Abiraterone Acetate (Zytiga) and enzalutamide (Xtandi) are the newest generation hormonal agents.  They both have demonstrated a survival advantage in men with castrate resistant prostate cancer (CRPC) who have already been treated with docetaxel (chemotherapy). Unfortunately all men who are responsive to both of these drugs eventually become resistant.   Some men are subject to early progression (failure) within the first 3 months of the treatment.  This leads to an early treatment interruption.

In an analysis of the situation researchers have tried to identify which factor, if any, may predict this early failure of either of these drugs.

The researchers evaluated a consecutive series of 57 men (a small sample) treated between September 2011 and March 2013 . Twenty-six men received Zytiga  (1,000 mg po +