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 less than or equal to0.004) 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.