 94 of PCT/EP2020/072516 are incorporated.

In preferred embodiments, the composition comprises at least one antagonist of at least one RNA sensing pattern recognition receptor selected from a Toll-like receptor, preferably TLR7 and/or TLR8.

In embodiments, the at least one antagonist of at least one RNA sensing pattern recognition receptor is selected from a nucleotide, a nucleotide analog, a nucleic acid, a peptide, a protein, a small molecule, a lipid, or a fragment, variant or derivative of any of these.

In preferred embodiments, the at least one antagonist of at least one RNA sensing pattern recognition receptor is a single stranded oligonucleotide, preferably a single stranded RNA Oligonucleotide.

In embodiments, the antagonist of at least one RNA sensing pattern recognition receptor is a single stranded oligonucleotide that comprises or consists of a nucleic acid sequence identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 85-212 of PCT/EP2020/072516, or fragments of any of these sequences.

In preferred embodiments, the antagonist of at least one RNA sensing pattern recognition receptor is a single stranded oligonucleotide that comprises or consists of a nucleic acid sequence identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 85-87, 149-212 of PCT/EP2020/072516, or fragments of any of these sequences.

A particularly preferred antagonist of at least one RNA sensing pattern recognition receptor in the context of the invention is 5′-GAG CGmG CCA-3′ (SEQ ID NO: 85 of PCT/EP2020/072516), or a fragment thereof.

In embodiments, the molar ratio of the at least one antagonist of at least one RNA sensing pattern recognition receptor as defined herein to the at least one nucleic acid, preferably RNA encoding a SRAS-CoV-2 antigenic peptide or protein as defined herein suitably ranges from about 1:1, to about 100:1, or ranges from about 20:1, to about 80:1.

In embodiments, the wherein the weight to weight ratio of the at least one antagonist of at least one RNA sensing pattern recognition receptor as defined herein to the at least one nucleic acid, preferably RNA encoding a SRAS-CoV-2 antigenic peptide or protein as defined herein suitably ranges from about 1:1, to about 1:30, or ranges from about 1:2, to about 1:10.

Polypeptide for a Coronavirus Vaccine

In a third aspect, the present invention provides an antigenic polypeptide suitable for a coronavirus vaccine, in particular for a SARS-CoV-2 (formerly nCoV-2019) coronavirus vaccine. In preferred embodiments, the polypeptide is derived from any protein or fragment thereof that a nucleic acid of the first aspect is encoding. Preferred polypeptide designs are disclosed in List 1.

In preferred embodiments, the amino acid sequences of the antigenic polypeptide of the third aspect is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of amino acid sequences SEQ ID NOs: 1-111, 274-11663, 13176-13510, 13521-14123, 22732-22758, 22917, 22923, 22929-22964, 26938, 26939 or fragment or variant of any of these.

The polypeptide of the third aspect may also be comprised in a (pharmaceutical) composition, including pharmaceutically acceptable carriers, or adjuvants as defined herein, in particular as defined in the context of the second aspect. Accordingly, the invention also relates to a (pharmaceutical) composition comprising said antigenic polypeptide.

The polypeptide of the third aspect may also be comprised in vaccine, including pharmaceutically acceptable carriers, or adjuvants as defined herein, in particular as defined in the context of the fourth aspect. Accordingly, the invention also relates to a vaccine comprising said antigenic polypeptide (see fourth aspect). Suitable adjuvants that may be used in combination with a polypeptide as defined herein are saponin-based adjuvants (steroid or triterpenoid glycosides), e.g. Matrix-M adjuvant.

Vaccine:

In a fourth aspect, the present invention provides a vaccine against a coronavirus, preferably against a SARS-CoV-2 (formerly nCoV-2019) coronavirus causing COVID-19 disease.

In preferred embodiments of the fourth aspect, the vaccine comprises at least one nucleic acid (e.g. DNA or RNA), preferably at least one RNA of the first aspect, or the composition of the second aspect.

In other embodiments, the vaccine comprises at least one polypeptide as defined in the third aspect.

In other embodiments, the vaccine comprises at least one plasmid DNA or adenovirus DNA as defined in the first aspect.

Notably, embodiments relating to the composition of the second aspect may likewise be read on and be understood as suitable embodiments of the vaccine of the fourth aspect. Also, embodiments relating to the vaccine of the fourth aspect may likewise be read on and be understood as suitable embodiments of the composition of the second aspect. Furthermore, features and embodiments described in the context of the first aspect (the nucleic acid of the invention) have to be read on and have to be understood as suitable embodiments of the composition of the fourth aspect.

The term “vaccine” will be recognized and understood by the person of ordinary skill in the art, and is for example intended to be a prophylactic or therapeutic material providing at least one epitope or antigen, preferably an immunogen. In the context of the invention the antigen or antigenic function is suitably provided by the inventive nucleic acid of the first aspect (said nucleic acid comprising a coding sequence encoding a antigenic peptide or protein derived from a SARS-CoV-2 coronavirus) or the composition of the second aspect (comprising at least one nucleic acid of the first aspect). In other embodiments, the antigen or antigenic function is provided by the inventive polypeptide of the third aspect.

In preferred embodiments, the vaccine, or the composition of the second aspect, elicits an adaptive immune response, preferably an adaptive immune response against a coronavirus, preferably against SARS-CoV-2 coronavirus.

In particularly preferred embodiments, the vaccine, or the composition of the second aspect, elicits functional antibodies that can effectively neutralize the virus, preferably SARS-CoV-2 coronavirus.

In further preferred embodiments, the vaccine, or the composition of the second aspect, elicits mucosal IgA immunity by inducing of mucosal IgA antibodies.

In particularly preferred embodiments, the vaccine, or the composition of the second aspect, elicits functional antibodies that can effectively neutralize the virus, preferably SARS-CoV-2 coronavirus.

In further particularly preferred embodiments, the vaccine, or the composition of the second aspect, induces broad, functional cellular T-cell responses against coronavirus, preferably against SARS-CoV-2 coronavirus.

In further particularly preferred embodiments, the vaccine, or the composition of the second aspect, induces a well-balanced B cell and T cell response against coronavirus, preferably against SARS-CoV-2 coronavirus.

According to a preferred embodiment, the vaccine as defined herein may further comprise a pharmaceutically acceptable carrier and optionally at least one adjuvant as specified in the context of the second aspect.

Suitable adjuvants in that context may be selected from adjuvants disclosed in claim 17 of WO2016/203025.

In a preferred embodiment, the vaccine is a monovalent vaccine.

The terms “monovalent vaccine”, “monovalent composition” “univalent vaccine” or “univalent composition” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a composition or a vaccine comprising only one antigen or antigen construct from a pathogen. Accordingly, said vaccine or composition comprises only one nucleic acid species encoding a single antigen or antigen construct of a single organism. The term “monovalent vaccine” includes the immunization against a single valence. In the context of the invention, a monovalent SARS-CoV-2 coronavirus vaccine or composition would comprise at least one nucleic acid encoding one single antigenic peptide or protein derived from one specific SARS-CoV-2 coronavirus.

In embodiments, the vaccine is a polyvalent vaccine comprising a plurality or at least more than one of the nucleic acid species defined in the context of the first aspect. Embodiments relating to a polyvalent composition as disclosed in the context of the second aspect may likewise be read on and be understood as suitable embodiments of the polyvalent vaccine.

The terms “polyvalent vaccine”, “polyvalent composition” “multivalent vaccine” or “multivalent composition” will be recognized and understood by the person of ordinary skill in the art, and are e.g. intended to refer to a composition or a vaccine comprising antigens from more than one virus (e.g. different SARS-CoV-2 coronavirus isolates), or comprising different antigens or antigen constructs of the same SARS-CoV-2 coronavirus, or any combination thereof. The terms describe that said vaccine or composition has more than one valence. In the context of the invention, a polyvalent SARS-CoV-2 coronavirus vaccine would comprise nucleic acid sequences encoding antigenic peptides or proteins derived from several different SARS-CoV-2 coronavirus (e.g. different SARS-CoV-2 coronavirus isolates) or comprising nucleic acid sequences encoding different antigens or antigen constructs from the same SARS-CoV-2 coronavirus, or a combination thereof.

In preferred embodiments, the polyvalent or multivalent vaccine comprises at least one polyvalent composition as defined in the second aspect. Particularly preferred are polyvalent compositions as defined in section “Multivalent compositions of the invention”.

In embodiments, the vaccine comprises at least one antagonist of at least one RNA sensing pattern recognition receptor as defined in the second aspect.

