ZYTIGA Phase 3 study for metastatic prostate cancer presented at 48th ASCO

Phase 3 Results Show Significant Improvement in Radiographic Progression-Free Survival and a Trend for Increased Overall Survival in Patients Receiving ZYTIGA® Plus Prednisone

New data presented this weekend at the 48^th annual meeting of the American Society of Clinical Oncology (ASCO) showed ZYTIGA® (abiraterone acetate) may prove to be an important new treatment option for metastatic prostate cancer patients prior to receiving chemotherapy. This is the first randomized study to demonstrate a radiographic progression-free survival benefit and an overall survival trend in this patient population.

The COU-AA-302 Phase 3 study investigated the use of ZYTIGA® plus prednisone compared to placebo plus prednisone in asymptomatic or mildly symptomatic patients with metastatic castration-resistant prostate cancer (mCRPC) who have not received chemotherapy.  The data demonstrated a statistically significant improvement in radiographic progression-free survival (rPFS) in the ZYTIGA® plus prednisone arm of the study compared to the placebo plus prednisone (control) arm.

"Great treatment advancements have been made in metastatic prostate cancer, which is exciting news for a patient population that until recently didn't have many treatment options," said Dr. Martin Gleave, British Columbia Leadership Chair, Professor and Distinguished University Scholar, Department of Urological Sciences, University of British Columbia, Director, The Vancouver Prostate Centre, University of British Columbia and one of the study's Canadian investigators. "The data announced at ASCO is important as it adds to the growing body of evidence supporting ZYTIGA®'s role for metastatic prostate cancer patients."

ZYTIGA® is an oral medication for prostate cancer.  In July 2011, ZYTIGA® was approved by Health Canada with prednisone for the treatment of men with metastatic prostate cancer (castration-resistant prostate cancer) who have received prior chemotherapy containing docetaxel. It is the first oral treatment that inhibits androgen production at all three sources - the testes, adrenal glands and in the tumour itself.