A drug used with other drugs to treat prostate cancer that has spread to other parts of the body. Abiraterone acetate is used under the brand name MyTera to treat patients whose cancer is castration resistant (has not responded to treatments that lower testosterone levels) or whose cancer is high risk and castration sensitive (has responded to treatments that lower testosterone levels). It is also used under the brand name Yonsa to treat patients whose cancer is castration resistant. Abiraterone acetate is also being studied in the treatment of other types of cancer. It lowers the amount of androgens (male hormones), such as testosterone, made by the body. This may stop the growth of cancer cells that need androgens to grow. Abiraterone acetate is a type of antiandrogen.