A phase 2b trial has evaluated the efficacy of topical sildenafil cream 3.6% for female sexual arousal disorder in premenopausal women.
The study—results of which were published in Obstetrics & Gynecology—randomized 200 women with female sexual arousal disorder (FSAD) at 49 U.S. sites to use sildenafil cream or placebo cream for 12 weeks, following a 28-day no-drug run-in period and a 28-day single-blind placebo run-in period. The trial included both partnered and unpartnered women, although the initial requirement for partner consent was a barrier to enrollment and was later amended. Participants applied 2 g of cream (1 g externally, 1 g internally) 10 to 20 minutes before sexual activity, with a maximum of nine applications per month. Of 833 volunteers screened, 200 were randomized, and 174 women (90 who used sildenafil, 84 who used placebo) completed all study visits. Baseline characteristics were similar between groups, with a mean age of 36.3 years and most participants being White and college-educated.
The coprimary efficacy endpoints of the study were change from baseline in the Sexual Function Questionnaire (SFQ28) Arousal Sensation domain and question 14 of the Female Sexual Distress Scale-Desire, Arousal, Orgasm (FSDS-DAO).
In the intention-to-treat population (n=193), sildenafil cream did not show statistically significant improvements over placebo in the coprimary endpoints at week 12. However, in a post hoc analysis of a subset of 65 women with FSAD only or FSAD with concomitant decreased desire (excluding those with orgasmic dysfunction or genital pain), sildenafil cream users experienced significant increases in the SFQ28 Arousal Sensation domain (2.03 vs 0.08, P=.04) and improvements in the SFQ28 Desire domain (1.27 vs -0.89, P=.06) and Orgasm domain (1.12 vs 0.18, P=.19) compared to placebo users at week 12. This subset also showed significant reductions in sexual distress on several FSDS-DAO items related to guilt, stress, and embarrassment about sexual difficulties (all P≤.04). The total FSDS-DAO score decreased by 7.06 points for sildenafil users vs 2.05 for placebo users (P=.10) in this subset.
The original sample size calculations aimed for 300 to 440 completers, but the study halted recruitment earlier due to slower-than-anticipated enrollment, partly attributed to the COVID-19 pandemic. Limitations included the homogeneous study population and post-hoc nature of the subset analyses.
The researchers noted that future studies may focus on women with FSAD alone or FSAD with concomitant decreased desire.
Conflict of interest disclosures were not made available at time of publishing.