SAN FRANCISCO (EGMN) - The survival benefit seen with the cell-based sipuleucel-T vaccine in men with metastatic, castration-resistant prostate cancer persists in the longer term, according to updated results of the randomized, double-blind, phase III IMPACT trial.With a median follow-up of more than 3 years, patients who were given the sipuleucel-T (Provenge) vaccine lived an average of 4.1 months longer than their counterparts who were given a placebo, researchers reported at a symposium on genitourinary...