Big Molecule Watch
October 27, 2020

Federal Circuit Affirms PTAB Finding that Dupixent® Immunex Patent is Obvious

As previously reported, in February 2019, the Patent Trial and Appeal Board issued final written decisions in two IPR proceedings initiated by Sanofi challenging the U.S. Patent No. 8,679,487 (the ’487 patent) owned by Immunex.  In IPR2017-01884, the Board held that the challenged claims of the ‘487 patent were unpatentable in view of the grounds raised by Sanofi, but it came to the opposite conclusion in IPR2017-01879.  Both parties appealed, and the appeals were consolidated.  On October 13, 2020, the Federal Circuit affirmed the invalidity decision in IPR2017-01884.  See Immunex Corp. v. Sanofi-Aventis U.S. LLC, No. 2019-1749, 2020 WL 6038926, at *4 (Fed. Cir. Oct. 13, 2020).  Because that invalidity decision left no claims in the ‘487 patent at issue, the Federal Circuit dismissed Sanofi’s appeal from the Board’s decision in IPR 2017-01879.

The Board’s decision in IPR2017-01884 was predicated on its construction that the term “human antibody” included both fully human and partially human antibodies.  On appeal, Immunex argued that the Board erred in its construction.  First, Immunex argued that the Federal Circuit, in considering the meaning of “human antibody,” should apply the Phillips district-court claim construction standard, as opposed to the broadest reasonable interpretation (BRI) standard.  The Federal Circuit explained that presently, the Board applies the Phillips standard in all new IPRs.  When Sanofi filed its IPRs, however, the Board only applied the Phillips standard to expired patents and applied the BRI standard to unexpired patents.  Because Immunex’s patent was not expired at the time of Sanofi’s IPR, the Board applied the BRI standard in construing “human antibody.”  After appellate briefing was complete in the appeal from IPR1027-01884, Sanofi filed a terminal disclaimer of its patent, which the Patent Office accepted, causing the patent to expire on May 26, 2020, two months before oral argument.  Immunex then asked the Federal Circuit to apply the Phillips standard, rather than the BRI standard as applied by the Board, in construing the term “human antibody” on appeal.  The Federal Circuit declined, explaining that, among other things, it would “review the decision from which an appeal is taken on the record before the [PTO].”  It also noted that Immunex never requested briefing on the “implications of a possible pivot to Phillips.

Second, applying the BRI standard, the Federal Circuit concluded that the Board’s construction was correct.  The Federal Circuit held that the intrinsic record—i.e., the claims, specification, and prosecution—all supported the Board’s construction, and it declined to give weight to the extrinsic evidence cited by Immunex, because the “intrinsic evidence squarely conflict[ed]” with it.  The Federal Circuit further addressed Immunex’s argument that the Board’s construction of “human antibody” departed from a district court’s earlier construction limiting “human antibody” to fully human antibody, and that the Board should have explained in more detail why it came to a different outcome.  Dismissing Immunex’s argument, the Federal Circuit explained that the Board’s construction was “sufficiently detailed to permit meaningful appellate review.”



The post Federal Circuit Affirms PTAB Finding that Dupixent® Immunex Patent is Obvious appeared first on Big Molecule Watch.