FDA Approves First Biosimilars for Prolia and Xgeva

The FDA has approved the first biosimilars for denosumab that reference Amgen’s osteroporisis drug Prolia and the bone cancer drug Xgeva. Developed by Sandoz, both biosimilars are interchangeable with the reference products for all indications.

Wyost (denosumab-bbdz) is approved to prevent skeletal-related events in patients with multiple myeloma and in patients with bone metastases from solid tumors. It is also approved to treat adults and skeletally mature adolescents with giant cell tumor of bone and hypercalcemia of malignancy refractory to bisphosphonate therapy.

Bone is the third most frequent site for metastatic tumors. Nearly all types of cancer can spread to the bone and cause pain and fractures, though cancers that often metastasize in bones include breast and prostate.

Jubbonti (denosumab-bbdz) is approved to treat several conditions, including men and postmenopausal women with osteoporosis. It is also approved to treat glucocorticoid-induced osteoporosis in men and women, to increase bone mass in men receiving androgen deprivation therapy for nonmetastatic prostate cancer, and for women receiving adjuvant aromatase inhibitor therapy for breast cancer.

Osteoporosis is a bone disease that develops when bone mineral density and bone mass decrease or when bone strength and structure change. More than 10 million U.S. adults aged 50 and over live with osteoporosis, a major cause of fractures in postmenopausal women and in older men.

Wyost and Jubbonti have the same dosage form, route of administration, dosing regimen as the reference medicines. Sandoz, however, would not comment on when Wyost and Jubbonti will be available. Patent litigation around these products is ongoing.

The FDA approval is based on data from analytical and clinical data package, including data from the phase 1/3 ROSALIA study. Results confirmed that the proposed biosimilar denosumab matches the reference medicine in terms of pharmacokinetics, pharmacodynamics, efficacy, safety and immunogenicity in women with postmenopausal osteoporosis; and contributes to demonstration of similarity.

The most common side effects of Wyost, like Xgeva, are tiredness/weakness, low phosphate levels in your blood, diarrhea, nausea, low red blood cells, low blood platelets and calcium levels, back pain, swelling of the lower legs or hands, upper respiratory tract infection, rash, and headache.

The most common side effects of Jubbonti, like Prolia, were low blood calcium; back, joint, arm, leg and muscle pain;, common cold (runny nose or sore throat), and arthritis.

The Jubbonti will be available through a Risk Evaluation and Mitigation Strategy (REMS) program, which is designed to inform prescribers and patients about the risk of severe hypocalcemia associated with the use Jubbonti in patients with advanced chronic kidney disease, including dialysis-dependent patients.

Denosumab is a human monoclonal antibody designed to bind to the RANKL protein, an activator of osteoclasts (cells involved in breaking down bone tissue). By binding to and inhibiting RANKL, denosumab decreases the production and activity of osteoclasts, resulting in a reduction of bone loss, and subsequently the likelihood of fractures and other serious bone conditions.

This story first appeared on Formulary Watch.