BackgroundAntiretroviral therapy (ART) through universal test and treat (UTT) and HIV pre-exposure prophylaxis (PrEP) substantially reduces HIV-related mortality, morbidity and incidence. Effective individual-level prevention modalities have not translated into population-level impact in southern Africa due to sub-optimal coverage among adolescents and youth who are hard to engage. We aim to investigate the feasibility, acceptability, and preliminary population level effectiveness of HIV prevention services with or without peer support to reduce prevalence of transmissible HIV amongst adolescents and young adults in KwaZulu-Natal.MethodsWe are conducting a 2 × 2 factorial trial among young men and women aged 16–29 years, randomly selected from the Africa Health Research Institute demographic surveillance area. Participants are randomly allocated to one of four intervention combinations: 1) Standard of Care (SOC): nurse-led services for HIV testing plus ART if positive or PrEP for those eligible and negative; 2) Sexual and Reproductive Health (SRH): Baseline self-collected vaginal and urine samples with study-organized clinic appointments for results, treatment and delivery of HIV testing, ART and PrEP integrated with SRH services; 3) Peer-support: Study referral of participants to a peer navigator to assess their health, social and educational needs and provide risk-informed HIV prevention, including facilitating clinic attendance; or 4) SRH + peer-support.The primary outcomes for effectiveness are: (1) the proportion of individuals with infectious HIV at 12 months and (2) uptake of risk-informed comprehensive HIV prevention services within 60 days of enrolment. At 12 months, all participants will be contacted at home and the study team will collect a dried blood spot for HIV ELISA and HIV viral load testing.DiscussionThis trial will enable us to understand the relative importance of SRH and peer support in creating demand for effective and risk informed biomedical HIV prevention and preliminary data on their effectiveness on reducing the prevalence of transmissible HIV amongst all adolescents and youth.Trial registrationTrial Registry: clincialtrials.gov. ClinicalTrials.gov Identifier NCT04532307. Registered: March 2020.