Amgen announces primary results from XGEVA Phase 3 trial in castrate-resistant prostate cancer

Amgen (NASDAQ: AMGN) today announced primary results of a pivotal Phase 3 trial ('147) demonstrating that XGEVA™ (denosumab) significantly increased bone metastasis-free survival for more than four months in men with castrate-resistant metastatic prostate cancer that has not yet spread to bone. Full results of the '147 study were presented for the first time today in a late-breaking plenary session at the American Urological Association (AUA) 2011 Annual Meeting in Washington, D.C.

With effective therapies now in place for both early (castrate-sensitive) prostate cancer and advanced (castrate-resistant) prostate cancer, there is a gap in the treatment plan for those patients who are castrate-resistant but have not yet developed metastatic disease.  Bone is the most common place for prostate cancer to spread; up to 90 percent of men with prostate cancer will experience bone metastases.

The data showed that XGEVA significantly improved median bone metastasis-free survival by 4.2 months, a risk reduction of 15 percent, compared with placebo (29.5 versus 25.2 months, respectively; hazard ratio [HR] 0.85; 95 percent CI: 0.73, 0.98.

"In this landmark Phase 3 study, XGEVA  increased bone metastasis-free survival by preventing bone metastases in men with castration-resistant prostate cancer," said Matthew Smith, M.D., Ph.D., director of the Genitourinary Malignancies Program at Massachusetts General Hospital Cancer Center, Boston.  "XGEVA is the first and only bone targeted therapy that has demonstrated the ability to significantly reduce the risk of bone metastasis in men with prostate cancer."  

In the '147 trial, adverse events and serious adverse events were relatively similar between the XGEVA and placebo arms. Hypocalcemia 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.