The effectiveness and safety of avanafil for erectile dysfunction: a systematic review and meta-analysis

Objective: To compare the efficacy and safety between different dosages of avanafil for the treatment of erectile dysfunction (ED). Methods: PubMed, Cochrane Library, and Embase were searched to identify randomized controlled trials which compared avanafil with placebo, or compared different dosages of avanafil for ED. International Index of Erectile Function Erectile Function domain score (IIEF-EF), Sexual Encounter Profile Question (SEP) questions 2 and 3, and adverse events were considered as the study outcomes. Both pairwise meta-analysis and network meta-analysis were carried out. Results: Five studies including 2225 patients were assessed. The pairwise meta-analysis suggested that avanafil was more effective than placebo in improving IIEF-EF (mean difference [MD]: 4.47; 95% confidence interval [CI]: 3.51 to 5.43), SEP-2 (MD: 17.41; 95% Cl: 14.03 to 20.79), and SEP-3 (MD: 20.01; 95% CI: 22.98 to 37.22), with an evident dose response relationship. The effectiveness was significantly different between the 50 mg and 100 mg groups, or between the 50 mg and 200 mg groups, for all outcomes. Overall, avanafil was associated with a significantly higher incidence of any adverse event (risk ratio [RR]: 2.56; 95% Cl: 1.66 to 3.94), serious adverse event (RR: 2.78; 95% CI: 1.34 to 5.76), flushing (RR: 6.06; 95% CI: 3.37 to 10.88) and headache (RR: 7.54; 95% CI: 3.52 to 16.12) when compared with placebo. No significant difference in safety was found among various dosage groups. Conclusions: Avanafil, from 50 to 200 mg, is effective and well tolerated for the treatment of ED, and an increase in dosage is associated with a significant rise in effectiveness but not with significantly more adverse events.