Sexually transmitted infection testing and prevalence among MSM using event-based dosing HIV pre-exposure prophylaxis.

Event-based dosing (EBD) of HIV PrEP is as effective at preventing HIV transmission in MSM as daily dosing. There are limited data on the differences in STI testing frequency between MSM using EBD-PrEP and daily dosing. A total of 20% of 418 PrEP users were using EBD-PrEP and had a lower number of sexual partners (22 (27%) vs 142 (42%), P =0.008), tested for STIs less frequently (115 (18%) vs 69 (50%), P <0.001), but were diagnosed with a similar number of STIs ((35% vs 34%, P =0.54) compared to daily users. More research is needed to understand the optimal frequency for STI testing in MSM using EBD PrEP.