Sofosbuvir - USA

On Oct 30, 2019, Federal Circuit affirmed Delaware Court's decision which found Idenix’s patent invalid for lack of enablement and additionally CAFC also found that said patent is invalid for lack of written description requirements.

Previously plaintiffs, Idenix Pharmaceuticals LLC and Universita Degli Studi di Cagliari (together, "Idenix") sued Defendant Gilead Sciences, Inc. ("Gilead"). Prior to trial, Gilead stipulated that, under the Court's claim construction, its accused products, Harvoni and Sovaldi, infringe the asserted claims of ldenix's patent, U.S. Patent No. 7,608,597 ("'597 patent"). After a two week-trial in December 2016, a jury found that Gilead failed to prove that the asserted claims are invalid and awarded Idenix $2.54 billion in damages. Gilead then requested judgment as a matter of law ("JMOL"). In its JMOL motion, Gilead argued that Idenix's asserted patent claims are invalid for failure to meet 35 U.S.C. § 112's written description and enablement requirements. District court granted motion with respect to lack of enablement & found patent invalid. However, court denied motion with respect to written description. Please see the previous blog "reported here".

During appeal, Federal Circuit affirmed district court regarding lack of enablement. Specifically, court held that patent fails to disclose "2-methyl up & 2-fluro down" position on nucleoside as claimed. Therefore, claimed method of treatment using generic formula encompasses thousands of compounds & POSA would not be able to come up with specific compound without undue experimentations. Court considered "Wands factor" and held that it favours lack of enablement.

With respect to written description, Federal Circuit reversed district court which denied the motion. Federal Circuit said that the question is whether the inventor had possession of "2-methyl up" along with "2-fluro down" nucleoside compounds having antiviral activity as per entire scope of claim. Idenix argued that generic compounds can be satisfied by representative number of species in the specification. But court said that there should be blaze marks instead of pointers in the specification in order to satisfy written description requirement. Here, specification fails to provide blaze marks for "2-methyl up" compounds which are used to treat HCV. Specification does not identify which compounds are useful in treating HCV and which are not. Moreover, the absence of "2-fluoro down" is indeed conspicuous. Examples disclose this "2-fluoro" group at "up" position and not at "down" position. Idenix argued that though fluorine is not directly mentioned at "down" position but POSA would have find it obvious to include it there in view of the other halogens. But Federal Circuit said that a description that merely renders the invention obvious does not satisfy the written description requirement.

Thus, the patent is invalid for lack of enablement as well as for lack of written description requirement.