Enzalutamide 40 mg capsule, also known as Xtandi, is used to treat advanced prostate cancer, specifically metastatic castration-resistant prostate cancer. It acts as an androgen receptor inhibitor, preventing the activity of androgens such as testosterone, which can accelerate the growth of prostate cancer cells. By blocking these signals, Enzalutamide slows disease progression, increases survival rates, and relieves symptoms, considerably improving patients' quality of life.