Health your username February 12, 2021 In a suit brought by Amgen Inc., Amgen Manufacturing, Ltd., and Amgen USA, Inc. (collectively, Amgen) against Sanofi, Aventisub LLC, Regeneron Pharmaceuticals Inc., Sanofi-Aventis U.S. LLC (collectively, Sanofi) more than six years ago, the Federal Circuit has affirmed the district courtâs determination that certain Amgen patent claims were invalid for lack of enablement. The asserted claims of Amgenâs two patents describe antibodies that help the body regulate low-density lipoprotein cholesterol (LDL). According to Thursdayâs opinion, this was the second time the patents have been before the Federal Circuit. The present dispute concerned whether Amgenâs asserted claims were invalid for lack of enablement. In order to pass the federal enablement requirement, the court explained, the question is whether one reasonably skilled in the art could make or use the invention from the disclosures in the patent coupled with information known in the art without undue experimentation.