PROJECT SUMMARY/ABSTRACT In the United States, HIV and sexually transmitted infections (STIs) disproportionately affect adolescents and young adults (AYA). Youth aged 13-­24 years comprise ~21% of incident HIV cases. In addition, 2017 data demonstrated the fourth consecutive year of increasing STI rates, with the highest incidence occurring in AYA. Amidst these public health challenges, the 2018 licensure of tenofovir-­emtricitabine as HIV pre-­exposure prophylaxis (PrEP) for adolescents presents a key opportunity for enhancing youth HIV and STI prevention services. Currently, <2% of U.S. PrEP prescriptions are for adolescents <18 years of age. Pediatric primary care providers (PCPs) are thus well-­positioned to expand PrEP delivery. However, sexual health service delivery in primary care is hampered by PCP time constraints and competing demands. There is a critical need for both behavioral interventions to increase PrEP uptake and reduce STIs in adolescents, and implementation strategies to disseminate PrEP and enhanced sexual health services in adolescent primary care. The goal of this K23 application is to facilitate Dr. Sarah M. Wood’s long-­term goal of becoming an independent investigator in adolescent HIV and STI prevention through an integrated program of training and applied research that will prepare her to meet the challenges of the current HIV and STI epidemics. This award will also focus on her short-­term goal of gaining the methodologic expertise needed to adapt, optimize for implementation, and test, a developmentally-­tailored, PrEP-­inclusive, HIV/STI prevention health coaching intervention for adolescents in primary care. The training objectives focus on content areas where she currently lacks the methodologic expertise to carry out this goal: 1) bio-­behavioral intervention adaptation, 2) implementation science, and 3) clinical trial methodology. This training plan will be bolstered by a highly skilled mentorship team with expertise in intervention development, adolescent sexual health and qualitative methodology, and primary care pragmatic clinical trials. The advisory team will provide further expertise in developmental tailoring, prevention science, implementation science, mental health measurement and targets, and clinical trial design and analysis. Dr. Wood’s training objectives will progress in parallel with, and inform, her applied research aims. Aim 1 will use qualitative methods and the ADAPT-­ITT framework to adapt the health coaching intervention. Aim 2 will determine acceptability and feasibility of the intervention among primary care providers, and develop an optimized primary care implementation strategy for the intervention. Finally, Aim 3 will conduct a small randomized controlled trial to test the intervention for change in prevention self-­efficacy, as well as acceptability and feasibility and in adolescents with a history of STI. The culmination of Dr. Wood’s research and training will be the submission of a R01 application for a type I hybrid randomized effectiveness-­implementation trial of the health coaching intervention.

PROJECT NARRATIVE In the U.S., youth ages 15-24 years comprise only 13% of the U.S. population, but represent 21% of incident HIV and approximately 50% of incident STI cases, underscoring the critical need for innovative research to address these co-occurring epidemics. Conducting the proposed research within the structure of a mentored, career development framework, with focused training in behavioral intervention adaptation and development, implementation science, and clinical and pragmatic trial design and management will help establish my career as an independent clinician-scientist dedicated to HIV and STI prevention in adolescents and young adults. The program of applied research and associated training delineated in this award will focus on the adaptation (Aim 1), implementation optimization (Aim 2), and testing (Aim 3) of a PrEP-inclusive health coaching intervention to reduce HIV and STI incidence among adolescents and young adults, which aims to be scalable across primary care contexts.