THOUSAND OAKS, Calif. — A cancer drug made by Amgen reduced the chances of prostate cancer spreading to the bones, according to results of a late-stage clinical trial presented at the American Urological Association’s annual meeting in Washington.

The phase-3 “Study ‘147” of Xgeva (denosumab) showed that men taking the drug survived for four months longer without the cancer spreading to their bones, compared with those taking placebo.

The study enrolled 1,432 men with prostate cancer that persisted despite castration but had not spread to the bones — known as bone metastasis — who were administered Xgeva or placebo. Study data showed that Xgeva reduced the risk of bone metastases by 15%, compared with placebo.