Alza Corp. v. Amneal Pharmaceuticals of New York, LLC

Case Name: Alza Corp. v. Amneal Pharmaceuticals of New York, LLC, Civ. No. 16-cv-914-RGA, 2017 U.S. Dist. LEXIS 53551 (D. Del. Apr. 7, 2017) (Andrews, J.)

Drug Product and U.S. Patent: Concerta® (methylphenidate); U.S. Patent Nos. 8,163,798 (“the ’798 patent”) and 9,144,549 (“the ’549 patent”)

Nature of the Case and Issue(s) Presented: After Amneal filed its ANDA and a Major Complete Response Amendment with the FDA seeking to sell a generic version of Concerta, Plaintiffs filed this lawsuit claiming infringement of the patents-in-suit. Defendants filed a motion to dismiss requesting judgment on the pleadings under Fed. R. Civ. P. 12(c). The contested claims were of two basic types: (i) non-osmotic and osmotic dosage forms; and (ii) only osmotic dosage forms. As to the claims of category (i), Defendants based their argument on collateral estoppel grounds because the court previously invalidated similar claims for lack of enablement, a decision affirmed by the Federal Circuit. The court dismissed that portion of Defendants’ motion. As to the category (ii) claims, Defendants based their argument on non-infringement arguments. The court denied that portion of Defendants’ motion.

Why Alza Prevailed: The court dismissed the category (i) claims as moot because Alza elected not to assert claims covering non-osmotic dosage forms.

Concerning the category (ii) claims, and relying on the previous trial decision and Federal Circuit affirmance, Amneal argued that the claims requires both a “semipermeable membrane” and a “push layer.” These limitations, according to Amneal, resolved the infringement analysis because its ANDA product would not include a push layer. The court denied Amneal’s motion related to the category (ii) claims for three reasons.  First, court found that the Federal Circuit was not engaging in, or reviewing, claim construction because the district court never construed the term “osmotic dosage form.” Second, the court found that the Federal Circuit did not cite, or suggest it was relying on, the specification or any other intrinsic evidence for its description of osmotic dosage forms (because the Federal Circuit was not engaged in claim construction). Third, any description of osmotic dosage forms described in the prior Federal Circuit’s opinion was not necessary to the court’s holding. The enablement dispute focused exclusively on non-osmotic dosage forms, which did not reference a push layer for delineating what was enabled and what was not enabled. The court concluded, “I believe this case requires claim construction and probably expert testimony before a finding on infringement can be made.”