enzalutamide

Enzalutamide is a non-steroidal antiandrogen used in the management of prostate cancer. It acts as an antagonist of the androgen receptor (AR), inhibiting AR signaling by blocking androgen binding, preventing AR from translocating to the nucleus, and inhibiting DNA binding and transcriptional activity. This leads to reduced growth of prostate cancer cells that rely on AR signaling.

Indications: It is approved for metastatic castration-resistant prostate cancer (mCRPC) in men who have previously received androgen deprivation therapy (ADT). It is also approved for nonmetastatic CRPC at high risk of metastasis and, in combination with ADT, for metastatic hormone-sensitive prostate cancer.

Administration: Enzalutamide is taken orally, typically 160 mg once daily (two 80 mg capsules), with or without food.

Safety and adverse effects: Common adverse effects include fatigue, hot flashes, hypertension, edema, dizziness, diarrhea, and nausea. Seizures have been reported rarely; cognitive impairment or falls can occur. Liver injury has been observed, so liver function testing is advised as indicated.

Interactions and pharmacology: Enzalutamide induces several cytochrome P450 enzymes (notably CYP3A4, CYP2C9, and CYP2C19) and is a substrate of CYP2C8, which can alter levels of other drugs such as warfarin and certain statins. Concomitant use with drugs that lower seizure threshold or with strong CYP inducers requires caution and possible dose adjustments or monitoring.