Pre-exposure prophylaxis (PrEP) for HIV prevention is highly effective, but uptake remains low among young women in sub-Saharan Africa, one of the populations at greatest HIV risk. In Kenya, one of the target groups for HIV incidence reduction is young women (16-24 years), who account for 33% of the total of new HIV infections, yet comprise only 10% of the population. Barriers to PrEP initiation for this population are multi-faceted and include institutional (e.g., stigma associated with use) and intra-personal (e.g., lack of PrEP knowledge or self-efficacy) barriers. Thus, innovative PrEP delivery models that can help overcome these barriers are needed. The opinion of peers often influences the behaviors and preferences of young women, including those related to health and health care. Most young women who have initiated PrEP in Kenya to date have done so because of peer referral, thus formalized and enhanced peer referral has the potential to increase PrEP initiation among members of this population. HIV self-testing (HIVST) is a new technology that has the potential to enhance peer PrEP referral. Much of the emphasis on HIVST to date has been on identifying new individuals living with HIV and facilitating linkage to treatment, but the majority of individuals who self-test will test negative and may be interested in facilitated linkage to prevention services, like PrEP.

We hypothesize that a formalized peer PrEP referral + HIVST delivery model can amplify PrEP initiation among young Kenyan women at HIV risk. We conducted formative qualitative research and stakeholder engagement to develop a model of formalized peer PrEP referral + HIVST delivery to increase PrEP initiation among young Kenyan women. We propose refining this model in a pilot study. In our pilot, we will recruit 16 young female PrEP users (i.e. peer providers) in Thika, Kenya to deliver the formalized peer PrEP referral + HIVST model to \~4 peers (i.e., peer clients, =64 peer clients in total). At one month, we will quantitatively measure model adoption (e.g., peer referral, PrEP initiation) and feasibility (e.g., peer follow up) using surveys, and qualitatively measure acceptability using focus group discussions (FDGs) with those delivering and receiving the model (4-5 FDGs, 3-6 women/FDG).

We then propose testing the refined model in hybrid effectiveness-implementation trial. In our trial, we will randomize 80 peer providers to: 1) "formal peer PrEP referral + HIVST delivery", where they are encouraged to refer 4 peer clients to PrEP using an educational brochure, HIVSTs (2/peer, =8 total), and a MOH-style referral slip, vs. 2) "informal peer PrEP referral", where they are encouraged to refer 4 peer clients to PrEP using word-of-mouth, as is ongoing in Kenya, and a MOH-style referral slip. All trial outcomes will be measured among peer clients, as reported by peer providers, three months later. Implementation outcomes will include acceptability, fidelity, and costs. The effectiveness outcomes will be PrEP initiation \[primary\], PrEP continuation (i.e., refilling), recent HIV testing use (past 3 months), and PrEP adherence, confirmed using dried blood spots. The results from this trial will address one of the greatest challenges to PrEP scale-up today and inform an R01 proposal for a community-randomized trial and budget impact analysis.