HIV Pre-Exposure Prophylaxis Does Not Increase Risky Sexual Behaviors: A Study in West Africa

In west Africa, increased availability of HIV pre-exposure prophylaxis (PrEP) was not found to increase risky sexual behaviors or bacterial sexually transmitted infections (STIs) among men who have sex with men (MSM). These findings, from a prospective cohort study, were published in Lancet HIV.

Between 2017 and 2020, MSM were recruited at 4 centers in Côte d’Ivoire, Mali, Togo, and Burkina Faso for the CohMSM-PrEP study, which was an extension of the 2015 CohMSM trial. Participants (N=598) could choose between one daily dose of PrEP (tenofovir disoproxil fumarate 300 mg and emtricitabine 200 mg) or an event-driven drug course (2 tablets taken 2 to 24 hours before a sex act and 1 tablet every 24 hours afterward for 2 days). Visits with physicians and peer educators occurred at 0, 1, and 3 months and every 3 months thereafter for HIV and STI screening.

Participants were from Mali (41%), Côte d’Ivoire (20%), Togo (20%), or Burkina Faso (20%).  Median age was 24.6 years (interquartile range [IQR], 21.9-27.9), 58% were self-defined as bisexual, 60% were self-identified as a man or boy, 44% reported systematic condom use, 81% had previously been screened for HIV, and 7% had symptoms of a non-HIV STI.

The median follow-up time was 17.6 months (IQR, 7.3-21.8). Most participants chose to use event-driven PrEP (74%) over daily PrEP (26%), and 21% switched dosing regimen during the study.

HIV seropositivity was observed among 17 participants at a median of 11.5 months, corresponding with an event rate of 2.3 (95% CI, 1.3-3.7) per 100 person-years. Review of the data collected before the distribution of PrEP (CohMSM trial) revealed an HIV incidence rate of 10.0 (95% CI, 8.0-12.5) per 100 person-years. PrEP was associated with decreased HIV seropositivity (adjusted incidence rate ratio [aIRR], 0.21; 95% CI, 0.12-0.36).

Among newly HIV-positive individuals, 15 used event-driven PrEP, 1 used daily PrEP, and 1 had discontinued use. HIV seropositivity occurred at a rate of 2.7 per 100 person-years for event-driven, 0.6 per 100 person-years for daily, and 6.1 per 100 person-years for no PrEP use.

Optimal adherence was poorer among those using event-driven PrEP vs the daily regimen (adjusted odds ratio [aOR], 0.20; 95% CI, 0.11-0.38; P <.0001). More participants using daily PrEP reported using both prophylaxis and condoms (P =.013). Condom use alone was unchanged (P =.71).

The average number of sexual partners decreased during the study (P <.0001), more so among the event-driven PrEP cohort (P =.019). The number of sex acts also decreased for those engaging in 1 to 4 (P =.0014) and at least 5 (P =.030) acts.

At baseline and month 12, the incidence of gonorrhea (12.6% vs 14.0%), chlamydia (19.3% vs 20.0%), and syphilis (0.2% vs 1.0%) remained relatively stable.

This study may not be generalizable to populations outside of major cities, as the study communities tended to be more open and accepting of MSM populations.

This study found no evidence of increased incidence of risky sexual behaviors associated with the use of HIV PrEP among MSM in west Africa.  The investigators advise that PrEP should be urgently dispensed to these communities at high risk of HIV.

Reference

Laurent C, Keita BD, Yaya I, et al. HIV pre-exposure prophylaxis for men who have sex with men in west Africa: a multicountry demonstration study. Lancet HIV. 2021;S2352-3018(21)00005-9. doi:10.1016/S2352-3018(21)00005-9