Idenix v. Gilead: Split CAFC Panel at Least Agrees – Valid or Not, Either Way it’s Idenix Loss – Claims Too Broad

Idenix Pharmaceuticals LLC v. Gilead Sciences Inc. (Fed. Cir. 2019); 941 F.3d 1149 (2018 WL 922125) CAFC Panel: Chief Judge Prost and Circuit Judges Newman and Wallach
Opinion by Chief Judge Prost; dissenting opinion by Circuit Judge Newman

Idenix claims invalid / not enabled

Chemical structure of sofobuvir
sofosbuvir

Background: Idenix’s sued Gilead claiming Gilead’s sofosbuvir (Solvadi®) HCV treatment would infringe U.S. Patent No. 7,608,597, directed to methods for treating hepatitis C virus (HCV). Gilead argued that they should not be liable for infringement because the ‘597 patent was not valid since the patent’s specification did not enable the claims. At first, a jury at the district court level said that the claims of the ‘597 patent were enabled and therefore valid. However, the district court judge disagreed and granted Gilead’s Motion for a Judgment as of Matter of Law (JMOL), overruling the jury. When Idenix appealed, the United States Court of Appeals for the Federal Circuit (CAFC) affirmed the district court’s decision, agreeing that the ‘597 patent was invalid and therefore Gilead was not liable for infringement. In the end, the U.S. Supreme Court refused to hear the case [cert. denied, 141 S. Ct. 1234 (2021)].

CAFC Panel Split: In the Opinion, Chief Judge Prost and Circuit Judges Wallach agreed that Idenix’s ‘597 patent claims were not enabled. Circuit Judge Newman dissented, arguing that the ‘597 patent, although having overly broad claims, was still valid. However, while still valid, the claims should be interpreted narrowly, allowing Gilead to avoid liability anyway.

Common Ground: Let’s focus upon where all three judges agreed – Idenix should loose. While much attention has been given to how the panel was split as to whether the ‘597 patent was valid or not, we should remind ourselves that all three at least agreed that Gilead should not be liable for infringement. All three judges appeared to agree that Idenix’s claims were too broad. They diverged on how to get Gilead off the hook.

Loss either way:

(1) Majority – Rule that the claims are invalid by lack of enablement.

(2) Dissent – Rule that the claims are valid but not enforceable.

Forward to Amgen vs. Sanofi:

Circuit Judge Lourie’s Opinion in AMGEN INC. v. SANOFI, No. 20-1074 (Fed. Cir. 2021) referenced Idenix in concluding that Amgen’s claims were invalid as non-enabled.

The Supreme Court of the United States is set to hear arguments in Amgen on March 27, 2023. Stay tuned!