Improvement in Duration of Erection with Vardenafil treatment in Men with Erectile Dysfunction: findings of the Endurance Study

Inclusion criteria: men aged 18–64 years; ED >6 months‟ duration; International Index of Erectile Function, erectile function domain (IIEF-EF) score >5 and <26. Patients completed a 4-week runing period and were then randomised to 4 weeks‟ treatment with fixed-dose vardenafil 10 mg or placebo. After a 1-week washout period, patients were crossed over to the alternate study medication. Primary efficacy measure: stopwatch-assessed duration of erection (measured from time erection perceived hard enough for penetration until withdrawal from partner‟s vagina) leading to successful intercourse (measured by Sexual Encounter Profile question 3 [SEP3]). Secondary efficacy measures included: IIEF-EF, SEP2 and SEP3.
Intent-to-treat (ITT) population = 191 patients. Patients had ED of varying aetiology and severity (moderate/severe ED, 73%). Baseline underlying conditions included hypertension (32%), diabetes (7%) and hyperlipidemia (10%).

Over 4 weeks‟ treatment, least squares mean duration of erection leading to successful intercourse was significantly longer for vardenafil than for placebo (12.81 min vs 5.45 min; p<0.001). Treatment with vardenafil was also superior to placebo in IIEF-EF, SEP2 and SEP3 measures. Vardenafil was well tolerated; the nature and incidence of adverse events were consistent with the previously demonstrated safety profile of vardenafil. Compared with placebo, vardenafil treatment produced a significantly superior duration of erection leading to successful intercourse in men with ED of broad aetiology.