This is a Phase 4, non-randomized, multi-center (when more than one hospital work on a medical research study), open label (identity of study drug will be known to participant and study staff), single arm study of abiraterone acetate to investigate its efficacy and safety in participants with metastatic castration-resistant prostate cancer (mCRPC) who failed the first-line combined androgen blockade (CAB) therapy. The study consists of Screening Phase (28 days prior to Cycle 1 Day 1), Treatment Phase (up to 2 years), Post Treatment Phase (30 days after the last dose of study drug). Participants will receive 1000 milligram (mg) (four 250 mg tablets) of abiraterone acetate orally once daily. In addition, 5 mg of oral prednisolone will be concomitantly administered twice a day (10 mg per day). A 28-daily dosing cycle will be continued until disease progression or unacceptable toxicity is observed. The total duration of study will be 2 years. Participants will be primarily evaluated for PSA response. Participants' safety will be monitored throughout the study.
