Pre-exposure prophylaxis (PrEP) is a highly effective tool that has the power to revolutionize the human immunodeficiency virus (HIV) prevention toolbox, with use rising among US men who have sex with men (MSM)[1–3]. Rapid, subsidized, PrEP implementation among key populations can dramatically reduce HIV incidence, even in populations with high HIV treatment coverage [2]. However, disparities remain, with less PrEP use among black MSM and youth, particularly in the Southeastern United States, populations with disproportionate HIV incidence [3]. Uptake is even lower among women and people who inject drugs [3]. The high adherence and retention in care seen in early PrEP demonstration projects [4] has not been sustained among later PrEP adopters within routine clinical settings, with 37–62% discontinuing PrEP by 6 months [5–7]. Higher rates of PrEP discontinuation among youth and black MSM, observed across multiple studies [4, 5], are likely to only amplify disparities in the HIV epidemic. PrEP persistence, or sustaining

PrEP use over time, has become a critical issue in PrEP implementation. Although PrEP starts can be readily measured by health departments and other agencies, it is more challenging to measure continued use, despite its importance to PrEP's impact, with limited data on PrEP persistence available [3]. Well-designed cohorts, with the ability to measure PrEP starts and stops through close contact with participants, are an important tool to understanding PrEP persistence. In this issue of Clinical Infectious Diseases, Serota and colleagues present data on PrEP uptake and discontinuation among young black MSM (YBMSM; aged 16–29 years) in the EleMENt longitudinal cohort, enrolled in Atlanta, Georgia. EleMENt was originally designed to examine the relationship between substance use and HIV/sexually transmitted infection (STI) incidence. YBMSM were recruited on the basis of reporting at least one male partner in the prior 3 months, with 298 enrolling in the study. Importantly, study recruitment was not predicated on PrEP interest, nor was there a requirement for high levels of behavioral risk. With the approval of PrEP in 2012, the study obtained PrEP supplemental funding for coverage of provider visits, laboratory testing, travel to clinic visits, and financial navigation to obtain PrEP coverage through available benefit programs. Almost all participants who elected to start PrEP received it free of charge, and all participants were offered