Abiraterone, a new drug for prostate cancer  patients whose tumors have continued to grow despite medical or surgical castration has been shown to inhibit production of male hormones is showing promise in early trials.   

The drug reduces levels of "prostate specific antigen", a marker of cancer activity, and shrinks tumors in patients in whom hormone therapy had stopped working and also in patients who have previously been treated with chemotherapy.The success rate is as much as 80%.

The drug is expected to be on the market within 3 years.