Final Written Decision Relies on Unexpected Results To Uphold Pozen’s Ulcer Reducing Vimovo® Claims Over Kyle Bass’s IPR Challenge

Written by Kerry S. Taylor, Ph.D. and Nathanael Luman, Ph.D.

The PTAB issued a Final Written Decision upholding Pozen’s ulcer reducing Vimovo® claims based on unexpected results in Coalition For Affordable Drugs VII LLC v. Pozen Inc., IPR2015-01718, Paper 40 (P.T.A.B., Feb. 21, 2017).

Kyle Bass’s patent challenging entity, Coalition for Affordable Drugs (“Coalition”), filed an inter partes review (“IPR”) petition challenging all claims of an Orange Book-listed Vimovo® patent owned by Pozen Inc. (“Pozen”).  The patent claims are directed to a method of reducing ulcers in patients taking aspirin, where the method includes administering an ulcer medication, esomeprazole, and a nonsteroidal anti-inflammatory drug, naproxen.  Coalition asserted the claims were obvious based on two separate grounds, and the Board instituted the IPR proceeding as to both grounds.

Coalition argued in its petition that the prior art teaches the benefit of administering the claimed drug combination to patients taking aspirin.  In its patent owner response, Pozen argued that Coalition’s primary reference had only a single teaching of patients taking aspirin, and that teaching did not mention administering the drug combination recited in the claims.  Pozen also argued that the claimed method of administering the drug combination lead to unexpected results. 

In the Final Written Decision, the Board agreed with Coalition and found that the petition had established that the ordinary artisan would have been guided by the primary reference to administer the claimed drug combination to patients taking aspirin.  However, the Board continued its analysis by considering Pozen’s evidence of unexpected results.  All of Pozen’s claims included a clause reciting that administering the claimed drug combination is more effective at reducing ulcers in patients taking aspirin than in patients not taking aspirin.  Pozen presented an expert declaration discussing data that patients taking naproxen had increased ulcers when taking aspirin in combination with naproxen, but patients taking naproxen plus esomeprazole (the claimed combination) had decreased ulcers when taking aspirin in combination with naproxen and esomeprazole.  Coalition argued that secondary references asserted in the petition taught this result.  The Board, however, held that Coalition did not identify the basis for this assertion, and, thus, Coalition’s argument was entitled to little weight.  The Board went on to find that Pozen’s asserted unexpected results represented a difference in kind, and not simply in degree.  As such, the Board held that Pozen’s “surprising result” established the non-obviousness of the claims over Coalition’s asserted references.

This case provides a relatively rare example of a patent owner successfully overcoming a prima facie case of obviousness by presenting evidence of unexpected results.