LOS ANGELESCougar Biotechnology, Inc.'s CB7630 (abiraterone acetate) was well tolerated at doses as high as 2,000 mg/d with minimal toxicity in a phase I/II trial of chemotherapy-naive patients with castration-refractory prostate cancer, who had progressive disease despite treatment with LHRH analogs and multiple other hormonal therapies. Of 30 evaluable patients, 18 (60%) had a confirmed decline in PSA of greater than 50%, while 10 (33%) had declines greater than 90%. Of 20 evaluable patients with measurable lesions, 11 (55%) had a partial radiological response, while 7 had ongoing stable disease and 3 had regressing bone disease. The data were presented at the American Urological Association (AUA) annual meeting.
