The U.S. Food and Drug Administration (FDA) has approved the supplemental Biologics License Application (sBLA) for denosumab to expand the currently approved indication for the prevention of skeletal-related events in patients with bone metastases from solid tumours to include patients with multiple myeloma.

The approval is based on data from the pivotal Phase 3 '482 study, the largest international multiple myeloma clinical trial ever conducted, which enrolled 1,718 patients

"Up to 40 percent of patients remain untreated for the prevention of bone complications, and the percentage is highest among patients with renal impairment at the time of diagnosis," said Noopur Raje, M.D., director, Center for Multiple Myeloma, Massachusetts General Hospital Cancer Center, Boston. "Denosumab, which is not cleared through the kidneys, offers multiple myeloma patients bone protection with a convenient subcutaneous administration, providing patients with a novel treatment option."

The '482 study was an international, Phase 3, randomized, double-blind, multicenter trial of denosumab compared with zoledronic acid for the prevention of skeletal-related events in adult patients with newly diagnosed multiple myeloma and bone disease.

In the study, a total of 1,718 patients (859 on each arm) were randomized to receive either subcutaneous denosumab 120 mg and intravenous placebo every four weeks, or intravenous zoledronic acid 4 mg (adjusted for renal function) and subcutaneous placebo every four weeks.

The study met the primary endpoint, demonstrating non-inferiority of denosumab to zoledronic acid in delaying the time to first on-study skeletal-related event in patients with multiple myeloma (HR=0.98, 95 percent CI: 0.85, 1.14; p=0.01).

The secondary endpoints, delaying time to first skeletal-related event and delaying time to first-and-subsequent skeletal-related events, did not demonstrate superiority.

Overall survival was comparable between denosumab and zoledronic acid, with a hazard ratio of 0.90 (95 percent CI: 0.70, 1.16; p=0.41).

The median difference in progression-free survival favored XGEVA by 10.7 months (HR=0.82, 95 percent CI: 0.68-0.99; descriptive p=0.036).

Median progression-free survival was 46.1 months (95 percent CI: 34.3 months, not estimable [NE], n=219) for denosumab and 35.4 months (95 percent CI: 30.2 months, NE, n=260) for zoledronic acid.

Adverse events observed in patients treated with XGEVA were generally consistent with the known safety profile of denosumab.

"Bone complications can be devastating for patients with multiple myeloma. Previously, treatment options for the prevention of bone complications were limited to bisphosphonates, which unlike XGEVA, are cleared by the kidneys," said David M. Reese, M.D., senior vice president of Translational Sciences and Oncology at Amgen. "We are pleased that the FDA has approved the expanded indication for XGEVA, providing a new option for patients and physicians, underscoring our commitment to advancing care for patients with multiple myeloma."

XGEVA is a fully human monoclonal antibody that binds to and neutralizes RANK ligand (RANKL) – a protein essential for the formation, function and survival of osteoclasts, which break down bone – thereby inhibiting osteoclast-mediated bone destruction.

XGEVA is currently the number one prescribed bone-targeting agent in the U.S. for the prevention of skeletal-related events in patients with bone metastases from solid tumours.

Additional regulatory applications for XGEVA for the prevention of skeletal-related events in patients with multiple myeloma are underway and have been submitted to health authorities worldwide.

Source: Amgen