Enzalutamide marks the latest addition to the drugs currently approved by the US Food and Drug Administration for metastatic,castration-resistant prostate cancer (mCRPC).AFFIRM was a phase Ⅲ international randomized trial that evaluated the clinical utility of enzalutamide versus placebo in men with mCRPC who have failed prior docetaxel-containing chemotherapy.Enzalutamide showed a remarkable 37％ decreased risk of death with a median overall survival of 18.4 months versus 13.6 months for those who received placebo.These findings confirm the validity of further targeting the androgen receptor as a valid therapeutic approach in prostate cancer despite emergence of castration resistance.