Daily and event‐driven pre‐exposure prophylaxis for men who have sex with men in Belgium: results of a prospective cohort measuring adherence, sexual behaviour and STI incidence

Abstract

Introduction Pre‐Exposure Prophylaxis (PrEP) is highly effective in reducing the risk for HIV infection among men who have sex with men (MSM) and may have an important impact in slowing down the HIV epidemic. Concerns remain however about low adherence, increased risk behaviour and reduced condom use when using PrEP. The aim of this study was to assess these factors prospectively among MSM using daily and event‐driven PrEP in Belgium. Methods An open‐label prospective cohort study was conducted from October 2017 to May 2018 at the Institute of Tropical Medicine, in Antwerp, Belgium. At enrolment, MSM at high risk for HIV chose between daily or event‐driven PrEP. They were allowed to switch regimens or stop taking PrEP at each of their tri‐monthly visits. Data were collected on an electronic case report form, web‐based diary and self‐administered questionnaire. Screening for HIV and other Sexually Transmitted Infections (STIs) was also performed. Results Two hundred MSM were followed up for a total duration of 318 person‐years. At month 18, 75.4% of the participants were on daily and 24.6% were on event‐driven PrEP. The mean proportion of covered sex acts by PrEP for the complete follow‐up period was 91.5% for all participants, 96.5% for daily and 67.0% for event‐driven PrEP use. The number of casual and anonymous sex partners was significantly higher for daily users, as compared with event‐driven users, but did not change over time. In contrast, the mean proportion of condomless receptive anal intercourse with casual and anonymous partners increased significantly during follow‐up, for both daily and event‐driven use (p < 0.0001 for all 4 trends). No new HIV infection was diagnosed during follow‐up. The incidence of bacterial STIs was 75.4 per 100 person‐years (95% CI 63.8 to 89.1). We did not detect a significant change in N. gonorrhoeae/C. trachomatis incidence over time. The incidence of hepatitis C was 2.9 per 100 person‐years. Conclusions PrEP is an effective and well adopted HIV prevention tool for MSM in Belgium. Participants adapted daily and event‐driven regimens to their own needs and were able to adapt their PrEP adherence to risk exposure.

Understanding pre-exposure prophylaxis (PrEP) regimen use: Switching and discontinuing daily and event-driven PrEP among men who have sex with men

“…Nevertheless, overall discontinuation rates in our study were comparatively low: other demonstration projects found similar rates over much shorter follow-up time [ 20 , 27 , 28 ] and higher discontinuation rates were observed in larger-scale clinical or primary care implementation settings [ 13 , 29 ]. As our project is one of the few offering a choice of PrEP regimens, PrEP discontinuation might be low when having access to an alternative, non-daily regimen.…”

Preference for daily versus on‐demand pre‐exposure prophylaxis for HIV and correlates among men who have sex with men: the China Real‐world Oral PrEP Demonstration study

“…Depending on how often it is taken, on-demand PrEP could use far fewer than half the number of pills for a daily regimen over a month. Recent studies in Belgium and Netherlands found that 19% to 30% of PrEP users switched their regimen during follow-up [5,31], suggesting that switching regimen is relatively common and that daily and on-demand PrEP regimens are fluid [31]. Instead of making daily and on-demand PrEP into two different regimens, it is more reasonable to tailor PrEP use basing on one's current risk or create a new "combined" dosing regimen.…”

Barriers to using HIV pre-exposure prophylaxis (PrEP) and sexual behaviour after stopping PrEP: a cross-sectional study in Germany

“…Not wanting to take a daily pill was indicated by 23.3% of the participants as a reason for stopping PrEP. While the current guidelines in Germany endorse only daily PrEP use, other studies have found that PrEP also has a positive efficacy and safety profile when taken ‘on demand’ [ 12 , 38 ]. It would be interesting to investigate whether on-demand PrEP may be a suitable option for people who are unwilling to take a daily pill.…”