Dinsmore, W. W. & Wyllie, M. G. PSD502 improves ejaculatory latency, control and sexual satisfaction when applied topically 5 min before intercourse in men with premature ejaculation: results of a phase III, multicentre, double-blind, placebo-controlled study. BJU Int. 103, 940–949 (2009).

A new topical spray—PSD502—for the treatment of premature ejaculation has shown promising results. “Our study shows that when the PSD502 spray was applied to the man's penis 5 min before intercourse, it improved both sexual performance and sexual satisfaction, which are key factors in treating premature ejaculation,” says lead researcher W. Wallace Dinsmore from the Royal Victoria Hospital, Belfast, UK.

Topical anesthetic creams containing lidocaine and prilocaine are often recommended for treating premature ejaculation; however, these creams are not specifically designed to help with this condition, and may need to be applied to the penis long before intercourse. PSD502 contains the same active ingredients, but in a convenient spray form. Dinsmore and Wyllie investigated the effect of PSD502 on the index of premature ejaculation and intravaginal ejaculatory latency time (IELT) in men with lifelong premature ejaculation, and assessed the safety and tolerability of the spray in the men and their sexual partners.

The researchers recruited 300 men (aged >18 years) clinically diagnosed as having premature ejaculation with an IELT of ≤1 min (mean IELT at baseline 0.6 min). Patients were randomly assigned to receive either PSD502 spray (7.5 mg lidocaine, 2.5 mg prilocaine; 200 men) or placebo spray (100 men) for 3 months. The men were instructed to spray the solution onto the glans penis 5 min before intercourse. After penetration, time to ejaculation was measured by the men or their partners using a stopwatch.

Men treated with PSD502 experienced an average increase in time from penetration to ejaculation of 3.8 min, equating to a 6.3-fold increase in geometric mean IELT. The IELT in placebo-treated men increased to only 1.1 min, 1.7 times longer than baseline measurements.

Validated sexual quality of life questionnaires were completed by all patients and partners at baseline and at monthly clinical visits. These assessments revealed notably greater improvements in perceived control, personal distress, and satisfaction with sexual intercourse for patients and partners in the PSD502 group compared with those in the placebo group.

No serious adverse effects were reported. “It [PSD502] was well tolerated by both patients and their partners, with no systemic side effects and a low incidence of localized effects, and was rated favorably by the majority of users,” says Dinsmore.