FDA Approves Enzalutamide for Castration-Resistant Prostate Cancer
Posted: Wednesday, July 18, 2018
On July 13, 2018, the U.S. Food and Drug Administration (FDA) approved enzalutamide (Xtandi) for patients with castration-resistant prostate cancer. This approval broadens the indicated patient population to include patients with both nonmetastatic and metastatic castration-resistant prostate cancers. Enzalutamide was previously approved for the treatment of patients with metastatic castration-resistant prostate cancer.
Approval in patients with nonmetastatic castration-resistant prostate cancer was based on the randomized, multicenter PROSPER clinical trial, which randomized 1,401 patients to receive either enzalutamide or placebo orally once daily. Patients continued on gonadotropin-releasing hormone therapy or had prior bilateral orchiectomy. The trial demonstrated a statistically significant improvement in metastasis-free survival for patients receiving enzalutamide compared with those receiving placebo, with a median metastasis-free survival of 36.6 and 14.7 months, respectively.
The most common adverse reactions (≥ 10%) that occurred more frequently (≥ 2% over placebo) in the enzalutamide-treated patients in the PROSPER trial were asthenia/fatigue, hot flush, hypertension, dizziness, nausea, and falls. Grade 3 or higher adverse reactions were reported in 31% of men treated with enzalutamide plus androgen-deprivation therapy and in 23% of men treated with androgen-deprivation therapy alone.
Data from the PROSPER trial were recently published in The New England Journal of Medicine.