130 F.4th 1372
Fed. Cir.2025Background
- Regeneron Pharmaceuticals, Inc. owns the ‘865 patent, directed to formulations of aflibercept (EYLEA®), an ophthalmic drug used to treat certain vision disorders by inhibiting VEGF.
- Amgen sought FDA approval to market ABP 938 (Pavblu), a proposed biosimilar to EYLEA, but formulated without a separate buffer because the active protein itself provided sufficient buffering capacity.
- Regeneron alleged Amgen’s aBLA for ABP 938 infringed several claims in the ‘865 patent, and sought a preliminary injunction in the U.S. District Court for the Northern District of West Virginia.
- The district court denied the injunction, holding that Regeneron did not show a likelihood of success on infringement because, under claim construction rules, the asserted claims required distinct buffer and protein components.
- Regeneron appealed, challenging claim construction and, specifically, the application of the Federal Circuit’s Becton precedent requiring separately listed claim elements to be distinct unless rebutted by intrinsic or extrinsic evidence.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Does Becton presumption apply to the claim's listing of 'VEGF antagonist' and 'buffer' as separate elements? | Becton inapplicable because ordinary meaning of 'buffer' covers proteins like aflibercept; prior precedent interpreted 'buffer' broadly. | Becton applies; claim language and structure require 'VEGF antagonist' and 'buffer' as distinct components. | Becton applies; claim language lists four distinct components, supporting presumption of separateness. |
| Can the intrinsic evidence rebut the presumption that 'VEGF antagonist' and 'buffer' are distinct? | Intrinsic record permits overlap; specification and claims do not preclude aflibercept as a buffer. | Intrinsic evidence uniformly treats the two as separate; every example and embodiment supports distinction. | Presumption not rebutted; intrinsic evidence reinforces distinction between components. |
| Does the extrinsic evidence compel a contrary result? | Extrinsic references (including scientific articles and expert testimony) show proteins can be buffers, supporting overlap. | Extrinsic evidence does not outweigh intrinsic evidence; references show buffer-free proteins were not conventional. | Court gives priority to intrinsic evidence; extrinsic evidence does not show proteins like aflibercept functioned as buffer in art. |
| Did the district court err in denying preliminary injunction on noninfringement grounds? | Court misapplied claim construction and ignored evidence, wrongly denying injunction. | Properly applied law and evidence, establishing substantial question of noninfringement. | No error; Regeneron failed to show likelihood of success because Amgen’s product lacked required separate buffer. |
Key Cases Cited
- Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (foundational case for claim construction principles; claim terms construed in light of specification and prosecution history)
- Becton, Dickinson & Co. v. Tyco Healthcare Group, 616 F.3d 1249 (Fed. Cir. 2010) (where claim lists elements separately, presumption that those elements are distinct components)
- Kyocera Senco Indus. Tools Inc. v. Int’l Trade Comm’n, 22 F.4th 1369 (Fed. Cir. 2022) (reaffirms Becton presumption that separately listed elements are distinct absent contrary intrinsic evidence)
- Schindler Elevator Corp. v. Otis Elevator Co., 593 F.3d 1275 (Fed. Cir. 2010) (claim terms indicating distinct entities typically indicate separate components)
- Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996) (claims construed consistent with the specification regarded as a whole)
- Genentech, Inc. v. Novo Nordisk A/S, 108 F.3d 1361 (Fed. Cir. 1997) (preliminary injunction requires showing of likelihood of success; substantial question precludes injunction)