Acceptability of an "on-demand" pre-exposure HIV prophylaxis trial among men who have sex with men living in France.

Although predictors of willingness to take daily, self-administered pre-exposure HIV prophylaxis (PrEP) for men who have sex with men (MSM) have been studied in the context of several PrEP trials internationally, little is known about MSM interested in participating in a trial on the use of PrEP on an "on -demand" basis, i.e., taking a first dose of combined tenofovir/emtricitabine a few hours before possible HIV sexual exposure and a second dose a few hours afterwards. A double-blind placebo randomized PrEP trial will soon begin in France to evaluate the effectiveness of PrEP in terms of reducing HIV infection rates, among MSM self-administering "on-demand" PrEP. To assess potential participants' characteristics associated with willingness to participate in the trial and identify barriers and facilitators to implementation, MSM completed a self-administered questionnaire, distributed via gay venues and community websites. Among the 443 respondents who reported being HIV-negative, 40% reported being interested in participating. Factors independently associated with interest included: reporting lower educational level, more than 20 male sexual partners in the previous year, reporting unprotected anal sex with casual partners and preferring PrEP follow-up visits in a devoted area within a hospital. There is great interest in participating in a future "on-demand" PrEP trial among HIV-negative MSM and particularly in those at potentially high risk of HIV exposure. Providing confidentiality and tailored counseling during PrEP follow-up are important issues.