PrEP recommended for MSM who seek postexposure prophylaxis

Around 2 percent of people seeking post-exposure prophylaxis (PEP) eventually test positive for HIV within 4 years, a recent study has found. This trend is particularly pronounced among men who have sex with men (MSM), strongly suggesting the potential for the early consideration of pre-exposure prophylaxis (PrEP) after a first episode of PEP.

Researchers retrospectively assessed data from 975 individuals who had sought PEP between 2007 and 2013. Privacy-preserving probabilistic linkage analysis was performed to connect the records to observational databases for HIV events.

After exclusions and combining records from internal and external linkages, a total of 22 HIV infections were detected, yielding a 2.3-percent incidence rate among people who had sought PEP. The median time from PEP to HIV diagnosis was 4.1 years.

Notably, all cases of HIV occurred in MSM. In comparison, MSM comprised only 34.4 percent of PEP-seekers who tested negative for HIV (p<0.0001). Among MSM who received PEP, 6.3 percent eventually got diagnosed with HIV.

Risk factor analysis found that those who tested positive for HIV were significantly more likely to have been indicated for PEP (81.8 percent vs 53.7 percent; p=0.009; odds ratio, 3.72, 95 percent CI, 1.37–12.99). However, the MSM variable proved to be too strong (ie, all HIV diagnoses were in MSM), such that meaningful multivariable analysis was impossible.

“Findings from our study may … contribute to closing the knowledge gap regarding the timing of PEP to PrEP transition in MSM. More specifically, a first, successful PEP episode (ie, completed without subsequent HIV infection) should trigger eligibility screening for PrEP,” the researchers said.