A hormone-blocking pill approved last year for some men with advanced prostate cancer now also seems to help a wider group of men who were given it sooner in the course of treating their disease.
A study of Johnson & Johnson's Zytiga found that the drug doubled the time that men lived without their cancer getting worse.
The drug also seems to be improving survival, but it will take longer follow-up to know for sure.
Independent monitors stopped the study once it was clear the drug was helping and let men who had been getting dummy pills switch to Zytiga.
The drug blocks testosterone, a hormone that helps prostate cancer grow. The study was discussed Saturday at a cancer conference in Chicago.