FDA has rubber-stamped Centocor Ortho Biotech’s Zytiga™ (abiraterone acetate) as combination therapy with prednisone for the treatment of metastatic castration-resistant prostate cancer in men who have received prior docetaxel-based chemotherapy.
Approval in the U.S. was based on data from a 1,195-patient Phase III trial (COU-AA-301), which demonstrated that the combination of oral, once-daily Zytiga and prednisone led to a 35% reduction in the risk of death and a 3.9 month improvement in median survival compared with prednisone therapy alone.
Zytiga is an oral androgen biosynthesis inhibitor designed to block the CYP17 enzyme complex required for production of androgen in the testes, adrenal glands, and in the prostate in prostate cancer patients. The FDA application, submitted in December, was given priority review status. Also in December partner Janssen-Cilag filed a marketing authorization application for abiraterone acetate with the European Medicines Agency. Under terms of the firms’ deal for Zytiga, abiraterone acetate will be commercialized and distributed by Centocor Ortho Biotech in the U.S. and, pending relevant approvals, by Janssen Pharmaceutical companies in all other global markets.