On 24 January 2025, Amgen announced that it has settled its patent infringement litigation against Celltrion in the US District Court for the State of New Jersey, relating to Celltrion’s biosimilar denosumab.
Amgen had commenced proceedings against Celltrion in May 2024, alleging infringement of 29 patents relating to denosumab. The allegations followed Celltrion’s abbreviated Biologics Licence Application (aBLA) submitted in December 2023 for CT-P41, its biosimilar to Amgen’s Xgeva® and Prolia® (denosumab).
Pursuant to the settlement agreement, the parties consented to the Court making an order that the asserted claims of the 29 patents in suit are valid, enforceable and infringed by the exploitation of Celltrion’s biosimilar products in the US. The Court further granted an injunction, by consent, preventing it from making or selling its biosimilar denosumab in the US, except as permitted by the confidential settlement agreement.
The injunction expires on 1 June 2025, permitting Celltrion to launch its denosumab products in the US from that date.
The proceeding against Celltrion was one of five that Amgen had commenced in the US in relation to denosumab biosimilars. A dispute with Sandoz, commenced in May 2023, was resolved in April 2024, enabling Sandoz to launch its denosumab biosimilars, Jubbonti® and Wyost®, from 31 May 2025 (or earlier in certain undisclosed circumstances). The remaining court proceedings, against Fresenius Kabi (FKS518/commenced October 2024), Samsung Bioepis (SB16/commenced August 2024) and Accord/Intas (INTP23/commenced November 2024), remain pending.
Sandoz’s Wyost® and Jubbonti® were the first denosumab biosimilars approved in the US in March 2024. No other denosumab biosimilars have been approved in the US to date, although Gedeon Richter/Hikma (December 2024), Organon/Shanghai Henlius (October 2024), Teva (October 2024), and Fresenius Kabi (May 2024) have each had Biologics Licence Applications accepted for review by the FDA.
Celltrion’s Osenvelt®/CT-P41, biosimilar to Amgen’s Xgeva®, and Stoboclo®/CT-P41, biosimilar to Amgen’s Prolia®, received positive opinions from the EMA’s CHMP in December 2024.