The coronavirus vaccine typically comprises a safe and effective amount of nucleic acid (e.g. DNA or RNA), preferably RNA of the first aspect or composition of the second aspect (or the polypeptide of the third aspect). As used herein, “safe and effective amount” means an amount of nucleic acid or composition sufficient to significantly induce a positive modification of a disease or disorder related to an infection with coronavirus, preferably SARS-CoV-2 coronavirus. At the same time, a “safe and effective amount” is small enough to avoid serious side-effects. In relation to the nucleic acid, composition, or vaccine of the present invention, the expression “safe and effective amount” preferably means an amount of nucleic acid, composition, or vaccine that is suitable for stimulating the adaptive immune system against coronavirus in such a manner that no excessive or damaging immune reactions (e.g. innate immune responses) are achieved.

A “safe and effective amount” of the nucleic acid, composition, or vaccine as defined above will vary in connection with the particular condition to be treated and also with the age and physical condition of the patient to be treated, the severity of the condition, the duration of the treatment, the nature of the accompanying therapy, of the particular pharmaceutically acceptable carrier used, and similar factors, within the knowledge and experience of the skilled person. Moreover, the “safe and effective amount” of the nucleic acid, the composition, or vaccine may depend from application/delivery route (intradermal, intramuscular, intranasal), application device (jet injection, needle injection, microneedle patch, electroporation device) and/or complexation/formulation (protamine complexation or LNP encapsulation, DNA or RNA). Moreover, the “safe and effective amount” of the nucleic acid, the composition, or the vaccine may depend from the physical condition of the treated subject (infant, pregnant women, immunocompromised human subject etc.).

The coronavirus vaccine can be used according to the invention for human medical purposes and also for veterinary medical purposes (mammals, vertebrates, or avian species).

The pharmaceutically acceptable carrier as used herein preferably includes the liquid or non-liquid basis of the inventive coronavirus vaccine. If the inventive vaccine is provided in liquid form, the carrier will be water, typically pyrogen-free water; isotonic saline or buffered (aqueous) solutions, e.g. phosphate, citrate etc. buffered solutions. Preferably, Ringer-Lactate solution is used as a liquid basis for the vaccine or the composition according to the invention as described in WO2006/122828, the disclosure relating to suitable buffered solutions incorporated herewith by reference. Other preferred solutions used as a liquid basis for the vaccine or the composition, in particular for compositions/vaccines comprising LNPs, comprise sucrose and/or trehalose.

The choice of a pharmaceutically acceptable carrier as defined herein is determined, in principle, by the manner, in which the pharmaceutical composition(s) or vaccine according to the invention is administered. The coronavirus vaccine is preferably administered locally. Routes for local administration in general include, for example, topical administration routes but also intradermal, transdermal, subcutaneous, or intramuscular injections or intralesional, intracranial, intrapulmonal, intracardial, intraarticular and sublingual injections. More preferably, composition or vaccines according to the present invention may be administered by an intradermal, subcutaneous, or intramuscular route, preferably by injection, which may be needle-free and/or needle injection. Preferred in the context of the invention is intramuscular injection. Compositions/vaccines are therefore preferably formulated in liquid or solid form. The suitable amount of the vaccine or composition according to the invention to be administered can be determined by routine experiments, e.g. by using animal models. Such models include, without implying any limitation, rabbit, sheep, mouse, rat, dog and non-human primate models. Preferred unit dose forms for injection include sterile solutions of water, physiological saline or mixtures thereof. The pH of such solutions should be adjusted to about 7.4.

The inventive coronavirus vaccine or composition as defined herein may comprise one or more auxiliary substances or adjuvants as defined above in order to further increase the immunogenicity. A synergistic action of the nucleic acid contained in the inventive composition/vaccine and of an auxiliary substance, which may be optionally be co-formulated (or separately formulated) with the inventive vaccine or composition as described above, is preferably achieved thereby. Such immunogenicity increasing agents or compounds may be provided separately (not co-formulated with the inventive vaccine or composition) and administered individually.

The coronavirus vaccine is preferably provided in lyophilized or spray-dried form (as described in the context of the second aspect). Such a lyophilized or spray-dried vaccine is typically comprises trehalose and/or sucrose and is re-constituted in a suitable liquid buffer before administration to a subject. In some aspects, a lyophilized vaccine of the embodiments comprises mRNA of the embodiments complexed with LNPs. In some aspects, a lyophilized composition has a water content of less than about 10%. For example, a lyophilized composition can have a water content of about 0.1% to 10%, 0.1% to 7.5%, or 0.5% to 7.5%, preferably the lyophilized composition has a water content of about 0.5% to about 5.0%.

In preferred embodiments administration of a therapeutically effective amount of the nucleic acid, the composition, the polypeptide, the vaccine to a subject induces a neutralizing antibody titer against SARS-CoV-2 coronavirus in the subject.

In some embodiments, the neutralizing antibody titer is at least 100 neutralizing units per milliliter (NU/mL), at least 500 NU/mL, or at least 1000 NU/mL.

In some embodiments, detectable levels of the coronavirus antigen are produced in the subject at about 1 to about 72 hours post administration of the nucleic acid, the composition, the polypeptide, or the vaccine.

In some embodiments, a neutralizing antibody titer (against coronavirus) of at least 100 NU/ml, at least 500 NU/ml, or at least 1000 NU/ml is produced in the serum of the subject at about 1 day to about 72 days post administration of the nucleic acid, the composition, the polypeptide, or the vaccine.

In some embodiments, the neutralizing antibody titer is sufficient to reduce coronavirus infection by at least 50% relative to a neutralizing antibody titer of an unvaccinated control subject or relative to a neutralizing antibody titer of a subject vaccinated with a live attenuated viral vaccine, an inactivated viral vaccine, or a protein sub unit viral vaccine.

In some embodiments, the neutralizing antibody titer and/or a T cell immune response is sufficient to reduce the rate of asymptomatic viral infection relative to the neutralizing antibody titer of unvaccinated control subjects.

In some embodiments, the neutralizing antibody titer and/or a T cell immune response is sufficient to prevent viral latency in the subject.

In some embodiments, the neutralizing antibody titer is sufficient to block fusion of virus with epithelial cells of the subject.

In some embodiments, the neutralizing antibody titer is induced within 20 days following a single 1 ug-100 ug dose of the nucleic acid, the composition, the polypeptide, or the vaccine, or within 40 days following a second 1 ug-100 μg dose of the nucleic acid, the composition, the polypeptide, or the vaccine.

In preferred embodiments, administration of a therapeutically effective amount of the nucleic acid, the composition, the polypeptide, or the vaccine to a subject induces a T cell immune response against coronavirus in the subject. In preferred embodiments, the T cell immune response comprises a CD4+ T cell immune response and/or a CD8+ T cell immune response.

Kit or Kit of Parts, Application, Medical Uses, Method of Treatment:

In a fifth aspect, the present invention provides a kit or kit of parts suitable for treating or preventing a coronavirus infection. Preferably, said kit or kit of parts is suitable for treating or preventing a coronavirus, preferably a SARS-CoV-2 (formerly nCoV-2019) coronavirus infection.

Notably, embodiments relating to the nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, and the vaccine of the fourth aspect may likewise be read on and be understood as suitable embodiments of the kit or kit of parts of the fifth aspect of the invention.

In preferred embodiments, the kit or kit of parts comprises at least one nucleic acid (e.g. RNA or DNA), preferably at least one RNA of the first aspect, at least one composition of the second aspect, and/or at least one polypeptide of the third aspect, and/or at least one vaccine of the forth aspect.

In embodiments, the kit or kit of parts comprises at least one DNA as defined in the first aspect, e.g. at least one plasmid DNA and/or at least one adenovirus DNA.

In embodiments, the kit or kit of parts comprises at least one polypeptide as defined in the third aspect.

In addition, the kit or kit of parts may comprise a liquid vehicle for solubilising, and/or technical instructions providing information on administration and dosage of the components.

The kit may further comprise additional components as described in the context of the composition of the second aspect, and/or the vaccine of the forth aspect.

The technical instructions of said kit may contain information about administration and dosage and patient groups. Such kits, preferably kits of parts, may be applied e.g. for any of the applications or uses mentioned herein, preferably for the use of the nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, or the vaccine of the forth aspect, for the treatment or prophylaxis of an infection or diseases caused by a coronavirus, preferably SARS-CoV-2 coronavirus, or disorders related thereto.

Preferably, the nucleic acid, the composition, the polypeptide, or the vaccine is provided in a separate part of the kit, wherein the nucleic acid, the composition, the polypeptide, or the vaccine is preferably lyophilised.

The kit may further contain as a part a vehicle (e.g. buffer solution) for solubilising the nucleic acid, the composition, the polypeptide, or the vaccine.

In preferred embodiments, the kit or kit of parts as defined herein comprises Ringer lactate solution.

In preferred embodiments, the kit or kit of parts as defined herein comprises a multidose container for administration of the composition/the vaccine.

