A randomized, double-blind, placebo-controlled evaluation of the safety and efficacy of avanafil in subjects with erectile dysfunction

Introduction: Phosphodiesterase type 5 (PDE5) inhibitors have become standard treatment for erectile dysfunction (ED).

Aim: To prospectively evaluate the safety and efficacy of avanafil, a novel PDE5 inhibitor, in men with mild to severe ED.

Methods: In this multicenter, double-blind, Phase 3 trial, 646 subjects were randomized to receive avanafil (50 mg, 100 mg, 200 mg) or placebo throughout a 12-week treatment period. Subjects were instructed to take study drug 30 minutes prior to initiation of sexual activity. At least a 12-hour separation time between doses was required; no restrictions were placed on food or alcohol intake.

Main outcome measures: Improvement in erectile function (EF) was measured by Sexual Encounter Profile questions 2 and 3 (SEP2 and SEP3) and by the EF domain of the International Index of Erectile Function (IIEF) questionnaire.

Results: Mean change in percentage of successful sexual attempts (SEP2 and SEP3) and IIEF-EF domain score significantly favored all doses of avanafil over placebo (P ≤ 0.001). Secondary analyses demonstrated achievement of successful intercourse by subjects within 15 minutes of dosing. Of the 300 sexual attempts made during this interval, 64% to 71% were successful in avanafil-treated subjects compared with 27% in placebo-treated subjects. Successful intercourse was also demonstrated >6 hours post dosing, with 59% to 83% of the 80 sexual attempts successful in avanafil-treated subjects compared with 25% of placebo-treated subjects. The most commonly reported adverse events in subjects taking avanafil included headache, flushing, and nasal congestion; there were no drug-related serious adverse events.

Conclusion: Following 12 weeks of avanafil treatment without food or alcohol restrictions, significant improvements in sexual function were observed with all 3 doses of avanafil compared with placebo. Successful intercourse was observed as early as 15 minutes and >6 hours after dosing in some subjects. Avanafil was generally well tolerated for the treatment of ED.