IP Law Daily, PATENT—Fed. Cir.: Board properly found that claims in Pfizer patent related to pneumococcal vaccines are unpatentable as obvious, (Mar 5, 2024)

By Robert Margolis, J.D.

Court rejects Pfizer arguments that Board improperly applied “result-effective variable doctrine,” and that unpredictability of pneumococcal glycoconjugate vaccines precludes obviousness finding.

Substantial evidence supported the Patent Trial and Appeal Board’s conclusion that claims in a Pfizer Inc. patent directed to immunogenic compositions for use in pneumococcal vaccines are unpatentable as obvious, the Federal Circuit in Washington, D.C., has held. In upholding the obviousness finding, the court rejected Pfizer’s contentions that the Board erred in applying the “result-effective variable doctrine,” and that the “unpredictability” of pneumococcal glycoconjugate vaccines precludes an obviousness finding. The court also affirmed the Board’s denial of Pfizer motions to amend to add four proposed claims, while vacating the Board’s denial as to two other proposed claims, noting that Board did not sufficiently state its reasons for the denial as required by the Administrative Procedure Act. The Board was addressing Pfizer’s appeal of five separate inter partes review (“IPR”) proceedings brought by Merck Sharp & Dohme Corp. and Sanofi Pasteur Inc. and SK Chemicals Co. (Pfizer Inc. v. Sanofi Pasteur Inc., March 5, 2024, Lourie, A.).

Vaccine patent. Pfizer owns U.S. Patent No. 9,492,559 (the “’559 patent”), directed to immunogenic compositions comprising Streptococcus pneumoniae capsular saccharide antigens (known as glycoconjugates), to be used in pneumococcal vaccines. The ’559 patent’s only independent claim (“Claim 1”) included a range of molecular weights for the glycoconjugate, and identified one particular S. pneumoniae serotype. All other claims in the ’559 patent are dependent on Claim 1, reciting that the composition further includes various additional glycoconjugates. The appeal specifically discussed two of those dependent claims (Claims 3 and 4).

Obviousness contention. Sanofi and Merck separately challenged all claims of the ’559 patent in five IPR reviews, asserting the claims would have been obvious over prior art references in Patent Application Publications. After the Board rendered its decisions in favor of Sanofi and Merck, and also denied contingent motions by Pfizer to amend to substitute claims, finding the proposed claims also to be unpatentable, Pfizer appealed.

“Result-effective variable doctrine.” Pfizer contended that the Board erred when it found Claim 1 to be obvious because the Board should not have applied the “result-effective variable doctrine.” Pfizer argued the doctrine does not apply because the prior art references do not disclose any molecular weight for the claimed glycoconjugate, and the doctrine is appropriate only when there is overlap between the range in prior art and the claimed range in the challenged patent. The court found Pfizer’s argument unavailing.

As the court reasoned, whether a claimed parameter is a result-effective variable is part of a larger “routine optimization analysis,” based on the legal principle that “where general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” In re Aller, 220 F.2d 454, 456 (CCPA 1955). When numerical ranges are at issue, such as the molecular weight range set forth in Claim 1, and when there is an overlap between the claimed range and a prior art range, that creates a presumption of obviousness that can be rebutted by evidence showing the range parameters were not recognized as result-effective. Pfizer took that to argue obviousness can only be found where the ranges in prior art and the claim-at-issue overlap, and since there were no ranges as to the claimed glycoconjugate in the prior art, the doctrine simply does not apply. But as the court pointed out, routine optimization analysis considers “whether a person of ordinary skill in the art would have been motivated, with a reasonable expectation of success, to bridge any gaps in the prior art to arrive at the claimed invention.” If the gap includes a parameter that the prior art does not necessarily disclose, it is proper to consider whether that parameter would have been recognized as result-effective. If so, then the parameter will be found to be obvious.

The court found that substantial evidence supported the Board’s conclusion that the molecular weight cited in Claim 1 would have been obvious over the prior art references. While the prior art did not disclose a weight range for the particular glycoconjugate in the ’559 patent, one prior art reference disclosed another glycoconjugate of the same serotype, and a weight range overlapping the range in Claim 1. The prior art references also disclosed methods to prepare glycoconjugates and size polysaccharides to improve the filterability of the conjugated product.

The court rejected Pfizer’s argument that finding the correct glycogonjugate molecular weight requires “case-by-case experimentation,” such that any effective results would have to be considered unexpected. While that might be true in some situations, here the methods for creating the glycoconjugates were generally recognized as routine.

Unpredictability. The court similarly rejected Pfizer’s argument as to the dependent Claims 3 and 4, that because the prior art did not disclose that any of the claimed glycoconjugates were actually made or tested, the Board erred in its finding that there would have been a reasonable expectation of success in formulating the claimed serotypes that were “immunogenic conjugates.” Pfizer contended that the unpredictability of the art is high, thus precluding the possibility of a reasonable expectation of success. The court disagreed. The court has previously rejected the attempt to equate unpredictability with patentability, since the expectation of success need only be reasonable, not absolute. Substantial evidence supported the Board’s finding that the chance of success in arriving at the immunogenic compositions of Claims 3 and 4 was reasonable.

Motions to amend. The Board had denied Pfizer’s contingent motion to amend, filed in three of the five IPRs, to add six new claims. The Board found those proposed claims to be obvious as well. The court affirmed the decisions as to four of those claims, holding the Board correctly found that success could be reasonably expected on those claims, and that the Board sufficiently explained its reasoning. However, as to the other two claims, the Board’s decisions were silent as to why they would have been obvious over the references. Because administrative agencies must provide “reasoned basis” for their actions so as to provide meaningful basis for judicial review, and the decisions regarding two of the proposed claims did not meet that standard, the court vacated and remanded so the Board could further consider Pfizer’s motions as to those claims.

Director review procedure. The court also found unavailing Pfizer’s argument that the PTO’s Director Review procedure violates the Administrative Procedure Act. Pfizer contended the “PTO has unpredictably changed the [Director Review] Q&A webpages” without providing sufficient notice to the public of the Director Review process post-Anthrex. But as the court previously held, even if the webpage guidance is subject to the notice-and-comment procedure applicable to rulemaking, absent a showing of prejudice, any such error would be harmless. As Pfizer did not show any prejudice, indeed it did not show any part of the procedure of which it was unaware, any APA violation would be harmless error and would not be grounds for reversing any of the Board’s decisions.

The Case is Nos. 19-1871, 19-1873, 19-1875, 19-1876, 19-2224.

Attorneys: John P. Scheibeler (White & Case LLP) for Pfizer Inc. Siegmund Y. Gutman (Proskauer Rose LLP) for Sanofi Pasteur Inc., SK Chemicals Co., Ltd., and Merck Sharp & Dohme Corp.

Companies: Pfizer Inc.; Sanofi Pasteur Inc.; SK Chemicals Co., Ltd.; Merck Sharp & Dohme Corp.

MainStory: TopStory Patent FedCirNews USPTO GCNNews