Any of the above kits may be used in a treatment or prophylaxis as defined herein. More preferably, any of the above kits may be used as a vaccine, preferably a vaccine against infections caused by a coronavirus, preferably caused by SARS-CoV-2 coronavirus.

In preferred embodiments, the kit or kit of parts comprises the following components:

• a) at least one container or vial comprising a composition or SARS-CoV-2 vaccine as defined herein, wherein the composition or SARS-CoV-2 vaccine has a nucleic acid concentration, preferably an RNA concentration in a range of about 100 μg/ml to about 1 mg/ml, preferably in a range of about 100 μg/ml to about 500 μg/ml, e.g. about 270 μg/ml.


• b) at least one dilution container or vial comprising a sterile dilution buffer, suitably a buffer comprising NaCl, optionally comprising a preservative;


• c) at least one means for transferring the composition or vaccine from the storage container to the dilution container; and


• d) at least one syringe for administering the final diluted composition or vaccine to a subject, preferably configured for intramuscular administration to a human subject, wherein the final diluted composition or vaccine has a nucleic acid concentration, preferably an RNA concentration in a range of about 10 μg/ml to about 100 μg/ml, preferably in a range of about 10 μg/ml to about 50 μg/ml, e.g. about 24 μg/ml

In an embodiment, the kit or kit of parts comprises more than one mRNA-based SARS-CoV-2 composition/vaccine, preferably

• 
  
  
  
  • at least one vaccine as defined herein provided in a first vial or container, wherein the vaccine comprises at least one nucleic acid, preferably RNA, which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO. 163, 149 or 24837, preferably formulated in lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45 (ALC-0159)). Preferably, the nucleic acid, preferably mRNA is not chemically modified.
  
  
  • at least one further vaccine as defined herein provided in a first vial or container, wherein the composition/vaccine comprises at least one nucleic acid, preferably RNA, which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence of SEQ ID NO: 23311, 23531, 24851, 23310, 23530, 24850, 23313, 23533, 24853, 23314, 23534, or 24854, preferably formulated in lipid nanoparticles (LNPs), which have a molar ratio of approximately 50:10:38.5:1.5, preferably 47.5:10:40.8:1.7 or more preferably 47.4:10:40.9:1.7 proportion (mol %) of cationic lipid III-3 (ALC-0315), DSPC, cholesterol and PEG-lipid of formula (IVa) (with n=49 or with n=45 (ALC-0159)). Preferably, the nucleic acid, preferably mRNA is not chemically modified.
  
  
  
  

In an embodiment, the kit or kit of parts comprises two different SARS-CoV-2 vaccines for prime vaccination and boost vaccination:

• 
  
  
  
  • at least one prime vaccine as defined herein provided in a first vial or container, wherein the vaccine is an mRNA-based SARS-CoV-2 vaccine as defined herein; and
  
  
  • at least one boost vaccine as defined herein provided in a first vial or container, wherein the composition/vaccine is an adenovirus-based SARS-CoV-2 vaccine as defined herein.
  
  
  
  

In an embodiment, the kit or kit of parts comprises two different SARS-CoV-2 vaccines for prime vaccination and boost vaccination:

• 
  
  
  
  • at least one boost vaccine as defined herein provided in a first vial or container, wherein the vaccine is an mRNA-based SARS-CoV-2 vaccine as defined herein; and
  
  
  • at least one prime vaccine as defined herein provided in a first vial or container, wherein the composition/vaccine is an adenovirus-based SARS-CoV-2 vaccine as defined herein.
  
  
  
  

Combination:

A sixth aspect relates to a combination of at least two nucleic acid sequences as defined in the first aspect, at least two compositions as defined in the context of the second aspect, at least two polypeptides as defined in the third aspect, at least two vaccines as defined in the context of the fourth aspect, or at least two kits as defined in the fifth aspect.

In the context of the present invention, the term “combination” preferably means a combined occurrence of at least two components, preferably at least two nucleic acid sequences as defined in the first aspect, at least two compositions as defined in the context of the second aspect, at least two polypeptides as defined in the third aspect, at least two vaccines as defined in the context of the fourth aspect, or at least two kits as defined in the fifth aspect. The components of such a combination may occur as separate entities. Thus, the administration of the components of the combination may occur either simultaneously or timely staggered, either at the same site of administration or at different sites of administration.

Notably, embodiments relating to the nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, and the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect may likewise be read on and be understood as suitable embodiments of the components of the combination of the sixth aspect.

In embodiments, the combination may comprise a plurality or at least more than one of the nucleic acid species, e.g. RNA species as defined in the context of the first aspect of the invention, wherein the nucleic acid species are provided as separate components.

Preferably, the combination as defined herein may comprise 2, 3, 4, 5, 6, 7, 8, 9, or 10 different nucleic acids e.g. RNA species as defined in the context of the first aspect of the invention; 2, 3, 4, 5, 6, 7, 8, 9, or 10 different compositions as defined in the context of the second aspect of the invention; 2, 3, 4, 5, 6, 7, 8, 9, or 10 different polypeptides as defined in the context of the third aspect of the invention; 2, 3, 4, 5, 6, 7, 8, 9, or 10 different vaccines as defined in the context of the third aspect of the invention, wherein the nucleic acid species, compositions, polypeptides, vaccines are provided as separate components.

In embodiments, the combination comprises 2, 3, 4 or 5 nucleic acid species (e.g. DNA or RNA) comprised in separate components, preferably RNA species, wherein said nucleic acid species comprise or consist of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 116-132, 134-138, 140-143, 145-175, 11664-11813, 11815, 11817-12050, 12052, 12054-13147, 13514, 13515, 13519, 13520, 14124-14177, 22759, 22764-22786, 22791-22813, 22818-22839, 22969-23184, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 and, optionally, at least one pharmaceutically acceptable carrier or excipient, wherein each of the 2, 3, 4 or 5 nucleic acid species encode a different antigenic peptide or protein of a SARS-CoV-2 coronavirus.

Accordingly, in embodiments, the combination comprises two nucleic acid species (e.g. DNA or RNA)) comprised in separate components, preferably RNA species, wherein the nucleic acid species comprise or consist of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937148 and, optionally, at least one pharmaceutically acceptable carrier or excipient, wherein each of the two nucleic acid species encode a different antigenic peptide or protein of a SARS-CoV-2 coronavirus.

In embodiments, the combination comprises three nucleic acid species (e.g. DNA or RNA)) comprised in separate components, preferably RNA species, wherein the nucleic acid comprises or consists of a nucleic acid sequence which is identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence selected from the group consisting of SEQ ID NOs: 148-175, 12204-13147, 14142-14177, 22786-22839, 23189-23404, 23409-23624, 23629-23844, 23849-24064, 24069-24284, 24289-24504, 24509-24724, 24729-24944, 24949-25164, 25169-25384, 25389-25604, 25609-25824, 25829-26044, 26049-26264, 26269-26484, 26489-26704, 26709-26937 and, optionally, at least one pharmaceutically acceptable carrier or excipient, wherein each of the 2, 3, 4 or 5 nucleic acid species encode a different antigenic peptide or protein of a SARS-CoV-2 coronavirus.

In the following, particularly preferred embodiments of a combination are provided, wherein each component of the combination is provided as separate entities.

Preferably, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species, compositions, vaccines of the combination each encode a different prefusion stabilized spike protein (as defined in the first aspect). Preferably, stabilization of the perfusion conformation is obtained by introducing two consecutive proline substitutions at residues K986 and V987 in the spike protein (Amino acid positions according to reference SEQ ID NO: 1). Accordingly, in preferred embodiments, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 pre-fusion stabilized spike proteins (S_stab) each comprises at least one pre-fusion stabilizing mutation, wherein the at least one pre-fusion stabilizing mutation comprises the following amino acid substitutions: K986P and V987P (amino acid positions according to reference SEQ ID NO: 1).

Accordingly, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species, compositions, vaccines of the combination each encode a different prefusion stabilized spike protein, wherein the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more stabilized spike proteins are selected from amino acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10-26, 341-407, 609-1278, 13521-13587, 22738, 22740, 22742, 22744, 22746, 22748, 22750, 22752, 22754, 22756, 22758, 22947-2296410 or an immunogenic fragment or immunogenic variant of any of these.

In preferred embodiments, the combination comprises one nucleic acid species, composition, vaccine comprising a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 10, wherein the multivalent composition additionally comprises at least 2, 3, 4 further RNA species selected from

• i) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22961; and/or


• ii) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22960; and/or


• iii) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22963; and/or


• iv) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22941; and/or


• v) one nucleic acid species comprises a coding sequence encoding an amino acid sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22964.

