The Characteristics of Men Who Have Sex With Men (MSM) Using Post-Exposure Prophylaxis for Sexual Exposure (PEPSE) in the Pre-Exposure Prophylaxis (PrEP) Era

Daniel Richardson; Kayleigh Nichols; Richard Hughes; Hannah Smith; Colin Fitzpatrick; Fiona Cresswell


HIV Medicine. 2022;23(5):553-557. 

In This Article

Abstract and Introduction


Objectives: HIV pre-exposure prophylaxis (PrEP) is now available in the UK. However, some men who have sex with men (MSM) continue to use HIV post-exposure prophylaxis following sexual exposure (PEPSE) and are not using PrEP. It is important to characterize MSM having condomless anal sex who are not using PrEP.

Methods: In a cross-sectional analysis, we compared the characteristics of MSM who used PEPSE in 2021 with MSM using PEPSE in 2017.

Results: Overall, 126 MSM used PEPSE in January to June 2017 and 28 MSM used PEPSE in January to June 2021, a 78% decline in PEPSE use. Those MSM using PEPSE in 2021 were significantly younger (27 vs. 35 years, p < 0.01), more likely to identify as black or from another minority ethnic group [29% (8/28) vs. 8% (10/126); p < 0.01], more likely to attend as a result of a group sex encounter [35% (10/28) vs. 16% (10/126); p = 0.03], more likely to attend following sex involving recreational drug use [32% (9/28) vs. 13% (16/126); p = 0.02], and more likely to initiate PEPSE in the emergency department [35% (10/28) vs. 19% (24/126); p = 0.04] compared with MSM attending in 2017. Those MSM using PEPSE in 2021 were significantly less likely to attend follow-up appointments compared with the 2017 cohort [71% (20/28) vs. 87% (110/126); p < 0.05]. Ninety-five per cent of MSM using PEPSE in 2021 were initiated on PrEP at follow-up.

Conclusions: Despite PrEP being readily available, some MSM continue using PEPSE and these MSM are significantly more likely to be younger, from black or minority ethnic groups, to engage in group sex involving recreational drugs and to attend the emergency department for PEPSE compared with MSM attending in 2017. Increasing the accessibility of PrEP for this group of MSM is important in order to optimize HIV prevention strategies.


HIV post-exposure prophylaxis following sexual exposure (PEPSE) is a 28-day course of antiretrovirals started as soon as possible following a potential sexual exposure to prevent HIV transmission.[1] Men who have sex with men (MSM) who use PEPSE have a 2.5- to 5-fold increase in HIV acquisition in the months after PEPSE, compared with MSM who do not need PEPSE.[2] HIV pre-exposure prophylaxis (PrEP) involves taking fixed-dose tenofovir/emtricitabine tablets either daily or event-driven and is highly effective at preventing HIV transmission, particularly in MSM.[3] Owing to the high risk of HIV seroconversion, it is recommended that HIV-negative MSM on PEPSE transition immediately to PrEP following the 28 days of PEPSE.[4,5]

Men who have sex with men can experience significant barriers to accessing healthcare, including HIV prevention strategies such as PrEP.[6,7] It is concerning that some MSM have no or poor access to PrEP, or are using PrEP inconsistently and continue to attend sexual health clinics or emergency departments for PEPSE.[8,9] Poor access to PrEP is associated with HIV transmission, particularly within marginalized populations of MSM, including those who identify as being from black and minority ethnic groups and those who use recreational drugs during sex.[8,9] Studies suggest that in areas with relatively good access to PrEP, marginalized populations of MSM either never attend clinical services for PrEP or are poorly adherent to PrEP, leading to HIV seroconversion. Since 2020, PrEP has been readily available to MSM in the UK, free of charge from sexual health clinics, furthermore STI testing and monitoring for PrEP is also free of charge for MSM in sexual health clinics. Locally we have introduced additional PrEP clinics including out-of-hours and the PrEP is dispensed directly from the clinic with no requirement to go to a pharmacy. However there are significant challenges in making PrEP accessible to marginalized populations of MSM who face barriers to accessing and adhering to PrEP.[8,9] To inform public health strategies aimed at increasing the access to PrEP for MSM, we need to identify those MSM who continue to attend for PEPSE who are not using PrEP. The aim of this study was to explore the characteristics of MSM who attend for PEPSE from a clinic based population in 2021 compared to MSM attending in 2017 when PrEP was not readily available in the UK.