female sexual arousal disorder (FSAD)

Symptoms of female sexual arousal disorder (FSAD) improved significantly during treatment with a topical prostaglandin compared with placebo, results of a randomized clinical trial showed.

Women who used alprostadil (Femprox) cream had as much as 63 percent improvement in the primary outcome of satisfactory sexual encounters, as defined by responses to a validated sexuality questionnaire.

Women who used the highest concentration of alprostadil cream had significant improvement in all primary and secondary endpoints compared with placebo, as reported here at the American Urological Association meeting.

"I think these results are exciting," Irwin Goldstein, MD, of San Diego Sexual Medicine in California, told MedPage. "Women have sexual problems, and we really haven't been addressing them. We haven't been giving them choices, like men have choices, and women need choices just like men do."

Topical alprostadil was generally well tolerated, and adverse events were consistent with drug's known effects, he added.

Some women may find certain nonprescription products helpful with minor problems related to sexual arousal. However, more severe forms of FSAD have proven unresponsive to multiple therapies, including phosphodiesterase type 5 inhibitors and, most recently, topical testosterone preparations.

Alprostadil (Muse) has demonstrated efficacy in the treatment of erectile dysfunction in men. An injectable formulation is approved in the U.S. and a topical formulation has approval in Canada. The topical formulation's vehicle contains a proprietary skin-penetration enhancer that temporarily relaxes tight skin junctions to enable alprostadil delivery and penetration.

Effective tissue penetration by alprostadil results in vasodilation, smooth muscle relaxation, and increased blood flow. Men apply the cream to the head of the penis, whereas the higher dose developed for women is applied to the clitoris and distal anterior vaginal wall, considered the G spot.

"Everyone understands that when you have desire it leads to sexual activity, which is followed by blood flow to the genital tissue, causing an arousal and engorgement response," Goldstein said. "If a woman has issues with arousal, it's problematic. We understand that. That's what erectile dysfunction is in men. There's absolutely no reason not to think that there is a subgroup of women who are unhappy with their sex lives and who could improve their sex lives if they had an appropriate topical agent that's a little stronger than what is currently available."

Overall, 33 percent of women allocated to placebo had improvement in satisfactory sexual encounters, compared with 46.3 percent, 43.5 percent, and 53.9 percent of women in the alprostadil groups.

The study population consisted of 168 women ages 21 to 45 and 206 women ages 46 to 65, for a total of 374 in an intent-to-treat analysis. Evaluation of the primary endpoint by age group showed that 33 percent of placebo-treated patients had improvement regardless of age.

Age-stratified response rates differed across the alprostadil dose groups, but a higher proportion of women in each group had improvement compared with placebo. In the 500-µg arm, 49 percent of older women and 42 percent of younger women improved. In the 700-µg arm, 46 percent of younger women and 41 percent of older women improved.

The highest response rate occurred among younger women randomized to 900 µg of alprostadil, as they reported that 61 percent of sexual encounters were satisfactory. Older women had a 47 percent response rate.

With respect to secondary endpoints, younger women randomized to the highest concentration of topical alprostadil derived the greatest benefit versus placebo.