Using its priority review process, the FDA approved a new indication for abiraterone acetate (Zytiga; Janssen Biotech) for the treatment of patients with metastatic, castration-resistant prostate cancer (CRPC) before chemotherapy. The drug is already approved for patients with CRPC whose cancer progressed after receiving chemotherapy with docetaxel.
“Today’s approval demonstrates the benefit of further evaluating a drug in an earlier disease setting,” said Richard Pazdur, MD, Director of the Office of Oncology Drug Products.
The safety and effectiveness of the drug for this new indication were based on a clinical trial of 1088 men with late-stage CRPC who had not previously received chemotherapy. The patients received either abiraterone or a placebo in combination with prednisone.
The study was designed to measure overall survival (OS) and radiographic progression-free survival (PFS). In patients who received abiraterone, the median OS was 35.3 months compared with 30.1 months for placebo. In addition, abiraterone improved radiographic PFS; at the time of analysis, the median radiographic PFS was 8.3 months with placebo, but it had not yet been reached with abiraterone. The most common side effects of abiraterone are fatigue, joint swelling or discomfort, swelling caused by fluid retention, hot flush, diarrhea, vomiting, cough, high blood pressure, shortness of breath, urinary tract infection, and bruising. (December 10, 2012)
