The first U.S. trials of a spray-on anesthetic for the penis showed that it increased the time to ejaculation nearly five-fold, providing the first good solution for premature ejaculation, researchers reported today. The findings are very similar to those obtained in a European study released in April.
Premature ejaculation is generally defined as ejaculation that occurs within a minute after insertion of the penis into the vagina, causing distress to both parties. The condition is thought to affect as many as one in three U.S. men ages 18 to 59, about twice as many as those who suffer from erectile dysfunction. Some antidepressant-like drugs, such as dapoxetine, have been approved in a few countries to treat the condition, but the Food and Drug Administration rejected it because of long-term side effects. Some physicians prescribe anesthetic creams like EMLA cream for off-label use to delay ejaculation, but such creams require 45 minutes to work and the man must use a condom to prevent the anesthetic from numbing the woman.
Plethora Solutions of London and Sciele Pharma Inc. of Atlanta have developed a spray anesthetic, called PSD502 or Tempe, that contains lidocaine and prilocaine dispensed by a metered aerosol. It is applied five minutes before intercourse, and it selectively numbs the head of the penis.
The new trial, led by Dr. Michael G. Wyllie of Plethora enrolled 256 patients at 38 centers in the U.S., Canada and Poland. Their average duration of intercourse was less than 0.6 minutes. Two-thirds of the participants used PSD502; the rest were given a placebo. Wyllie reported today at a San Diego meeting of the Sexual Medicine Society of North America that men receiving the drug increased their intercourse time to an average of 2.6 minutes, compared with an increase to only 0.8 minutes in the placebo group. The benefits persisted for the three months of the study and both men and women reported greater satisfaction with their sexual experiences. No significant adverse effects were observed.
The company expects to apply for FDA approval of the drug in the first quarter of 2010, Sciele Chief Executive Patrick Forteau said.
-- Thomas H. Maugh II