Yesterday, Amgen announced that it had submitted a supplemental Biologics License Application (sBLA) to the U.S. Food and Drug Administration (FDA) to expand its license for XGEVA® (denosumab) to treat men with castrate-resistant prostate cancer to reduce the risk of developing bone metastases. If approved, XGEVA would be the first therapy licensed to prevent or delay the spread of cancer to the bone.

The sBLA submission is based on a pivotal Phase 3 Study (‘147) evaluating XGEVA versus placebo in 1,432 men with castrate-resistant prostate cancer. Results of the ‘147 study demonstrate that XGEVA significantly prolonged bone metastasis-free survival by more than four months compared with placebo (29.5 versus 25.2 months, respectively) in men with castrate-resistant prostate cancer that had not yet spread to the bone. Bone metastasis-free survival is a composite measure of the development of bone metastases or death.

“The successful outcome of this study provides clinical evidence supporting the view that tumors activate the RANK Ligand pathway to penetrate bone,” said Roger M. Perlmutter, M.D., Ph.D., executive vice president of Research and Development at Amgen. “XGEVA has the potential to become a significant advance for patients with castrate-resistant prostate cancer who currently have no treatment options to help prevent the spread of cancer to their bones.”

In men with prostate cancer, bone is the most common places for cancer to spread. Up to 90 percent of men with advanced prostate cancer will have their tumor spread to the bone.

In the ‘147 trial, adverse events and serious adverse events were relatively similar between the XGEVA and placebo arms. Hypocalcemia (low serum calcium levels in the blood) and osteonecrosis of the jaw (ONJ) were reported with increased frequencies in the XGEVA treated patients. The yearly rate of ONJ in the XGEVA arm was similar to prior XGEVA trial results. Back pain was the most common adverse event reported in the XGEVA arm of the trial.

Joel T Nowak, M.A., M.S.W.