The Food and Drug Administration (FDA) has approved Stoboclo® (denosumab-bmwo), a biosimilar to Prolia® (denosumab), and Osenvelt® (denosumab-bmwo), a biosimilar to Xgeva® (denosumab).
Stoboclo is approved to treat postmenopausal women with osteoporosis at high risk for fracture, to increase bone mass in men with osteoporosis at high risk for fracture, to treat glucocorticoid-induced osteoporosis in men and women at high risk for fracture, to increase bone mass in men at high risk for fracture receiving androgen deprivation therapy for nonmetastatic prostate cancer, and to increase bone mass in women at high risk for fracture receiving adjuvant aromatase inhibitor therapy for breast cancer.
Osenvelt is indicated to prevent skeletal-related events in patients with multiple myeloma and in patients with bone metastases from solid tumors, to treat adults and skeletally mature adolescents with giant cell tumor of bone that is unresectable or where surgical resection is likely to result in severe morbidity, and to treat hypercalcemia of malignancy refractory to biphosphonate therapy.
The biosimilar approval was based on a comprehensive clinical data package, which included a double-blind, randomized, active-controlled phase 3 trial (ClinicalTrials.gov Identifier: NCT04757376) that compared denosumab-bmwo to the reference product (Prolia) in postmenopausal women with osteoporosis.
The study included 2 treatment periods. During the first period, study participants (N=479) were randomly assigned 1:1 to receive denosumab-bmwo or the reference product. Patients who received the biosimilar in the first period continued to do so at week 52; those who received Prolia were randomly assigned to continue the treatment or switch to the biosimilar during the second part of the study, which continued through week 78. The primary endpoint was the percent change from baseline in lumbar spine bone mineral density at week 52.
Findings at week 52 showed equivalent efficacy for the primary endpoint between denosumab-bmwo and Prolia (least squares mean difference: full analysis set: -0.139 [95% CI, -0.826, 0.548]; per-protocol set: -0.280 [95% CI, -0.973, 0.414]). Comparable efficacy results were observed at week 78 after switching to the biosimilar from the reference product (secondary endpoint). Safety, pharmacokinetic, and immunogenicity data demonstrated the products were similar.
"The approval of Stoboclo and Osenvelt is another step forward in our efforts to deliver cost-effective and high-quality treatments that address critical unmet needs in osteoporosis-related fracture as well as cancer-related skeletal events," said Thomas Nusbickel, Chief Commercial Officer at Celltrion USA.
The products are expected to be available in June 2025.
This article originally appeared on MPR
References:
Celltrion receives US FDA approval for Stoboclo® (denosumab-bmwo) and Osenvelt® (denosumab-bmwo) biosimilars referencing Prolia® and Xgeva®. News release. Celltrion. March 3, 2025. https://www.prnewswire.com/news-releases/celltrion-receives-us-fda-approval-for-stoboclo-denosumab-bmwo-and-osenvelt-denosumab-bmwo-biosimilars-referencing-prolia-and-xgeva-302390957.html. Reginster JY, Czerwinski E, Wilk K, et al. Efficacy and safety of candidate biosimilar CT-P41 versus reference denosumab: a double-blind, randomized, active-controlled, Phase 3 trial in postmenopausal women with osteoporosis. Osteoporosis International. Published online July 23, 2024. doi:10.1007/s00198-024-07161-x Stoboclo. Package insert. Celltrion; 2025. Accessed March 4, 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/761404s000lbl.pdf. Osenvelt. Package insert. Celltrion; 2025. Accessed March 4, 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/761404s000lbl.pdf.