SAN FRANCISCO (TheStreet) -- Medivation (MDVN - Get Report) and partner Astellas are stopping early a large phase III study of their prostate cancer drug Xtandi because patients are living significantly longer, the companies announced Tuesday.
With positive results from the phase III "Prevail" study, Medivation and Astellas will seek FDA and European approval to expand use of Xtandi to treat men with advanced prostate cancer who have not yet received chemotherapy. This so-called "pre-chemo" prostate cancer patient population has the potential to turn Xtandi into a blockbuster drug.
Medivation shares rise 9% to $54.40 in pre-market trading.
Based on an interim analysis of the Prevail study, prostate cancer patients treated with Xtandi had a 30% reduction in the risk of death compared to patients treated with a placebo. The survival benefit was statistically significant.