Previously, cohort data from two studies found that behavioral- and sexually transmitted infection–based PrEP indication criteria, such as the CDC guidelines, perform poorly in predicting incident HIV infection among Black men who have sex with men (MSM).[3,4] In fact, one of the cohort studies found that race alone better predicted HIV incidence than did any of the risk screening tools, supporting the concept that sexual networks confer risk more than does individual behavior. This aligns with a meta-analysis that found risk behavior of Black MSM to be lower than risk behavior of White MSM, in stark contrast to HIV incidence, which is substantially higher among Black MSM than White MSM.
When this previous evidence is considered, PrEP screening tools predominantly composed of risk behavior data seem destined to perform poorly for Black MSM. The work of Pyra et al. provides clinic-level data supporting this conclusion. The implications are potentially enormous: clinicians strictly following CDC guidelines will exclude or deemphasize PrEP for a number of Black and Latinx persons who are at high risk of acquiring HIV, unintentionally increasing racial/ethnic disparities in HIV incidence. This also leads to a potential inefficient allocation of resources: organizations funded by CDC to conduct PrEP outreach to highly affected populations such as Black MSM may then proceed to not recommend PrEP to members of populations that are excellent candidates but lack a guidelines-based indication.
Some have suggested using abbreviated PrEP behavioral guidelines to facilitate clinical use, demonstrating that such criteria performed well for members of the iPrEx study (the Preexposure Prophylaxis Initiative trial). Yet, as the authors of that study acknowledge, such indications would likely perform poorly for Black MSM. Alternatives include individually tailored indications based on machine-learning models. This approach has the advantage of a high ability to predict incident infection that could alleviate disparities in indication but also the disadvantage of feasibility of scale-up and complexity of patient communication. Another possible approach would be to consider prescribing PrEP for all members of high-prevalence or high-incidence groups. Additional thought would be needed on potential cut points and how to approach other groups with greater heterogeneity of outcomes.
Am J Public Health. 2020;110(3):267-268. © 2020 American Public Health Association