The FDA (U.S. Food and Drug Administration) recently approved abiraterone in combination with prednisone for the pre-chemotherapy treatment of prostate cancer patients. Abiraterone acetate is a selective inhibitor of androgen synthesis that blocks androgen synthesis in the adrenal glands, testes, and tumor cells by blocking cytochrome P450c17 (CYP17, a key enzyme in testosterone synthesis). In its Phase 1 and 2 clinical trials, abiraterone acetate had a very significant anti-cancer effect in patients with progressive destructive resistant prostate cancer. In the current phase 3 trial, the use of abiraterone acetate and prednisone to inhibit androgen synthesis was shown to improve the overall survival of patients with advanced prostate cancer. Nearly 1,200 patients with advanced prostate cancer who had received polyene paclitaxel chemotherapy as part of their prior treatment were enrolled in the trial. They were given prednisone twice daily along with the trial drug (abiraterone acetate) or placebo. The primary observed endpoint of the trial was overall survival, and secondary observed endpoints included time to PSA re-elevation, survival without disease progression, and PSA response rate. After a mean follow-up of one year, the overall survival rate was significantly higher in the trial group than in the placebo group, and the mean survival time was 4 months longer than in the placebo group. The trial group still had significant advantages in the secondary observed endpoints of time to PSA re-elevation, disease-free survival, and PSA response rate.