The U.S. Food and Drug Administration today, August 31, 2012 approved Xtandi® (MDV3100) (enzalutamide) capsules to treat men with late-stage (metastatic) castration-resistant prostate cancer that has spread or recurred, even with medical or surgical therapy to minimize testosterone.

Approved for prostate cancer patients previously treated with chemotherapy, Xtandi was reviewed under the FDA’s priority review program.

The approval was based on a single randomized, placebo-controlled, multicenter trial enrolling 1199 patients with metastatic castration-resistant prostate cancer who had received prior docetaxel. Patients were randomly allocated to receive enzalutamide 160 mg orally once daily (N = 800) or placebo (N = 399). Study treatment continued until disease progression, initiation of new systemic antineoplastic treatment, unacceptable toxicity, or withdrawal. Patients were required to continue androgen deprivation therapy and were allowed, but not required, to continue or initiate glucocorticoids during the study period.

The primary efficacy endpoint of the clinical trial was overall survival (OS). At the pre-specified interim analysis after 520 events, a statistically significant improvement in OS

[HR 0.63 (95% CI: 0.53, 0.75), p < 0.0001, log rank test] was observed. The median OS was 18.4 and 13.6 months in the enzalutamide and placebo arms, respectively, or an increased survival advantage of 4.8 months.XTANDI is an oral, once-daily androgen receptor inhibitor. The recommended dose of XTANDI is 160 mg (four 40 mg capsules) administered orally once daily. XTANDI can be taken with or without food and does not require concomitant steroid (e.g., prednisone) use.Joel T Nowak, M.A., M.S.W.[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]