Last week, the United States Court of Appeals for the Federal Circuit issued an opinion in Neptune Generics, LLC v. Eli Lilly & Co., 2018-1257, 2018-1258 (April 26, 2019). Neptune Generics, Fresenius Kabi USA, and Mylan Laboratories (collectively, “Petitioners”) filed three inter partes review (IPR) petitions challenging the validity of Eli Lilly’s patent directed to a method of reducing the toxicity associated with the chemotherapeutic pemetrexed (ALIMTA®) by requiring co-administration with folic acid and a methylmalonic acid (“MMA”) lowering agent such as vitamin B12. The Petitioners alleged claims 1-22 of the Eli Lilly patent were obvious in view of a European patent application and two abstracts. The Patent Trial and Appeal Board (PTAB) concluded that, although pretreatment with folic acid was known in the prior art, the claimed combination of pretreating with folic acid and vitamin B12 was nonobvious. Petitioners appealed.
The Federal Circuit affirmed. The Court first examined the PTAB’s findings that the prior art failed to teach or suggest a link between vitamin B12 deficiency and pemetrexed toxicity, and concluded the PTAB’s findings were supported by substantial evidence. The Court further concluded that secondary considerations, namely skepticism by others, supported the PTAB’s decision. During the IPR, Eli Lilly had submitted correspondence from the FDA expressing the FDA’s doubts regarding vitamin pretreatment. The Petitioners asserted that to establish skepticism others must have thought the invention was “impossible”. The Court dismissed this argument stating “[w]hile evidence that third parties thought the invention was impossible might be entitled to more weight, that does not mean the Board erred in giving weight to the skepticism evidence here.”
The Court declined to address new arguments made by the Petitioners on appeal regarding patent eligibility under § 101. Asserting that eligibility is a “question of law” and that in the appeal there were no fact issues to be decided, Petitioners argued eligibility was properly raised and could be decided for the first time on appeal. The Court disagreed, explaining “Congress expressly limited the scope of inter partes review to a subset of grounds that can be raised under 35 U.S.C. §§ 102 & 103. . . . The ground of patent eligibility arises under § 101. Accordingly, we may not address it on appeal of an IPR.”