On 3 March 2025, Celltrion announced that it has received US FDA approval for Stoboclo® and Osenvelt® (CT-P41), biosimilars to Amgen’s Prolia® and Xgeva® (denosumab), respectively, for the same indications as the reference medicines. The approval follows European approval of Celltrion’s denosumab biosimilars in February 2025.
Stoboclo® and Osenvelt® are the third denosumab biosimilars to be approved in the US, trailing Samsung Bioepis’ Ospomyv™ and Xbryk™ (February 2025), and Sandoz’s Wyost® and Jubbonti® (March 2024).
Celltrion filed its aBLA for CT-P41 in the US in December 2023. However, in May 2024, Celltrion was sued by Amgen in the District Court of New Jersey for alleged infringement of 29 patents regarding denosumab. That litigation was settled in January 2025, allowing Celltrion to launch its denosumab biosimilars in the US from 1 June 2025.