Preferably, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species, composition, vaccine of the combination comprise nucleic acid coding sequences each encoding a different prefusion stabilized spike protein, wherein the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more nucleic acid coding sequences are selected from nucleic acid sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 136-138, 140-143, 145-175, 11731-11813, 11815, 11817-12050, 12052, 12054-12203, 13514, 13515, 13519, 13520, 14124-14141, 22759, 22764-22785, 22969-23184 or fragments or variants of any of these.

In preferred embodiments, the combination comprises one nucleic acid species, composition, vaccine comprising a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 137, wherein the multivalent composition additionally comprises at least 2, 3, 4 further RNA species selected from

• i) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23091; and/or


• ii) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23090; and/or


• iii) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23093; and/or


• iv) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 22999; and/or


• v) one nucleic acid species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23094.

Preferably, the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more different nucleic acid species, compositions, vaccines of the combination comprise nucleic acid coding sequences each encoding a different prefusion stabilized spike protein, wherein the at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or even more nucleic acid coding sequences are selected from RNA sequences being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 149-151, 163-165, 12338, 12541, 12810-12813, 12901, 12931, 13013, 22792, 22794, 22796, 22798, 22802, 22804, 22806, 22810, 22813, 22819, 22821, 22823, 22825, 22827, 22829, 22831, 22833, 22835, 22837, 22839, 23297-23314, 23369, 23517-23520, 23523-23525, 23527, 23529, 23530, 23589, 23737, 23957, 24397, 24837, 25057, 25277, 25717, 26925-26937149 or fragments or variants of any of these.

In preferred embodiments, the combination comprises one RNA species, compositions, vaccines comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 163, wherein the combination additionally comprises at least 2, 3, 4 further RNA species selected from

• i) one RNA species comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23311; and/or


• ii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23310; and/or


• iii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23313; and/or


• iv) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23219; and/or


• v) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23314;

wherein, preferably, each of the mRNA species comprise a Cap1 structure, and, optionally, each of the mRNA species do not comprise modified nucleotides.

In preferred embodiments, the combination comprises one RNA species, composition, vaccine comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 149 or 24837, wherein the combination additionally comprises at least 2, 3, 4 further RNA species, selected from

• i) one RNA species comprising or consisting of an RNA sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23531 or 24851; and/or


• ii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23530 or 24850; and/or


• iii) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23533 or 24853B; and/or


• iv) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23439 or 24759; and/or


• v) one RNA species comprises a coding sequence being identical or at least 70%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 23534 or 24854;

wherein, preferably, each of the mRNA species comprise a Cap1 structure, and, optionally, each of the mRNA species do not comprise modified nucleotides.

In a specific embodiment, a first component of the combination comprises a viral vector vaccine/composition, such as an adenovirus vector based vaccine, e.g., ADZ1222 or Ad26.COV-2.S, and a second component comprises a nucleic acid based vaccine/composition, preferably an mRNA-based vaccine as defined herein.

First and Second/Further Medical Use:

A further aspect relates to the first medical use of the provided nucleic acid, composition, polypeptide, vaccine, kit, or combination.

Notably, embodiments relating to the nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, and the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect, or the combination may likewise be read on and be understood as suitable embodiments of medical uses of the invention.

Accordingly, the invention provides at least one nucleic acid (e.g. DNA or RNA), preferably RNA as defined in the first aspect for use as a medicament, the composition as defined in the second aspect for use as a medicament, the polypeptide as defined in the third aspect for use as a medicament, the vaccine as defined in the fourth aspect for use as a medicament, and the kit or kit of parts as defined in the fifth aspect for use as a medicament, and the combination.

The present invention furthermore provides several applications and uses of the nucleic acid, composition, polypeptide, vaccine, or kit, or combination.

In particular, nucleic acid (preferably RNA), composition, polypeptide, vaccine, or kit, or combination may be used for human medical purposes and also for veterinary medical purposes, preferably for human medical purposes.

In particular, nucleic acid (preferably RNA), composition, polypeptide, vaccine, or kit or kit of parts or combination is for use as a medicament for human medical purposes, wherein said nucleic acid (preferably RNA), composition, polypeptide, vaccine, or kit or kit of parts may be suitable for young infants, newborns, immunocompromised recipients, as well as pregnant and breast-feeding women and elderly people. In particular, nucleic acid (preferably RNA), composition, polypeptide, vaccine, or kit or kit of parts is for use as a medicament for human medical purposes, wherein said nucleic acid (preferably RNA), composition, polypeptide, vaccine, or kit or kit of parts is particularly suitable for elderly human subjects.

Said nucleic acid (preferably RNA), composition, polypeptide, vaccine, or kit or combination is for use as a medicament for human medical purposes, wherein said RNA, composition, vaccine, or the kit or kit of parts may be particularly suitable for intramuscular injection or intradermal injection.

In yet another aspect, the invention relates to the second medical use of the provided nucleic acid, composition, polypeptide, vaccine, or kit or combination.

Accordingly, the invention provides at least one nucleic acid, preferably RNA as defined in the first aspect for treatment or prophylaxis of an infection with a coronavirus, preferably SARS-CoV-2 coronavirus, or a disorder or a disease related to such an infection, such as COVID-19; a composition as defined in the second aspect for treatment or prophylaxis of an infection with a coronavirus, preferably SARS-CoV-2 coronavirus, or a disorder or a disease related to such an infection, such as COVID-19; a polypeptide as defined in the third aspect for treatment or prophylaxis of an infection with a coronavirus, preferably SARS-CoV-2 coronavirus, or a disorder or a disease related to such an infection, such as COVID-19; a vaccine as defined in the fourth aspect for treatment or prophylaxis of an infection with a coronavirus, preferably SARS-CoV-2 coronavirus, or a disorder or a disease related to such an infection, such as COVID-19; a kit or kit of parts as defined in the fifth aspect for treatment or prophylaxis of an infection with a coronavirus, preferably SARS-CoV-2 coronavirus, or a disorder or a disease related to such an infection, such as COVID-19; a combination as defined in the sixth aspect for treatment or prophylaxis of an infection with a coronavirus, preferably SARS-CoV-2 coronavirus, or a disorder or a disease related to such an infection, such as COVID-19.

In embodiments, the nucleic acid, preferably RNA of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect, or the combination of the sixth aspect, is for use in the treatment or prophylaxis of an infection with a coronavirus, preferably with SARS-CoV-2 coronavirus.

Particularly, the nucleic acid, preferably RNA of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect, or the combination of the sixth aspect, may be used in a method of prophylactic (pre-exposure prophylaxis or post-exposure prophylaxis) and/or therapeutic treatment of infections caused by a coronavirus, preferably SARS-CoV-2 coronavirus.

Particularly, the nucleic acid, preferably RNA of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect, or the combination of the sixth aspect, may be used in a method of prophylactic (pre-exposure prophylaxis or post-exposure prophylaxis) and/or therapeutic treatment of COVID-19 disease caused by a SARS-CoV-2 coronavirus infection.

The nucleic acid, the composition, the polypeptide, or the vaccine, or the combination may preferably be administered locally. In particular, composition or polypeptides or vaccines or combinations may be administered by an intradermal, subcutaneous, intranasal, or intramuscular route. In embodiments, the inventive nucleic acid, composition, polypeptide, vaccine may be administered by conventional needle injection or needle-free jet injection. Preferred in that context is intramuscular injection.

In embodiments where plasmid DNA is used and comprised in the composition or vaccine or combination, the composition/vaccine/combination may be administered by electroporation using an electroporation device, e.g. an electroporation device for intradermal or intramuscular delivery. Suitably, a device as described in U.S. Pat. No. 7,245,963B2 may be used, in particular a device as defined by claims 1 to 68 of U.S. Pat. No. 7,245,963B2.

In embodiments where adenovirus DNA is used and comprised in the composition or vaccine or combination, the composition/vaccine/combination may be administered by intranasal administration.

In embodiments, the nucleic acid as comprised in a composition or vaccine or combination as defined herein is provided in an amount of about 100 ng to about 500 ug, in an amount of about 1 ug to about 200 ug, in an amount of about 1 ug to about 100 ug, in an amount of about 5 ug to about 100 ug, preferably in an amount of about 10 ug to about 50 ug, specifically, in an amount of about 1 ug, 2 ug, 3 ug, 4 ug, 5 ug, 8 ug, 9 ug, 10 ug, 11 ug, 12 ug, 13 ug, 14 ug, 15 ug, 16 ug 20 ug, 25 ug, 30 ug, 35 ug, 40 ug, 45 ug, 50 ug, 55 ug, 60 ug, 65 ug, 70 ug, 75 ug, 80 ug, 85 ug, 90 ug, 95 ug or 100 ug.

