Randomized study of testosterone gel as adjunctive therapy to sildenafil in hypogonadal men with erectile dysfunction who do not respond to sildenafil alone

PURPOSE: We compare the efficacy of testosterone gel (T-gel) versus placebo as adjunctive therapy to sildenafil in hypogonadal men with erectile dysfunction who do not respond to sildenafil alone. MATERIALS AND METHODS: A randomized, placebo controlled, double-blind, parallel group, multicenter study was performed. A total of 75 hypogonadal men (18 to 80 years old, morning serum total testosterone 400 ng/dl or less) with confirmed lack of response to sildenafil monotherapy were randomized (1:1) to receive a daily dose of 1% T-gel or 5 gm placebo gel as adjunctive therapy to 100 mg sildenafil during a 12-week period. Subjects were evaluated for sexual function, primarily based on the International Index of Erectile Function (IIEF), quality of life and serum testosterone levels at baseline and weeks 4, 8 and 12. RESULTS: Testosterone treated subjects had greater improvement in erectile function compared to those who received placebo, reaching statistical significance at week 4 (4.4 vs 2.1, p = 0.029, 95.1% CI 0.3, 4.7). Similar trends were observed for improvements in orgasmic function, overall satisfaction, total IIEF score and percentage of IIEF responders. T-gel significantly (p < or =0.004) increased total and free testosterone levels throughout the study, although no significant correlations were made between testosterone levels and the IIEF at end point. CONCLUSIONS: T-gel taken with sildenafil may be beneficial in improving erectile function in hypogonadal men with erectile dysfunction who are unresponsive to sildenafil alone.