The US Food and Drug Administration approved two denosumab biosimilars—Bildyos (denosumab-nxxp) and Bilprevda (denosumab-nxxp)—for all approved indications of the reference products Prolia and Xgeva. The approvals expand therapeutic options for conditions such as osteoporosis, bone metastases, giant cell tumor of bone, and hypercalcemia of malignancy.

Bildyos is indicated for postmenopausal women and men with osteoporosis at high risk for fracture, glucocorticoid-induced osteoporosis, and bone loss associated with androgen deprivation therapy in prostate cancer or aromatase inhibitor therapy in breast cancer. Use in patients with advanced kidney disease is associated with increased risk of severe hypocalcemia, particularly in those with chronic kidney disease–mineral bone disorder and should be managed by clinical specialists in mineral metabolism.

Bilprevda is indicated for prevention of skeletal-related events in patients with multiple myeloma or bone metastases from solid tumors, as well as treatment of unresectable giant cell tumor of bone and hypercalcemia of malignancy refractory to bisphosphonates. Safety considerations include risk of severe hypocalcemia, hypersensitivity reactions, and osteonecrosis of the jaw. Dental evaluation and calcium and vitamin D supplementation are recommended prior to and during therapy. Both biosimilars carry risks of atypical femoral fractures and vertebral fractures following discontinuation, requiring careful patient monitoring.

Regulatory approval was supported by comparative analytical, pharmacokinetic, and clinical data showing no clinically meaningful differences from the reference biologics in terms of safety, purity, or potency. Henlius and Organon entered into a global licensing agreement in 2022, granting Organon exclusive commercialization rights outside China.

Source: Organon