Mark your calendars – on December 9th, the Federal Circuit is slated to hear oral arguments as to whether two Amgen patents claiming a genus of antibodies meet the enablement requirement of 35 U.S.C. § 112. The court’s decision may have a considerable impact on antibody-based drug development and the scope of patent protection available for antibody innovations.
In one corner, there’s Amgen, backed by amici Bristol-Myers Squibb and Merck. In the other, we have Sanofi and Regeneron, supported by amici Eli Lilly and Pfizer. The tension has been building since 2014, when Amgen sued Sanofi and Regeneron for patent infringement of two patents (U.S. Patent Nos. 8,829,165 and 8,859,741) drawn to a class of drugs called PCSK9 inhibitors (and covering Amgen’s cholesterol-lowering drug Repatha). While the defendants conceded infringement, the validity of the patents was brought into question, and following a years-long legal rollercoaster, Amgen is now challenging U.S. District Judge Richard G. Andrews’s decision invalidating the patents for lack of enablement.
In his August 2019 ruling, Judge Andrews found that the Amgen patents claimed a “vast” class of antibodies, and that it would take “undue experimentation” to practice the full scope of the invention. Specifically, he explained that the claims were directed to a large genus of antibodies (Amgen says the genus comprises about 400 distinct antibodies; Sanofi argues the number is actually in the millions), but the written description only specified a small fraction of the species that fell within that genus. With a substantial gap between the number of potential and actual species, and a lack of significant guidance or direction in the patent to a person of ordinary skill in the art on how to predict whether an antibody will bind to specific PCSK9 residues, Judge Andrews concluded that the claims were not enabled under Section 112.
The question of antibody genus patentability raises unique challenges considering the industry of big pharma and the research and development efforts that goes into antibody-based drugs. On one hand, antibody development has been described as extremely costly, complex, unpredictable, and time-consuming, such that it makes more sense for a company to seek patent protection for the genus as soon as they have a discernible universe of antibody species. But on the other hand, as Sanofi argues, allowing such broad claims to antibodies not actually discovered may be just a strategic means to stifle competition.
Could the outcome of this case ultimately threaten antibody innovation? Or will companies just have to get more creative with patent claims? Stay tuned for a summary of the Federal Circuit oral arguments and predictions about the case moving forward in a follow-on December post.