Federal Circuit Affirms Validity of Endo Pharmaceuticals Patent for Morphinan Pain Relief Compounds
The Federal Circuit recently affirmed a district court ruling finding patent infringement after holding that Actavis LLC, Actavis South Atlantic LLC, and Teva Pharmaceuticals USA, Inc. (collectively, “Actavis”) failed to prove by clear and convincing evidence that the claims asserted by Endo Pharmaceuticals and Mallinckrodt LLC (collectively, “Endo”) were invalid. See Endo Pharms., Inc. v. Actavis LLC, No. 2018-1054, 2019 U.S. App. LEXIS 13348 (Fed. Cir. May 3, 2019) (Before Wallach, Clevenger, and Stoll J.) (Opinion for the Court, Wallach, J.) (Dissenting opinion, Stoll, J.). However, the decision was not a unanimous one, with Judge Stoll authoring a dissent that would have reversed the district court. The patent at issue, U.S. Patent No 8,871,779 (the “‘779 patent”), is directed generally to compounds known as “morphinan alkaloids,” which are used for pain relief. More specifically, the ‘779 patent concerned processes for making “highly pure” morphinan products in the form of hydrochloride salts. Actavis claimed that the ‘779 patent was invalid, citing three key references as prior art. The first reference was a scientific article from 1957 by Ulrich Weiss (the “Weiss reference”) discussing a method for producing oxymorphone, a compound within the scope of the asserted claims. The second reference was U.S. Patent Application No. 2005/0222188 (the “Chapman reference”), which disclosed a purification process related to the asserted claims. Finally, the third reference was another article from 1967 by Henry Rapoport et al. (the “Rapoport reference”), which disclosed another purification process for oxycodone. The district court found that none of these references rendered the asserted claims obvious, and Actavis appealed.