An orally active acetate salt of the steroidal compound abiraterone with antiandrogen activity. Abiraterone inhibits the enzymatic activity of steroid 17alpha-monooxygenase (17alpha-hydrolase/C17,20 lyase complex), a member of the cytochrome p450 family that catalyzes the 17alpha-hydroxylation of steroid intermediates involved in testosterone synthesis. Administration of this agent may suppress testosterone production by both the testes and the adrenals to castrate-range levels. or A drug used with prednisone to treat prostate cancer that has spread to other parts of the body and has not gotten better with other hormone therapy. It is also being studied in the treatment of other types of cancer. Abiraterone acetate 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. Also called Zytiga.