Enzalutamide

Enzalutamide is an androgen receptor (AR) inhibitor for the treatment of castration-resistant prostate cancer (CRPC), both metastatic and non-metastatic. It is a second-generation antiandrogen agent that the FDA approved on August 31, 2012. Although androgen deprivation therapy (ADT) is the first-line treatment of prostate cancer and remission can be achieved, arising resistance is inevitable, becoming castration-resistant prostate cancer. Until recently, docetaxel is the only treatment available for metastatic CRPC; however, AR inhibitors have been developed for more targeted therapy, although first-generation AR inhibitors like bicalutamide did not substantially increase the survival rate. Second-generation such as enzalutamide is more efficacious due to a higher affinity to AR and no partial agonist activity compared to bicalutamide.

Due to a favorable pharmacological profile, a phase 1 study of enzalutamide was initiated in July 2007. Compared to the average time of 10 to 15 years for a drug to go from pre-clinical to clinical studies, enzalutamide was developed relatively rapidly.