On April 28, 2011, the US Food and Drug Administration approved abiraterone acetate (Zytiga) in combination with prednisone for the treatment of metastatic, advanced prostate cancer in men who have received prior chemotherapy. Howard I. Scher, Chief of Memorial Sloan-Kettering's Genitourinary Oncology Service, was one of the principal investigators of the international clinical trials leading to the drug's approval. His colleagues at Memorial Sloan-Kettering also played a critical role in the research. Abiraterone is a pill taken once a day and will add to a growing arsenal of drugs to treat advanced prostate cancer. Dr. Scher sat down with us to answer some key questions about the new drug, how it works, and how it will impact the treatment of men with advanced prostate cancer.