Purpose: More than one-third of men may experience erectile dysfunction (ED) after nerve sparing radical retropubic prostatectomy. The efficacy and safety of vardenafil, a potent, selective, phosphodiesterase 5 inhibitor, was assessed for the treatment of ED after radical prostatectomy.
Materials and methods: In this double-blind study 440 men with ED after nerve sparing radical prostatectomy were randomized to take placebo, or 10 or 20 mg vardenafil. Efficacy was measured after 12 weeks using the erectile function domain of the International Index of Erectile Function, diary questions measuring vaginal penetration and intercourse success rates, and a global assessment question (GAQ) on erection.
Results: Of the intent to treat population 70% had severe ED (erectile function less than 11) at baseline. After 12 weeks both vardenafil doses were significantly superior to placebo (p <0.0001) for all efficacy variables. Improved erections (based on GAQ) were reported by 65.2% and 59.4% of patients on 20 and 10 mg vardenafil, respectively, and by only 12.5% of patients on placebo (p <0.0001). Among men with bilateral neurovascular bundle sparing, positive GAQ responses were reported by 71.1% and 59.7% of patients on 20 and 10 mg vardenafil, respectively, versus 11.5% of those on placebo (p <0.0001). The average intercourse success rate per patient receiving 20 mg vardenafil was 74% in men with mild to moderate ED and 28% in men with severe ED, compared to 49% and 4% for placebo, respectively. Few adverse events were observed. They were generally mild to moderate headache, flushing and rhinitis.
Conclusions: In men with severe ED after nerve sparing radical retropubic prostatectomy, vardenafil significantly improved key indices of erectile function.