FDA grants priority review to Xtandi for advanced prostate cancer

The FDA today granted priority review to enzalutamide for the treatment of chemotherapy-naive patients with metastatic castration-resistant prostate cancer, according to a press release issued by the drug’s manufacturers.

The FDA based its decision in part on results of the phase 3 PREVAIL trial, which included more than 1,700 patients with chemotherapy-naive disease who progressed during treatment with a luteinizing hormone-releasing hormone analogue or after bilateral orchiectomy.

Results of the randomized, double blind trial showed patients treated with enzalutamide (Xtandi; Astellas Pharma, Medivation) experienced improved OS and radiographic PFS compared with those who received placebo.

The most common adverse events associated with enzalutamide were asthenia/fatigue, back pain, diarrhea, arthralgia, hot flush, peripheral edema, musculoskeletal pain, headache, upper respiratory infection, muscular weakness, dizziness, insomnia, lower respiratory infection, spinal cord compression and cauda equina syndrome, hematuria, paresthesia, anxiety and hypertension.

Higher percentages of patients assigned enzalutamide experienced grade 1 to grade 4 neutropenia (15% vs. 6%), death from infections or sepsis (1% vs. 0.3%), falls or injuries related to falls (4.6% vs. 1.3%), and grade 1 or grade 2 hallucinations (1.6% vs. 0.3%).

An FDA decision on use of enzalutamide in this patient population is expected by Sept. 18.

Enzalutamide received FDA approval in August 2012 for the treatment of patients with metastatic castration-resistant prostate cancer who underwent prior treatment with docetaxel.