Safety and efficacy of dapoxetine in the treatment of premature ejaculation: a double-blind, placebo-controlled, fixed-dose, randomized study

Abstract

The aim of the study was to evaluate the efficacy and safety of a selective serotonin reuptake inhibitor (SSRI) drug dapoxetine in delaying ejaculation in patients with premature ejaculation (PE). A total of 212 potent men with PE were randomly assigned to receive 30 mg orally dapoxetine (group 1, N=106) twice daily or similar regimen of placebo (group 2, N=106) during a 12-week period for each agent. Pretreatment evaluation included history and physical examination, geometric mean intravaginal ejaculatory latency time (IELT, primary outcome measure), and International Index of Erectile Function (IIEF). The efficacy of two treatments was assessed every 2 weeks during treatment, at the end of study, and in 3-month follow-up after cessation of treatment. We measured geometric mean IELT. Thus, the IELT values were logarithmically transformed before statistical analysis, and the results are reported as fold increases from baseline with associated 95% confidence intervals (CI). The independent sample two-tailed t-test was used to compare the IELTs. At the end of 12-week treatment, the dapoxetine group had a 2.9- (95% CI, 1.84-4.16) fold increase of the geometric mean IELT, while after placebo the geometric mean IELT did not increase significantly (1.4-fold increase; 95% CI, 0.84-1.63) (p=0.001). The mean weekly intercourse episodes increased from pretreatment values of 1.16 and 1.14 to 2.2 and 1.4, for dapoxetine and placebo, respectively (p=0.04). Baseline mean intercourse satisfaction domain values of IIEF, 12 and 11, reached to 16 and 10 at the 12-week treatment in groups 1 and 2, respectively (p=0.04). At the end of 3-month follow-up period, the geometric mean IELT in dapoxetine and placebo group demonstrated 1.4- (95% CI, 0.66-1.46) and 1.3- (95% CI, 0.77-1.63) fold increase, respectively (p=0.1). Three-month intercourse satisfaction domain value of IIEF was 11 in group 1 and 10 in group 2 (p=0.1). Mean number of adverse events was 19 for dapoxetine and 7 for placebo (p=0.02). Dapoxetine has moderately better results in terms of IELT and intercourse satisfaction vs placebo without long-term benefit for the patient after it is withdrawn. Further studies are necessary to draw final conclusions on the efficacy of this drug in PE.