PSD502 is a novel aerosolized, lidocaine-prilocaine, spray being developed for the treatment of lifelong premature ejaculation. The clinical profile of PSD502 is described in one of two double-blind, placebo-controlled, phase III studies.To determine the effect of PSD502 on the Index of Premature Ejaculation (IPE) and intravaginal ejaculatory latency (IELT) of men with lifelong PE.Men with lifelong PE who documented an IELT ≤ 1 minute with two or more of the first three sexual encounters during a 4-week baseline period were randomized to receive double-blind treatment with PSD502 or placebo for 3 months. Patients completed IPE and Premature Ejaculation Profile questionnaires at entry and monthly visits, and recorded stop-watch timed IELT during each encounter. Safety was assessed by collecting adverse event data and standard safety measures.Stopwatch timed IELT recordings and a patient-reported outcome questionnaire the IPE were used in this study to determine the effect of PSD502 applied topically 5 minutes before intercourse.Two hundred fifty-six men with PE were randomized from 38 centers in the U.S., Canada, and Poland. The geometric mean IELT over the 3-month treatment period increased from a baseline of 0.56 minute and 0.53 minute in the PSD502 and placebo group respectively to 2.60 and 0.80 minute. There were significantly greater increases in the scores for the IPE domains of ejaculatory control, sexual satisfaction and distress in the PSD502 group than in the placebo group, with a mean 5.0 point difference between treatments in change from baseline in the IPE domain for ejaculatory control, 4.6 point difference in change from baseline in the IPE domain for sexual satisfaction, and a 2.5 point difference in change from baseline in the IPE domain for distress. This was supported by improvements in all secondary endpoints.In this study, PSD502 applied topically to the glans penis 5 minutes before intercourse showed significantly improved ejaculatory latency, ejaculatory control, sexual satisfaction and distress and was shown to be well tolerated by patients and partners.