On 5 March 2025, the US Court of Appeals for the Federal Circuit refused to overturn a preliminary injunction preventing Celltrion from launching its biosimilar to Regeneron’s Eylea® (aflibercept) in the US without a licence from Regeneron.
In doing so, the Appeals Court affirmed the 28 June 2024 decision of the US District Court for the Northern District of West Virginia, finding that Celltrion infringed, and had failed to raise a substantial question of invalidity of, Regeneron’s US Patent No. 11,084,865 regarding ophthalmic formulations of aflibercept.
Celltrion’s CT-P42 (aflibercept) has not yet been approved in the US, although Celltrion filed an NDA with the FDA in June 2023. CT-P42 (marketed as Eydenzelt®) was approved in Korea in May 2024 and received a positive CHMP opinion from the European Medicines Agency in December 2024.
The decision against Celltrion follows similar Appeals Court decisions in January 2025 upholding preliminary injunctions against Samsung Bioepis’ and Formycon’s aflibercept biosimilars, Opuviz™/SB15 (US approval received May 2024) and Ahzantive®/FYB203 (FDA-approved in June 2024), respectively.
The US District Court for the Northern District of West Virginia has also granted a permanent injunction against Biocon (11 June 2024), based on findings of infringement of the same patent (US ‘865). Biocon filed a Notice of Appeal from the permanent injunction order on 21 June 2024. That appeal remains pending.
In October 2024, the Court of Appeals denied Regeneron’s application for an injunction against Amgen. As a result, Amgen launched its aflibercept biosimilar, Pavblu®, in the US later the same month.
Samsung Bioepis, Formycon and Celltrion are challenging Regeneron’s ‘865 patent before the USPTO, each having filed a petition for inter partes review (in November 2024, December 2024 and January 2025, respectively).