AURORA, Colo., Aug. 17 (UPI) -- A phase III trial of the drug Enzalutamide extended the life of advanced prostate cancer patients by an average of five months, U.S. researchers found.
Study co-author Dr. Thomas Flaig, medical director of the University of Colorado Cancer Center's Clinical Investigations Shared Resource and the University of Colorado School of Medicine, said the study involved 1,199 patients with prostate cancer that had progressed despite both hormonal and chemotherapy treatments.
Two-thirds of the patients received the drug versus a control group that received a placebo,
The study, published in the New England Journal of Medicine, found the median overall survival for patients in the treatment arm of the trial was 18.4 months compared to 13.6 months for patients in the placebo arm.
In addition to prolonged survival, patients given Enzalutamide showed meaningful improvement in other measures -- including prostate-specific antigen blood levels, an increase from three months to 8.3 months in time until PSA progression, and an increase from 2.9 months to 8.3 months in overall progression-free survival, the study found.
The once-a-day oral drug works by blocking prostate cancer's ability to supply itself with androgens -- hormones including testosterone that otherwise drive the cancer's growth.
"This is a major advance. Not only do we see more survival benefit than from traditional chemotherapy, but the side effects of Enzalutamide are much lower," Flaig said in a statement. "It provides both more benefit and less harm."