Thalidomide/estramustine/paclitaxel in metastatic androgen-independent prostate cancer

This is a phase I/II trial of thalidomide with estramustine and paclitaxel in men with androgen-independent prostate cancer (AIPC) who underwent previous chemotherapy.

Men with progressive AIPC were treated with oral thalidomide (200 mg, 400 mg, or 600 mg daily), intravenous paclitaxel (100 mg/m2 over 3 hours on days 3 and 10), and oral estramustine (140 mg 3 times daily on days 1-5 and days 8-12) every 21 days.

Phase I: first cycle dose-limiting toxicity occurred in 0 of 3 patients at 200 mg thalidomide daily, 0 of 3 at 400 mg daily, and 1 of 3 at 600 mg daily (the designated maximum tolerated dose). Phase II: twenty-nine of 38 evaluable patients (76%; 95% confidence interval, 67%-87%) experienced a 50% decrease in prostate-specific antigen level. Five of 18 patients (28%) with measurable disease exhibited an objective response. Nine of 14 patients (64%) with disease refractory to previous taxane therapy had 50% decreases in prostate-specific antigen level. Grade 3/4 adverse events included neutropenia (9 of 39 [23%]), fatigue (9 of 39 [23%]), dyspnea (8 of 39 [21%]), and thromboembolic events (7 of 39 [18%]). Cumulative dose-limiting toxicity rates were minimal (13%) with thalidomide at 200 mg daily.

The profile of activity of thalidomide/paclitaxel/estramustine in taxane-refractory AIPC warrants further investigation.