In some embodiments, the vaccine comprising the nucleic acid, or the composition comprising the nucleic acid is formulated in an effective amount to produce an antigen specific immune response in a subject. In some embodiments, the effective amount of nucleic acid is a total dose of 1 ug to 200 ug, 1 ug to 100 ug, or 5 ug to 100 ug.

In embodiments where the nucleic acid is provided in a lipid-based carrier, e.g. an LNP, the amount of PEG-lipid as defined herein comprised in one dose is lower than about 50 μg PEG lipid, preferably lower than about 45 μg PEG lipid, more preferably lower than about 40 μg PEG lipid.

Having a low amount of PEG lipid in one dose may reduce the risk of adverse effects (e.g. allergies).

In particularly preferred embodiments, the amount of PEG-lipid comprised in one dose is in a range from about 3.5 μg PEG lipid to about 35 μg PEG lipid.

In embodiments where the nucleic acid is provided in a lipid-based carrier, e.g. an LNP, the amount of cationic lipid as defined herein comprised in one dose is lower than about 400 μg cationic lipid, preferably lower than about 350 μg cationic lipid, more preferably lower than about 300 μg cationic lipid.

Having a low amount of cationic lipid in one dose may reduce the risk of adverse effects (e.g. fewer).

In particularly preferred embodiments, the amount of cationic-lipid comprised in one dose is in a range from about 30 μg PEG lipid to about 300 μg PEG lipid.

In one embodiment, the immunization protocol for the treatment or prophylaxis of a subject against coronavirus, preferably SARS-CoV-2 coronavirus comprises one single doses of the composition or the vaccine.

In some embodiments, the effective amount is a dose of 1 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 2 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 3 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 4 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 5 ug administered to the subject in one vaccination. 6 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 7 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 8 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 9 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 10 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 11 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 12 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 13 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 14 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 16 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 20 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 25 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 30 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 40 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 50 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 100 ug administered to the subject in one vaccination. In some embodiments, the effective amount is a dose of 200 ug administered to the subject in one vaccination. A “dose” in that context relates to the effective amount of nucleic acid, preferably mRNA as defined herein.

In preferred embodiments, the immunization protocol for the treatment or prophylaxis of a coronavirus, preferably a SARS-CoV-2 coronavirus infection comprises a series of single doses or dosages of the composition or the vaccine. A single dosage, as used herein, refers to the initial/first dose, a second dose or any further doses, respectively, which are preferably administered in order to “boost” the immune reaction.

In some embodiments, the effective amount is a dose of 1 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 2 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 3 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 4 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 5 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 6 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 7 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 8 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 9 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 10 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 11 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 12 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 13 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 14 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 16 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 20 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 25 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 30 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 40 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 50 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 100 ug administered to the subject a total of two times. In some embodiments, the effective amount is a dose of 200 ug administered to the subject a total of two times. A “dose” in that context relates to the effective amount of nucleic acid, preferably mRNA as defined herein.

In preferred embodiments, the vaccine/composition/combination immunizes the subject against a coronavirus, preferably against a SARS-CoV-2 coronavirus infection (upon administration as defined herein) for at least 1 year, preferably at least 2 years. In preferred embodiments, the vaccine/composition/combination immunizes the subject against a coronavirus, preferably against a SARS-CoV-2 coronavirus for more than 2 years, more preferably for more than 3 years, even more preferably for more than 4 years, even more preferably for more than 5-10 years.

Method of Treatment and Use, Diagnostic Method and Use:

In another aspect, the present invention relates to a method of treating or preventing a disorder.

Notably, embodiments relating to the nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, and the vaccine of the fourth aspect, the kit or kit of parts of the fifth aspect, the combination of the sixth aspect, or medical uses may likewise be read on and be understood as suitable embodiments of methods of treatments as provided herein. Furthermore, specific features and embodiments relating to method of treatments as provided herein may also apply for medical uses of the invention.

Preventing (Inhibiting) or treating a disease, in particular a coronavirus infection relates to inhibiting the full development of a disease or condition, for example, in a subject who is at risk for a disease such as a coronavirus infection. “Treatment” refers to a therapeutic intervention that ameliorates a sign or symptom of a disease or pathological condition after it has begun to develop. The term “ameliorating”, with reference to a disease or pathological condition, refers to any observable beneficial effect of the treatment. Inhibiting a disease can include preventing or reducing the risk of the disease, such as preventing or reducing the risk of viral infection. The beneficial effect can be evidenced, for example, by a delayed onset of clinical symptoms of the disease in a susceptible subject, a reduction in severity of some or all clinical symptoms of the disease, a slower progression of the disease, a reduction in the viral load, an improvement in the overall health or well-being of the subject, or by other parameters that are specific to the particular disease. A “prophylactic” treatment is a treatment administered to a subject who does not exhibit signs of a disease or exhibits only early signs for the purpose of decreasing the risk of developing pathology.

In preferred embodiments, the present invention relates to a method of treating or preventing a disorder, wherein the method comprises applying or administering to a subject in need thereof at least one nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect, or the combination of the sixth aspect.

In preferred embodiments, the disorder is an infection with a coronavirus, or a disorder related to such infections, in particular an infection with SARS-CoV-2 coronavirus, or a disorder related to such infections, e.g. COVID-19.

In preferred embodiments, the present invention relates to a method of treating or preventing a disorder as defined above, wherein the method comprises applying or administering to a subject in need thereof at least one nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect, or the combination of the sixth aspect, wherein the subject in need is preferably a mammalian subject.

In certain embodiments, a method of treating or preventing disease by applying or administering to a subject in need thereof at least one nucleic acid of the first aspect, the composition of the second aspect, the polypeptide of the third aspect, the vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect or the combination of the sixth aspect, is further defined as a method of reducing disease burden in the subject. For example, the method preferably reduces the severity and/or duration of one or more symptom of COVID-19 disease. In some aspects, a method reduces the probability that a subject will require hospital admission, intensive care unit admission, treatment with supplemental oxygen and/or treatment with a ventilator. In further aspects, the method reduces the probability that a subject will develop a fever, breathing difficulties; loss of smell and/or loss of taste. In preferred aspects, the method reduces the probability that a subject will develop severe or moderate COVID-19 disease. In certain aspects, a method of the embodiments prevents severe or moderate COVID-19 disease in the subject between about 2 weeks and 1 month, 2 months, 3 months, 4 months, 5 months, 6 months, 1 year or 2 years after the subject is administered a composition of the embodiments. In preferred aspects, a method of the embodiments prevents symptomatic COVID-19 disease. In further aspects, a method of the embodiment prevents detectable levels of SARS CoV-2 nucleic acid in the subject between about 2 weeks and 1 month, 2 months, 3 months, 4 months, 5 months, 6 months, 1 year or 2 years after the subject is administered a composition of the embodiments. In further aspects, a method of the embodiments is defined as a method for providing protective immunity to a coronavirus infection (e.g., SARS CoV-2 infection) in the subject. In still further aspects, a method of the embodiments prevents moderate and severe COVID-19 disease in at least 80%, 85%, 90% or 95% of treated subjects. In yet further aspects, a method of the embodiments prevents moderate and severe COVID-19 disease in at least 80%, 85%, 90% or 95% of treated subjects from about 2 weeks to about 1 year after administering the second or subsequent immunogenic composition (e.g., a booster administration). In yet further aspects, a method of the embodiments prevents moderate and severe COVID-19 disease in at least 80%, 85%, 90% or 95% of treated subjects from about 2 weeks to about 3 month, 6 months, 9 months, 1 year, 1.5 years, 2 years or 3 years after administering the second or subsequent composition.

In a further aspects, a method of the embodiments comprises (i) obtaining a composition (e.g., a vaccine composition) of the embodiments, wherein the composition is lyophilized; (ii) solubilizing the lyophilized composition in a pharmaceutically acceptable liquid carrier to produce a liquid composition; and (iii) administering an effective amount of the liquid composition to the subject. In some aspects, the lyophilized composition comprises less than about 10% water content. For example, the lyophilized composition can preferably comprise about 0.1% to about 10%, 0.5% to 7.5% or 0.5% to 5.0% water.

In still further aspects, a method of the embodiments comprises administering a vaccine composition comprising a mRNA at least about 95% identical to SEQ ID NO: 163 (e.g., in complex with a LNP) to a subject. In further aspects, a method of the embodiments comprises administering a vaccine composition comprising a mRNA at least about 95% identical to SEQ ID NO: 149, 24837, 23311, 23531, 23310, 23530, 23313, or 23533 (e.g., in complex with a LNP) to a subject. In some aspects, such a method provides a sufficient immune response in the subject to protect the subject from severe COVID-19 disease for at least about 6 months. For example, in some aspects, the subject is protected from severe COVID-19 disease for about 6 months to about 1 year, 1.5 years, 2 years, 2.5 years, 3 years, 4 years or 5 years. Thus, in some aspects, a method of the embodiments provides a single dose vaccine composition that can provide prolonged (e.g., greater than 6 months of) protection from severe disease to a subject.

