FDA Approves Celltrion’s Biosimilars Stoboclo and Osenvelt

Image Credit: Adobe Stock Images/Keitma

The FDA has approved Celltrion’s Stoboclo (CT-P41, denosumab-bmwo) and Osenvelt (CT-P41, denosumab-bmwo), biosimilars referencing Amgen’s Prolia and Xgeva, respectively. Stoboclo is indicated for postmenopausal women with osteoporosis at high risk for fracture; to increase bone mass in men with osteoporosis at high risk for fracture; and for patients with glucocorticoid-induced osteoporosis. Osenvelt is indicated for the prevention of skeletal-related events in patients with multiple myeloma and bone metastases from solid tumors; skeletally mature adolescents with unresectable giant cell tumor of bone; and hypercalcemia of malignancy refractory to bisphosphonate therapy.¹

"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, Celltrion USA, in a press release. "Patients deserve therapeutic options that have the potential to make real impacts on their care and their lives. We are committed to continuous innovation to meet these goals leveraging our experience and successful track record with biosimilar and novel biologics."

The approvals were based on comprehensive Phase III clinical data demonstrating equivalent efficacy, pharmacodynamics, and pharmacokinetics, along with comparable safety and immunogenicity profiles to reference denosumab.

In women with postmenopausal osteoporosis who were treated with Stoboclo, the most common adverse events (AEs) included back pain, hypercholesterolemia, musculoskeletal pain, and cystitis. In men with osteoporosis, common AEs included back pain, arthralgia, and nasopharyngitis. In patients with glucocorticoid-induced osteoporosis, the most common AEs included back pain, hypertension, bronchitis, and headache. The most common AEs for patients with bone loss due to hormone ablation for cancer included arthralgia and back pain.

In patients treated with Osenvelt for bone metastasis from solid tumors, the most common AEs included asthenia, hypophosphatemia, and nausea. In patients with multiple myeloma, the most common AEs included diarrhea; nausea; anemia; back pain; thrombocytopenia; peripheral edema; hypocalcemia; upper respiratory tract infection; rash; and headache. The most common AEs for patients with hypercalcemia of malignancy included nausea; dyspnea; decreased appetite; headache; peripheral edema; vomiting; anemia; constipation; and diarrhea.¹

These regulatory actions marked the latest lower cost alternatives to Prolia and Xgeva to gain FDA approval. Last month, the FDA approved Samsung Bioepis’ Ospomyv (denosumab-dssb; SB16) and Xbryk (denosumab-dssb; SB16) as biosimilars to Prolia and Xgeva, respectively.²

According to the International Osteoporosis Foundation, osteoporosis affects one in three women as well as one in five men over 50 years of age. In the United States, it is estimated that 54 million people are at risk for osteoporosis. Additionally, 80% of the 10.2 million people in the United States that have it are women.³

"Denosumab is used to improve or protect bone health in patients with osteoporosis or those undergoing various cancer treatments and as a therapy for a lifetime for postmenopausal osteoporosis patients," said Jean-Yves Reginster, professor of medicine, protein research chair, biochemistry department, college of science, King Saud University, Riyadh, Kingdom of Saudi Arabia, director WHO Collaborating Center for Epidemiology of Musculoskeletal Health and Aging, Liège, Belgium, in the press release. "Biosimilars have expanded into new therapeutic areas such as immunology, oncology and ophthalmology as they continue to offer significant cost-saving potential while expanding patient access. Having a denosumab product with a clinically proven track record in quality and safety is a valuable addition for my patients."

According to Celltrion, both treatments are expected to launch in the United States in June, based on a settlement with Amgen.¹

References

1. Celltrion receives U.S. FDA approval for STOBOCLO® (denosumab-bmwo) and OSENVELT® (denosumab-bmwo) biosimilars referencing PROLIA® and XGEVA®. PR Newswire. March 3, 2025. Accessed March 4, 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

2. FDA Approves Samsung Bioepis Biosimilars Ospomyv and Xbryk. PharmExec. February 18, 2025. Accessed March 4, 2025. https://www.pharmexec.com/view/fda-approves-samsung-bioepis-biosimilars-ospomyv-xbryk

3. Epidemiology. IOF. Accessed March 4, 2025. https://www.osteoporosis.foundation/health-professionals/about-osteoporosis/epidemiology