Abnormal epidermal growth factor receptor expression and pre-clinical data prompted us to investigate the activity of gefitinib, a selective epidermal growth factor receptor tyrosine kinase inhibitor, in hormone-refractory prostate cancer. Eighty-two patients were randomly assigned to receive prednisone plus gefitinib (pG; n = 44) or prednisone plus placebo (ppl; n = 38). On progression, patients initially assigned to placebo were offered the possibility to receive gefitinib. Best prostate-specific antigen response was the primary endpoint. At a median follow-up time of 29.0 months (26.0-32.0), 77 patients progressed and 51 died. Prostate-specific antigen response was recorded in 6/38 (15.8%; 95% CI 4.2-27.4) and in 5/44 (11.4%; 95% CI 2.0-20.8) patients in pG and ppl groups, respectively. There was no difference between groups in time to progression (median pG 4.0 months, range 3.5-4.5; median ppl 4.5 months, range 3.5-5.0) and survival (median pG 26.5 months, range 16.0-37.0; median ppl 20.5 months, range 14.0-27.0). Adverse events occurred in 19 patients in each arm and were generally mild. pG showed a good tolerability profile but only a limited therapeutic activity in hormone-refractory prostate cancer. (c) 2008 S. Karger AG, Basel.