US FDA approves Amgen’s Xgeva for rare bone condition

The US FDA has expanded the approved use of Amgen's Xgeva to treat giant cell tumor of the bone (GCTB), which is a rare and usually non-cancerous tumor. The regulatory body also granted Xgeva with orphan product designation, because it is intended to treat a rare disease.

Xgeva (denosumab) is a monoclonal antibody that binds to RANKL, a protein essential for maintenance of healthy bone. RANKL is also present in GCTB. Xgeva is intended for patients whose GCTB cannot be surgically removed or when surgery is likely to result in severe morbidity, such as loss of limbs or joint removal. It should only be used in adolescents whose bones have matured.

"With today's XGEVA FDA approval, Amgen can offer a much needed treatment option to patients who suffer from giant cell tumor of bone that cannot be adequately treated with surgery. Advances in our understanding of the underlying biology of this rare disorder have allowed Amgen to generate compelling clinical evidence to address the medical needs of patients and their healthcare providers."

Sean E. Harper, M.D., executive vice president of Research and Development at Amgen.

The FDA reviewed Xgeva under its priority review program, which provides for an expedited review of drugs. The approval was based on positive results from two clinical trials that enrolled patients with GCTB that was either recurrent or for which planned surgery was likely to result in severe morbidity. The overall objective response rate of the 187 patients evaluated was 25%.

Xgeva was previously approved in 2010 to prevent fractures when cancer has spread to the bones.