As used herein severe COVID-19 disease is defined as a subject experiencing one or more of the following:

• 
  
  
  
  • Clinical signs at rest indicative of severe systemic illness (respiratory rate ≥30 breaths per minute, heart rate ≥125 per minute, SpO2≤93% on room air at sea level or PaO2/FIO2<300 mm Hg (adjusted according to altitude))
  
  
  • Respiratory failure (defined as needing high flow-oxygen, noninvasive ventilation, mechanical ventilation or ECMO)
  
  
  • Evidence of shock (SBP <90 mm Hg, DBP <60 mmHg, or requiring vasopressors)
  
  
  • Significant renal, hepatic, or neurologic dysfunction
  
  
  • Admission to ICU
  
  
  • Death
  
  
  
  

As used herein moderate COVID-19 disease is defined as a subject experiencing one or more of the following:

• 
  
  
  
  • Shortness of breath or difficulty breathing
  
  
  • Respiratory rate ≥20 breaths per minute
  
  
  • Abnormal SpO2 but still >93% on room air at sea level (adjusted according to altitude)
  
  
  • Clinical or radiographic evidence of lower respiratory tract disease
  
  
  • Radiologic evidence of deep vein thrombosis (DVT)
  
  
  
  

As used herein mild COVID-19 disease is defined as a subject experiencing all of the following:

• 
  
  
  
  • Symptomatic AND
  
  
  • No shortness of breath or difficulty breathing AND
  
  
  • No hypoxemia (adjusted according to altitude) AND
  
  
  • Does not meet the case definition of moderate or severe COVID-19 disease
  
  
  
  

In particularly preferred embodiments, the subject in need is a mammalian subject, preferably a human subject, e.g. newborn, pregnant, immunocompromised, and/or elderly. In some embodiments, the subject between the ages of 6 months and 100 years, 6 months and 80 years, 1 year and 80 years, 1 year and 70 years, 2 years and 80 years or 2 years and 60 years. In other embodiments the subject is a newborn or infant of an age of not more than 3 years, of not more than 2 years, of not more than 1.5 years, of not more than 1 year (12 months), of not more than 9 months, 6 months or 3 months. In some other embodiments the subject is an elderly subject of an age of at least 50, 60, 65, or 70 years. In further aspects, a subject for treatment according to the embodiments is 61 years of age or older. In still further aspects, the subject is 18 years old to 60 years old.

In certain embodiments, a subject for treatment according to the embodiments is a pregnant subject, such a pregnant human. In some aspects, the subject has been pregnant for more than about one month, two months, three months, four months, five months, six months, seven months or eight months.

In particularly preferred embodiments, the human subject is an elderly human subject.

In certain aspects, a subject for treatment according to the embodiments has native American, African, Asian or European heritage. In some aspects, the subject has at least about 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% or 90% native American, African, Asian or European heritage. In certain aspects, the subject has native American heritage, such as at least about 10%, 25% or 50% native American heritage. In further aspects, the subject is an elderly subject having native American heritage, e.g., a subject who is at least 55, 60, 65 or 70 years of age.

In further aspects, a subject for treatment according to the embodiments has a disease or is immune compromised. In some aspects, the subject has liver disease, kidney disease diabetes, hypertension, heart disease or lung disease. In further aspects, a subject for treatment according to the embodiments is a subject with history of allergic reaction, such a subject having food allergies. In some aspect, the subject has had a previous allergic reaction to a vaccine, such as an anaphylactic reaction. In still further aspects, a subject for treatment according to the methods is a subject having detectable anti-PEG antibodies, such as detectable anti-PEG IgE in the serum.

In further aspects, a subject for treatment according to the embodiments has at least one co-morbidity selected from:

(i) Chronic kidney disease: Kidney function will be ascertained from the serum creatinine measurement within the last 3-6 months, converted into estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, with impaired kidney function defined as eGFR <60 mL/min/1.73 m².

• 
  
  
  
  • Mild chronic kidney disease is defined as an eGFR between 60 89 mL/min/1.73 m2.
  
  
  • Moderate chronic kidney disease is defined as an eGFR between 31-59 mL/min/1.73 m2 with stable therapy and good maintenance over at least 6 months (modified from Clinical Practice Clinical Guidelines for Chronic Kidney Disease: Am J Kidney Dis, 2002).
  
  
  
  

(ii) COPD (including emphysema and chronic bronchitis).

• 
  
  
  
  • Mild COPD with or without cough or sputum production is defined as forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) <0.7 and FEV1 ≥80%, predicted.
  
  
  • Moderate COPD with or without cough or sputum production is defined as FEV1/FVC <0.7 and FEV1 ≥50%, but <80% predicted with stable treatment (GOLD Criteria for COPD severity).
  
  
  
  

(iii) Obesity with body mass index (BMI) of >32 kg/m²—any extreme morbid obesity will also be included.

(iv) Chronic cardiovascular conditions (heart failure, coronary artery disease, cardiomyopathies, arterial hypertension), including the following:

• 
  
  
  
  • Class I heart failure with potential high risk for developing heart failure in future with no functional or structural heart disorder.
  
  
  • Class II heart failure: subjects with cardiac disease resulting in slight limitation of physical activity. Comfortable at rest.
  
  
  • Ordinary physical activity results in fatigue, palpitation, dyspnea, or anginal pain.
  
  
  • Class III heart failure with marked limitation of physical activity, but comfortable at rest but less than ordinary activity results in symptoms.
  
  
  • A structural heart disorder without symptoms at any stage.
  
  
  • Mild left ventricular systolic or diastolic dysfunction, usually with not much produced clinical signs.
  
  
  • Moderate left ventricular failure with exertional dyspnea or orthopnea or paroxysmal nocturnal dyspnea as per New York Heart Association (NYHA), stable with medication (Class
  
  
  • Coronary artery disease of 2 and above metabolic equivalent threshold (MET) up to moderate, stable with medication. (MET is defined as the amount of oxygen consumed while sitting at rest and is equal to 3.5 ml O₂ per kg body weight×min; 4 Normal, can climb a flight of stairs or walk up a hill and can participate in other strenuous activities; 1 can take care of him/herself and may not maintain themselves and gets constraints on exertion.)
  
  
  • Cardiomyopathies of non-infective and metabolic origin of 2-3 MET with medication.
  
  
  • Stage 1 hypertension or Stage 2 hypertension stable and controlled with medications.
  
  
  
  

(v) Chronic HIV infection with stable aviraemia (<50 copies/mL) and CD4 count >350/mL as documented by blood samples taken within 12 months before enrolment. (Viral load <50 copies/mL with transient changes of 50-350 copies/mL is allowed.)

(vi) Type 2 diabetes mellitus, either controlled with medication [hemoglobin A1c (HbA1c)<58 mmol/mol (7.45%)] or uncontrolled with recent HbA1c of >58 mmol/mol (7.45%); [(HbA1c in %−2.15)×10.929=HbA1c in mmol/mol]; in uncontrolled DM HbA1c should be within <10% variation and should not have any history of diabetic ketoacidosis or episode of severe symptomatic hypoglycemia within prior 3 months.

(vii) Subjects who underwent renal transplant at least a year ago under stable conditions for at least 6 months with medications, categorized as low risk of rejection.

In still further aspects, a subject for treatment according to the embodiments has not been treated with an immunosuppressant drug for more than 14 days in the last 6 months. In some aspects, a subject for treatment according to the embodiments has not received a live vaccine for at least 28 days prior to the administration and/or has not received an inactivated vaccine for at least 14 days prior to the administration. In further aspects a subject for treatment according to the embodiments has NOT:

• 
  
  
  
  • Had virologically-confirmed COVID-19 illness;
  
  
  • For females: experienced pregnancy or lactation with-in a month prior to administration of the composition of the embodiments;
  
  
  • had treatment with an investigational or non-registered product (e.g., vaccine or drug) within 28 days preceding the administration of the composition of the embodiments;
  
  
  • received a licensed vaccines within 28 days (for live vaccines) or 14 days (for inactivated vaccines) prior to the administration of the composition of the embodiments;
  
  
  • been previously or concurrently treated with any investigational SARS-CoV-2 vaccine or another coronavirus (SARS-CoV, MERS-CoV) vaccine;
  
  
  • been treated with immunosuppressants or other immune-modifying drugs (e.g., corticosteroids, biologicals and methotrexate) for >14 days total within 6 months preceding the administration of the composition of the embodiments;
  
  
  • had any medically diagnosed or suspected immunosuppressive or immunodeficient condition based on medical history and physical examination including known infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV); current diagnosis of or treatment for cancer including leukemia, lymphoma, Hodgkin disease, multiple myeloma, or generalized malignancy; chronic renal failure or nephrotic syndrome; and receipt of an organ or bone marrow transplant.
  
