Federal Circuit Upholds PTAB Finding of Obviousness in Pfizer vs. Sanofi

Attorney: Cristina Lai
March 18, 2024

In Pfizer Inc. vs. Sanofi Pasteur Inc., the Federal Circuit upheld the Patent Trial and Appeal Board (PTAB) decision to invalidate portions of Pfizer’s pneumococcal vaccine patent on the grounds of obviousness. My colleague’s post discusses the Federal Circuit’s decision to vacate and remand to the PTAB to further consider Pfizer’s motions to amend with regards to proposed claims 48 and 49, holding that the PTAB has not actually addressed the additional limitations for these claims. This post will focus on the patentability of Claims 1-45, and specifically how the Federal Circuit affirmed the PTAB’s application of the result-effective variable doctrine and reasonable expectation of success in order to arrive at a finding of obviousness of Claims 1-45 of U.S. Patent No. 9,492,599 (“the ‘559 patent”).<... Read more