New HIV infections occur at a disproportionately high rate among young men who have sex with men (YMSM).Oral pre-exposure prophylaxis (PrEP) can reduce HIV acquisition among MSM over 90% when adherence levels are high, and increasing the effective use of PrEP among YMSM is one of the highest priorities in HIV prevention. However, YMSM face multiple barriers to initiating and adhering to PrEP, including structural barriers (e.g. housing insecurity), psychosocial factors (e.g. substance use, depression), underestimation of their risk for acquiring HIV, and ambivalence about using PrEP due to medical mistrust. In an open-label study of PrEP use by 200 YMSM, only one-third of participants had protective levels of drug in their blood at 1 year despite intensive adherence counseling, and HIV incidence was high at 3% per year. When PrEP is prescribed to YMSM in care settings, where adherence support is less intensive than in clinical studies, adherence levels, and thus effectiveness, are likely to be even lower. Without strategies to optimize adherence to PrEP for these youth, PrEP is unlikely to have a major impact on HIV incidence for YMSM.

One approach to overcoming the multi-factorial barriers that prevent YMSM from adhering to PrEP is the use of peer health system navigators. Navigators are healthcare workers who are trained to support adherence and retention in care for individuals who are at risk for suboptimal adherence. For YMSM who use PrEP, peer navigators could support adherence by connecting youth with resources to address their unmet structural and psychosocial needs and by helping them to negotiate the complexities of healthcare systems. An NICHD-funded study conducted in Boston (SMILE: Strategic Multisite Initiative for the Identification, Linkage and Engagement in Care of Youth with Undiagnosed HIV) found that peer navigation was highly acceptable for newly diagnosed HIV-infected youth, so it is likely that YMSM will find peer navigation to be acceptable for PrEP. As navigators have been used for over a decade to improve adherence in HIV-infected persons, and an evaluation showed that HIV-infected persons who used navigators had higher rates of virologic suppression, it is important to test whether peer navigation can optimize adherence to PrEP for YMSM.

Our long-term goal is to optimize adherence to PrEP for YMSM and thus decrease HIV incidence. The objective of this study, the first step towards our goal, is to develop and pilot test a peer navigator program to optimize adherence to PrEP for YMSM. We will recruit at-risk YMSM from an LGBTQ Youth-focused community health center with PrEP expertise, the Sidney Borum Jr. Health Center. The Borum Center provides care to 1200 YMSM aged 12-29 annually, half of whom are Black or Latino and 20% of whom are homeless. As incidence rates for HIV (2%) and syphilis (9%) in 2015 were over 20 and 100-fold higher at this center than in the general Boston population, and its clinicians initiate PrEP for 3-4 YMSM monthly, the Borum Center is an ideal setting to explore adherence to PrEP among the highest risk YMSM. Our specific aims are:

Aim 1. To explore perceived facilitators and barriers to initiating and adhering to PrEP among at-risk YMSM. We will conduct in-depth qualitative interviews with 32 YMSM at the Borum Center, including 8 youth who have not yet discussed PrEP with clinicians, 8 who have declined PrEP when offered by clinicians, 8 who have been adherent to PrEP, and 8 with suboptimal adherence. Discussions will include in-depth exploration of YMSM attitudes and intentions regarding PrEP and PrEP peer navigators. We will use purposive sampling to recruit a diverse sample with respect to race, ethnicity, and age, including youth who are minors.

Aim 2. To assess the acceptability and feasibility of a culturally-tailored peer navigator program to optimize adherence to PrEP among YMSM. A PrEP peer navigator program will be adapted from the SMILE study and will be informed by our findings from Aim 1. We will pilot test the program for acceptability and feasibility with 15 YMSM who are newly initiating PrEP at the Borum Center. Secondary outcomes include retention in PrEP care and adherence to PrEP, as measured by dried blood spot testing, at 3 and 6 months.