  
  • had a history of angioedema (hereditary or idiopathic), or history of any anaphylactic reaction or pIMD.
  
  
  • a history of allergy to any component of CVnCoV vaccine.
  
  
  • been administered of immunoglobulins or any blood products within 3 months prior to the administration of the composition of the embodiments;
  
  
  • experienced a significant acute or chronic medical or psychiatric illness; and/or
  
  
  • experienced severe and/or uncontrolled cardiovascular disease, gastrointestinal disease, liver disease, renal disease, respiratory disease, endocrine disorder, and neurological and psychiatric illnesses.
  
  
  
  

In certain aspects, a subject for treatment according to the methods of the embodiments does not have any potential immune-mediated disease (pIMD). In further aspects, a treatment method of the embodiments does not induce any pIMD in a treated subject. As used herein pIMDs are defined as Celiac disease; Crohn's disease; Ulcerative colitis; Ulcerative proctitis; Autoimmune cholangitis; Autoimmune hepatitis; Primary biliary cirrhosis; Primary sclerosing cholangitis; Addison's disease; Autoimmune thyroiditis (including Hashimoto thyroiditis; Diabetes mellitus type I; Grave's or Basedow's disease; Antisynthetase syndrome; Dermatomyositis; Juvenile chronic arthritis (including Still's disease); Mixed connective tissue disorder; Polymyalgia rheumatic; Polymyositis; Psoriatic arthropathy; Relapsing polychondritis; Rheumatoid arthritis; Scleroderma, (e.g., including diffuse systemic form and CREST syndrome); Spondyloarthritis, (e.g., including ankylosing spondylitis, reactive arthritis (Reiter's Syndrome) and undifferentiated spondyloarthritis); Systemic lupus erythematosus; Systemic sclerosis; Acute disseminated encephalomyelitis, (including site specific variants (e.g., non-infectious encephalitis, encephalomyelitis, myelitis, myeloradiculomyelitis)); Cranial nerve disorders, (e.g., including paralyses/paresis (e.g., Bell's palsy)); Guillain-Barré syndrome, (e.g., including Miller Fisher syndrome and other variants); Immune-mediated peripheral neuropathies, Parsonage-Turner syndrome and plexopathies, (e.g., including chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, and polyneuropathies associated with monoclonal gammopathy); Multiple sclerosis; Narcolepsy; Optic neuritis; Transverse Myelitis; Alopecia areata; Autoimmune bullous skin diseases, including pemphigus, pemphigoid and dermatitis herpetiformis; Cutaneous lupus erythematosus; Erythema nodosum; Morphoea; Lichen planus; Psoriasis; Sweet's syndrome; Vitiligo; Large vessels vasculitis (e.g., including: giant cell arteritis such as Takayasu's arteritis and temporal arteritis); Medium sized and/or small vessels vasculitis (e.g., including: polyarteritis nodosa, Kawasaki's disease, microscopic polyangiitis, Wegener's granulomatosis, Churg-Strauss syndrome (allergic granulomatous angiitis), Buerger's disease thromboangiitis obliterans, necrotizing vasculitis and anti-neutrophil cytoplasmic antibody (ANCA) positive vasculitis (type unspecified), Henoch-Schonlein purpura, Behcet's syndrome, leukocytoclastic vasculitis); Antiphospholipid syndrome; Autoimmune hemolytic anemia; Autoimmune glomerulonephritis (including IgA nephropathy, glomerulonephritis rapidly progressive, membranous glomerulonephritis, membranoproliferative glomerulonephritis, and mesangioproliferative glomerulonephritis); Autoimmune myocarditis/cardiomyopathy; Autoimmune thrombocytopenia; Goodpasture syndrome; Idiopathic pulmonary fibrosis; Pernicious anemia; Raynaud's phenomenon; Sarcoidosis; Sjögren's syndrome; Stevens-Johnson syndrome; Uveitis).

In certain aspects, a vaccination method of the embodiments does not result in a subject experiencing any adverse events of special interest (AESIs). As used herein AESIs are defined as a pIMD listed above; Anaphylaxis; Vasculitides; Enhanced disease following immunization; Multisystem inflammatory syndrome in children; Acute Respiratory Distress Syndrome; COVID-19 disease; Acute cardiac injury; Microangiopathy; Heart failure and cardiogenic shock; Stress cardiomyopathy; Coronary artery disease; Arrhythmia; Myocarditis, pericarditis; Thrombocytopenia; Deep vein thrombosis; Pulmonary embolus; Cerebrovascular stroke; Limb ischemia; Hemorrhagic disease; Acute kidney injury; Liver injury; Generalized convulsion; Guillain-Barré Syndrome; Acute disseminated encephalomyelitis; Anosmia, ageusia; Meningoencephalitis; Chilblain-like lesions; Single organ cutaneous vasculitis; Erythema multiforme; Serious local/systemic AR following immunization

In particular, such the method of treatment may comprise the steps of:

• a) providing at least one nucleic acid (e.g. DNA or RNA), preferably at least one RNA of the first aspect, at least one composition of the second aspect, at least one polypeptide of the third aspect, at least one vaccine of the fourth aspect, or the kit or kit of parts of the fifth aspect;


• b) applying or administering said nucleic acid, composition, polypeptide, vaccine, or kit or kit of parts to a subject as a first dose


• c) optionally, applying or administering said nucleic acid, composition, polypeptide, vaccine, or kit or kit of parts to a subject as a second dose or a further dose, preferably at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, months after the first dose.

The first dosage, as used herein, refers to the initial/first dose, a second dose or any further doses, respectively, which are preferably administered in order to “boost” the immune reaction. In certain aspects, the vaccine/composition is administered to a subject one, two three, four or more times. In some aspects, the vaccine/composition is administered to the subject at least first and a second time (e.g., a prime and boost). I some aspects, the send administration is at least 10 days, 14 days, 21 days, 28 days, 35 days, 42 days, 49 days or 56 days after the first administration. In some aspects, the time between the first administration and the second administration is between about 7 days and about 56 days; about 14 days and about 56 days; about 21 days and about 56 days; or about 28 days and about 56 days. In further aspects, the vaccine/composition is administered to a subject three or more times. In certain aspects, there is at least 10 days, 14 days, 21 days, 28 days, 35 days, 42 days, 49 days or 56 days between each administration of the vaccine/composition.

In some aspects, a subject for treatment according to the embodiments was previously infected with SARS CoV-2 or was previously treated with at least a first SARS CoV-2 vaccine composition. In some aspects, the subject was treated with one, two, three or more doses of a first SARS CoV-2 vaccine composition. In some aspects, the composition of the embodiments used to treat a subject is a different type of vaccine composition than the composition previously used to treat the subject. In some aspects, the subject was previously treated with a mRNA vaccine, such as BNT162 or mRNA-1273. In further aspects, the subject was previously treated with a protein subunit vaccine, such as spike protein based vaccine, e.g., NVX-CoV2373 or COVAX. In certain preferred aspects, protein subunit vaccine compositions comprise an adjuvant. In further aspects, the subject was previously treated with a viral vector vaccine, such as an adenovirus vector based vaccine, e.g., ADZ1222 or Ad26.COV-2.S. In still further aspects, the subject was previously treated with an inactivated virus vaccine to SARS CoV-2 such as CoronaVac, BBIBP-CorV or BBV152. In further aspects, a subject previously treated with a vaccine composition has detectable SARS CoV-2 binding antibodies, such as SARS CoV-2 S protein-binding antibodies or SARS CoV-2 N protein-binding antibodies. In further aspects, a subject for treatment according the embodiments was treated with a first SARS CoV-2 vaccine composition at least about 3 month, 6 months, 9 months, 1 year, 1.5 years, 2 years or 3 years ago. In still further aspects, a subject for treatment according the embodiments was treated with a first SARS CoV-2 vaccine composition between about 3 months and 2 years ago or between about 6 months and 2 years ago. In some aspects, a subjects treated with a further vaccine composition of the embodiments are protected from moderate and severe COVID-19 disease in at least 80%, 85%, 90% or 95% of treated subjects. For example, the treated subjects can be protected from moderate and severe COVID-19 disease in at least 80%, 85%, 90% or 95% of treated subjects from about 2 weeks to about 1 year after administration of the further composition. In still further aspects, administering the further vaccine composition of the embodiments prevents moderate and severe COVID-19 disease in at least 80%, 85%, 90% or 95% of treated subjects from about 2 weeks to about 3 month, 6 months, 9 months, 1 year, 1.5 years, 2 years or 3 years after said administration. Examples of such combination vaccination strategies are shown below:

