This is a multinational, multicenter, randomized (the study drug is assigned by chance), double-blind (neither physician nor patient knows the treatment that the patient receives), placebo-controlled (an inactive substance that is compared with a drug to test whether the drug has a real effect in a clinical trial) study. All patients will be randomly assigned in a 1:1 ratio between the abiraterone acetate group (abiraterone acetate and prednisone) and the placebo group (placebo and prednisone). The study will consist of a screening phase (within 28 days prior randomization on Cycle 1, Day 1), a treatment phase (28-day cycles until disease progression), and a follow-up phase (all patients will be contacted for every 3 months up to Month 60, focusing primarily on survival status). Patients will receive either abiraterone acetate 1,000 mg daily and prednisone 5 mg twice daily or placebo and prednisone 5 mg twice daily.
