On 17 June 2025, Regeneron filed a new BPCIA complaint against Amgen in the United States District Court for the Central District of California, asserting that Amgen’s Pavblu™/ABP 938 (aflibercept) infringes US 12,331,099, which claims an ophthalmic formulation of aflibercept. The US 099 patent was granted on the same date that Regeneron’s complaint was filed.
Regeneron is seeking an injunction preventing Amgen from infringing the US 099 patent, including by selling and distributing Pavblu™, damages in the form of lost profits, additional damages for wilful infringement and legal costs.
The new complaint follows the Court of Appeals for the Federal Circuit’s denial of Regeneron’s application for an injunction against Amgen’s Pavblu™ in October 2024 in respect of another of Regeneron’s US formulation patents (US Patent No. 11,084,865). In the earlier case, the Appeals Court determined that the relevant claims of the US 865 patent required an aflibercept formulation that included a separate buffer component, but Amgen’s formulation did not contain any such buffer.
Amgen’s Pavblu™, biosimilar to Regeneron’s Eylea® (aflibercept), was approved in August 2024 and launched in the US in October 2024 following the Court of Appeals’ decision.
Regeneron is seeking that the new complaint against Amgen be consolidated with its other pending aflibercept BPCIA litigation against each of Samsung Bioepis (2 actions; Opuviz™/SB15 approved May 2024), Formycon (Ahzantive®/FYB203 approved June 2024), Celltrion (2 actions, aBLA for CT-P42 submitted to FDA in June 2023) and Sandoz (Enzeevu™ approved August 2024). Preliminary injunctions were granted, and remain in place, preventing biosimilar aflibercept launches by Samsung Bioepis (14 June 2024, upheld on appeal on 29 January 2025), Formycon (21 June 2024, upheld on appeal on 29 January 2025) and Celltrion (June-July 2024, upheld on appeal on 5 March 2025).
Regeneron settled US BPCIA litigation regarding aflibercept with Biocon in April 2025, paving the way for a US launch of Biocon’s biosimilar, Yesafili™ (approved May 2024) in the second half of 2026, or earlier under certain undisclosed circumstances.
Samsung Bioepis, Formycon and Celltrion have been challenging the validity of Regeneron’s US 11,084,865 before the USPTO, having each filed a petition for IPR (inter partes review) in November 2024, December 2024 and January 2025, respectively. On 2 June 2025, the PTAB denied institution of Samsung Bioepis’ and Formycon’s petitions including because the ‘865 patent is already the subject of the pending BPCIA litigation. Celltrion’s petition remains pending.