Federal Circuit Rebukes District Court for Patent Eligibility Decision Involving Extended-Release Formulation Patent
Posted in Intellectual Property
The U.S. Court of Appeals for the Federal Circuit[1] admonished the U.S. District Court for the District of Delaware on Wednesday for abuse of its discretion in finding the disputed claims invalid under 35 U.S.C. § 101, “a ground not invoked by [the defendant-appellee].”[2] The claims at issue are directed to a Food and Drug Administration-approved extended-release mirabegron tablet for the treatment of overactive bladder, marketed under the brand name Myrbetriq®.[3] The extended-release formulation addresses an undesirable food effect in which the bioavailability of the drug is affected by the presence or absence of food in the patient’s stomach.[4] This extended-release formulation is captured in U.S. Patent No. 10,842,780 (the ’780 patent). Exemplary claim 1 of the ’780 patent, directed to a pharmaceutical composition comprising mirabegron, is reproduced below:
A pharmaceutical composition, comprising 10 mg to 200 mg of [mirabegron], or a pharmaceutically acceptable salt thereof, in a sustained release hydrogel-forming formulation comprising a hydrogel-forming polymer having an average molecular weight of 100,000 to 8,000,000 and an additive having a water solubility of at least 0.1 g/mL at 20±5° C,
wherein the hydrogel-forming polymer is at least one compound selected from the group consisting of polyethylene oxide, hydroxypropyl methylcellulose, hydroxypropyl cellulose, carboxymethyl cellulose sodium, hydroxyethyl cellulose, and a carboxyvinyl polymer,
wherein the additive is at least one selected from the group consisting of polyethylene glycol, polyvinylpyrrolidone, D-mannitol, D-sorbitol, xylitol, lactose, sucrose, anhydrous maltose, D-fructose, dextran, glucose, polyoxyethylene hydrogenated castor oil, polyoxyethylene polyoxypropylene glycol, polyoxyethylene sorbitan higher fatty acid ester, sodium chloride, magnesium chloride, citric acid, tartaric acid, glycine, β-alanine, lysine hydrochloride, and meglumine, and
wherein a drug dissolution rate from the pharmaceutical composition is 39% or less after 1.5 hours, and at least 75% after 7 hours, as measured in accordance with United States Pharmacopoeia in 900 mL of a USP buffer having a pH of 6.8 at a paddle rotation speed of 200 rpm.
The decision from the district court aimed to resolve a lawsuit for patent infringement under 35 U.S.C. § 271(e)(2)(A) filed by the patent owner against various defendants[5] that centered on the defendants’ Abbreviated New Drug Application filings for approval to market generic versions of Myrbetriq.[6]
During the district court proceedings, the defendants raised invalidity contentions under 35 U.S.C. §§ 102, 103 and 112, and ultimately agreed to limit their defenses to those based on § 112 (for written description, enablement and indefiniteness).[7] In a surprising twist, the district court issued a final decision holding the asserted claims of the ’780 patent invalid under 35 U.S.C. § 101 as directed to an ineligible natural law.[8] As basis for its decision, the district court relied on the patent owner’s admission in the context of enablement that the inventive concept was the application of a “previously known formulation technology” to address the food effect.[9] The district court held that “[the patent owner] concedes that the ’780 patent is enabled because it claims invalid subject matter: a natural law applied via routine, conventional, and well-known methods.”[10]
The Federal Circuit reversed and remanded, and it chided the district court for “rendering its decision on a ground not raised by any party at any stage of the proceedings.”[11] The Federal Circuit acknowledged that the principle of party presentation “is supple, not ironclad,” but determined that “rendering a patent invalid on a basis not advanced by either party” was a step too far.[12]
In what appears to be an attempt to clarify the parameters of 35 U.S.C. § 101 disputes, the Federal Circuit cautioned that patent eligibility under § 101 is not “a threshold inquiry” akin to subject matter jurisdiction.[13] Instead, the presumption of validity “applies equally to all grounds of validity, including the eligibility of the claimed subject matter.”[14] The Federal Circuit dismissed the defendants’ invocation of public policy to justify the lower court’s decision, stating that any public interest in eliminating “invalid pharmaceutical patents that delay or deter low-cost generic alternatives” is “entirely irrelevant to the scope of a court’s authority to stray from the case as designed by the parties.”[15]
Additionally, the Federal Circuit denied the patent owner’s request to reassign the case to a different district court judge, finding that this “extraordinary remedy” of reassignment was not triggered by the court’s erroneous ruling.[16] Statements by the district court judge that the pharmaceutical industry had “perverted” the intent of Hatch-Waxman amendments, that brand and generic manufacturers had “colluded to protect weak or invalid patents and share in the startling profits,” and that the United States Patent and Trademark Office had “accommodated” the patenting of extended-release formulas for soon-to-expire active-ingredient patents were found to have “no relevance to the proceedings” in the case on appeal.[17] The Federal Circuit cautioned that “these proceedings are not an appropriate venue for those frustrations to be aired, let alone acted upon,”[18] but it expressed confidence that the district court would “take an objective, measured, and thorough look into the legal issues and evidence” on remand.[19]
[1] Judges Lourie, Prost and Reyna sat on the panel for the Federal Circuit.
[2] Astellas Pharma, Inc. v. Sandoz Inc., No. 2023-2032, 2024 WL 4219374, at *6 (Fed. Cir. Sept. 18, 2024).
[3] Id. at *1.
[4] Id.
[5] Sandoz Inc., Zydus Pharmaceuticals (USA) Inc., Zydus Lifesciences Ltd., dba Zydus Ca-Dila, Lupin Ltd., Lupin Pharmaceuticals Inc. and LEK Pharmaceuticals, D.D.
[6] Id. at *2.
[7] Id. at *3.
[8] Id.
[9] Id.
[10] Id.
[11] Id. at *4.
[12] Id.
[13] Id. at *5.
[14] Id.; emphasis in original.
[15] Id. at *6.
[16] Id.
[17] Id. at *7.
[18] Id.
[19] Id.