Impax Laboratories, Inc. (“Impax”) sued Aventis Pharmaceuticals Inc. (“Aventis”) in the United States District Court for the District of Delaware for a declaratory judgment that Impax did not infringe, induce infringement of, or contribute to the infringement of, U.S. Patent No. 5,527,814 (“the ’814 patent”) under 35 U.S.C. § 271(e)(2) by filing an Abbreviated New Drug Application (“ANDA”). In its suit, Impax alleged, inter alia, that the ’814 patent was invalid and unenforceable. Impax filed its ANDA under the provisions of the Patent Laws and Drug Price Competition and Patent Term Restoration Act of 1984, Pub. L. No. 98-417, 98 Stat. 1585 (1984), codified at 21 U.S.C. §§ 355, 360(c) (2000), 35 U.S.C. §§ 156, 271, and 282 (2000) (commonly referred to as the “Hatch-Waxman Act”). In its ANDA, Impax sought the approval of the United States Food and Drug Administration (“FDA”) to engage in the commercial manufacture and/or sale of riluzole tablets for the treatment of patients with amyotrophic lateral sclerosis (“ALS”).
Impax now appeals from the decision of the district court, following a bench trial, that it failed to prove (1) that the ’814 patent is unenforceable due to inequitable conduct and (2) that claims 1-5 of the ’814 patent are invalid as anticipated. See Impax Labs., Inc. v. Aventis Pharms., Inc., 333 F. Supp. 2d 265 (D. Del. 2004) (“Validity and Enforceability Order”). We see no error in the decision of the district court on the inequitable conduct issue. However, as far as the anticipation issue is concerned, we conclude that the court erred in its determination that one of the alleged two items of invalidating prior art did not enable a method of using riluzole to treat ALS and, therefore, could not serve as an anticipatory reference under 35 U.S.C. § 102(b). Accordingly, we affirm-in-part, vacate-in-part, and remand.
