LONDON (Reuters) - Britain's highest court upheld a patent on Wednesday on a gene sequence held by Human Genome Sciences related to its new lupus drug Benlysta, in a defeat for rival drugmaker Eli Lilly.

The UK Supreme Court ruling chimes with similar support for the patent by the European Patent Office (EPO) and overturns earlier British court decisions in favor of Eli Lilly. HGS had appealed against the earlier UK rulings.

"The supreme court unanimously allows the appeal ... and remits the case to the Court of Appeal to deal with the outstanding issues," judge David Hope said.

The case centers on a protein called neutrokine-alpha, which HGS identified and filed a patent for in 1996.

Following a challenge from Eli Lilly, lower courts in London decided the uses for neutrokine-alpha proposed in the patent were not plausible at the time it was filed, since research had not at that stage been conducted to establish its real-world value.

But in his ruling, Hope said this was not consistent with the EPO's position, and the disclosure of the existence and structure of neutrokine-alpha and its gene should have been sufficient.

After the original discovery of neutrokine-alpha, HGS worked with British drugmaker GlaxoSmithKline to develop Benlysta, or belimumab, for the treatment of lupus, a chronic life-threatening autoimmune disease.

Benlysta, the first new treatment for lupus for 50 years, was approved by European drug regulators in July following a green light from regulators in the United States in March.

Britain's BioIndustry Association, without favoring either side in the case, had made an intervention arguing against the idea that the hurdle for patentability should involve data from clinical trials to prove industrial applicability.

European biotechnology companies are concerned that onerous patent restrictions could disadvantage the sector.

Scientists and the biotech firms were alarmed last month when the European Court of Justice banned patenting any stem-cell process that involves destroying a human embryo, dealing a blow to an emerging field of medical research.

(Additional reporting by Kate Kelland; Editing by Hans-Juergen Peters and Greg Mahlich)