Dose 1 mRNA vaccine-T1-dose 2 mRNA vaccine-T2-dose 3 mRNA vaccine

Dose 1 mRNA vaccine-T1-dose 2 mRNA vaccine-T2-dose 3 protein subunit vaccine

Dose 1 mRNA vaccine-T1-dose 2 mRNA vaccine-T2-dose 3 viral vector vaccine

Dose 1 mRNA vaccine-T1-dose 2 mRNA vaccine-T2-dose 3 inactivated virus vaccine

Dose 1 protein subunit vaccine-T1-dose 2 protein subunit vaccine-T2-dose 3 mRNA vaccine

Dose 1 inactivated virus vaccine-T1-dose 2 inactivated virus vaccine-T2-dose 3 mRNA vaccine

Dose 1 viral vector vaccine-T1-dose 2 viral vector vaccine-T2-dose 3 mRNA vaccine

Dose 1 viral vector vaccine-T2-dose 2 mRNA vaccine

Dose 1 protein subunit vaccine-T2-dose 2 mRNA vaccine

Dose 1 inactivated virus vaccine-T2-dose 2 mRNA vaccine

Dose 1 mRNA vaccine-T2-dose 2 mRNA vaccine

In the examples, above time period 1 (T1) is typically 2 to 6 weeks, preferably 3 to 4 weeks. Time period 2 (T2) is in some cases, about 3 months, 6 months, 9 months, 1 year, 1.5 years, 2 years or three years.

In some aspects, a method of the embodiments comprises administering multiple doses of a vaccine composition to a subject. In a further aspect, there is provided a method of reducing reactogenicity of a SARS CoV-2 booster vaccine composition. In some aspects, after an initial vaccination, subject exhibiting a high level of reactogenicity are administered a booster vaccine that is different from the initial vaccine composition. For example, in some aspects, the initial vaccine is BNT162 or mRNA-1273 and the booster vaccine is a mRNA vaccine composition of the embodiments. In some aspects, a booster vaccine composition for a subject with high reactogenicity is selected based having a lower concentration of PEG or PEG-conjugate compared to the previously administered vaccine composition. In some aspects, a booster vaccine composition for a subject with high reactogenicity is selected based on a lower concentration of mRNA or LNP compared to the previously administered vaccine composition.

In certain aspects, a subject for treatment according to the embodiments is administered a vaccine composition as booster vaccine and has previously been treated with one or more administrations of a coronavirus vaccine composition. In certain aspects, the subject being treated with a booster vaccine previously was treated with a vaccine composition that included a spike protein antigen or a nucleic acid molecule encoding a spike protein antigen. In some aspects, the subject selected for treatment with the booster vaccine was previously administered a vaccine composition comprising, or encoding, a spike protein having a different amino acid sequence than the spike protein of the booster vaccine. In certain aspects, the previously administered vaccine composition comprised, or encoded, a spike (e.g., a SARS CoV-2 spike) protein having at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid differences relative to the booster vaccine composition. In certain aspects, the booster vaccine composition comprises a RNA encoding a spike protein having about 1 to 50; about 3 to 30; about 5 to 30 or about 10 to 25 amino acid differences relative to the previously administered vaccine composition. In still further aspects, the booster vaccine composition comprises RNA encoding 2, 3, 4 or more distinct spike proteins with different amino acid sequences.

In further aspects, methods of the embodiments comprise administering 2 or more booster vaccine compositions to a subject, wherein each booster vaccine composition comprises RNA encoding a distinct spike protein with different amino acid sequences. In some aspects, such distinct booster vaccine compositions are administered essentially simultaneously or less than about 10 minutes, 20 minutes, 30 minutes, 1 hour or 2 hours apart. In some aspects, distinct booster vaccine compositions are administered to the same site, such as intramuscular injections to the same arm of the subject. In further aspects, distinct booster vaccine compositions are administered to different sites, such as intramuscular injections to different arms or to one or both arms and one more leg muscles.

In certain aspects, a method of the embodiments is further defined as a method of stimulating an antibody or CD8+ T-cell response in a subject. In some aspects, the method is defined as a method of stimulating a neutralizing antibody response in a subject. In further aspects, the method is defined as a method of stimulating a protective immune response in a subject. In yet further aspects, the method is defined as a method of stimulating TH2 directed immune response in a subject.

In further aspects, administration of a vaccine/composition/combination of the embodiments stimulates an antibody response that produces between about 10 and about 500 coronavirus spike protein-binding antibodies for every coronavirus neutralizing antibody in the subject. For example, the administration can stimulate an antibody response that produces no more than about 200 spike protein-binding antibodies for every coronavirus neutralizing antibody. In further aspects, the administration stimulates an antibody response that produces between about 10 and about 300; about 20 and about 300; about 20 and about 200; about 30 and about 100; or about 30 and about 80 coronavirus spike protein-binding antibodies for every coronavirus neutralizing antibody. In still further aspects, administration of composition of the embodiments stimulates an antibody response in a subject that includes a ratio of spike protein-binding antibodies to coronavirus neutralizing antibodies that is with 20%, 15%, 10% or 5% of the ratio of spike protein-binding antibodies to coronavirus neutralizing antibodies found in average convalescent patient serum (from a subject who has recovered from coronavirus infection).

In yet further aspects, administration of a vaccine/composition/combination of the embodiments stimulates an antibody response that produces between about 1 and about 500 coronavirus spike protein receptor binding domain (RBD)-binding antibodies for every coronavirus neutralizing antibody in the subject. In further aspects, the administration stimulates an antibody response that produces no more than about 50 spike protein RBD-binding antibodies for every coronavirus neutralizing antibody. In still further aspects, administration stimulates an antibody response that produces between about 1 and about 200; about 2 and about 100; about 3 and about 200; about 5 and about 100; about 5 and about 50; or about 5 and about 20 spike protein RBD-binding antibodies for every coronavirus neutralizing antibody. In still further aspects, administration of composition of the embodiments stimulates an antibody response in a subject that includes a ratio of spike protein RBD-binding antibodies to coronavirus neutralizing antibodies that is with 20%, 15%, 10% or 5% of the ratio of spike protein RBD-binding antibodies to coronavirus neutralizing antibodies found in average convalescent patient serum (from a subject who has recovered from coronavirus infection).

In still further aspects, administration of a vaccine/composition/combination of the embodiments induces essentially no increase in IL-4, IL-13, TNF and/or IL-1β in the subject. In further aspects, the administration of a vaccine/composition of the embodiments induces essentially no increase in serum IL-4, IL-13, TNF and/or IL-1β in the subject. In some aspects, the administration of a vaccine/composition of the embodiments induces essentially no increase in IL-4, IL-13, TNF and/or IL-1β at the injection site (e.g., an intramuscular injection site) in the subject. In still further aspects, a method of the embodiments comprises administration of a vaccine/composition of the embodiments to a human subject having a disease. In certain aspects, the subject has cardiovascular disease, kidney disease, lung disease or an autoimmune disease. In some aspects, a vaccine/composition of the embodiments is administered to a subject who is receiving anti-coagulation therapy.

In still further aspects, administering a vaccine/composition/combination of the embodiments to human subjects results in no more than 20%, 15%, 10% 7.5% or 5% of the subjects experiencing a Grade 3 local adverse event (see Table A below). For example, in some aspects, no more than 10% of subjects experience a Grade 3 local adverse event after a first or a second dose of the composition. In preferred aspects, administering a composition of the embodiments to human subjects results in no more than 40%, 30%, 25%, 20%, 15%, 10%, 7.5% or 5% of the subjects experiencing a Grade 2 of higher local adverse event. For example, in some aspects, no more than 30% of subjects experience a Grade 2 or higher local adverse event after a first or a second dose of the composition. In some aspects, administering a composition of the embodiments to human subjects results in no more than 10% of the subjects experiencing Grade 3 pain, redness, swelling and/or itching at the injection site

In further aspects, administering a vaccine/composition/combination of the embodiments to human subjects results in no more than 30%, 25%, 20%, 15%, 10% or 5% of the subjects experiencing a Grade 3 systemic adverse event (see Table B below). For example, in some aspects, no more than 25% of subjects experience a Grade 3 systemic adverse event after a first dose of the composition. In some aspects, no more than 40% of subjects experience a Grade 3 systemic adverse event after a second dose of the composition. In some aspects, administering a composition of the embodiments to human subjects results in no more than 30%, 25%, 20%, 15%, 10% or 5% of the subjects experiencing Grade 3 fever, headache, fatigue, chills, myalgia, arthralgia, nausea and/or diarrhea.