PositiveLinks for Youth (PL4Y) for Texas: Effectiveness, feasibility, and acceptability of mHealth to improve care outcomes for young adults with HIV - PL4Y for Texas – Project Summary Emerging adults and youth living with HIV 18-29yo (YWH) are the least likely of any age group to engage in care or achieve virologic suppression, and Southern YWH live at the epicenter of the modern U.S. HIV epidemic. In Texas, molecular clusters of rapid HIV transmission among youth highlight missed opportunities including delays in care engagement and virologic suppression. We demonstrated that an mHealth intervention, PositiveLinks for Youth (PL4Y), developed in collaboration with YWH in South Texas (R34 MH122332) showed high acceptability and feasibility and was associated with increased virologic suppression from 44% in the control group to 80% in the intervention group in a pilot randomized control trial. Our long-term goal is to improve rates of virologic suppression for YWH, which transforms HIV from deadly to a chronic illness, and ensures YWH live long and healthy lives. mHealth interventions, such as smartphone applications (apps), are rapidly adopted by youth, and are an underutilized resource in increasing care engagement for YLWH. This project proposes to implement and rigorously test PL4Y in a six-clinic network in Texas that builds upon existing strong collaborations and represents four of the five Ending the HIV Epidemic (EHE) priority jurisdictions in Texas: Austin, Dallas, Houston and San Antonio. PL4Y is a multimodal intervention, including daily adherence and mood assessment, appointment reminders, secure messaging, and an anonymous, asynchronous virtual support group. We assembled a highly qualified team of clinician researchers, implementation scientists, and behavioral intervention experts to build upon our existing body of work to expand PL4Y. We will also sustain and expand our robust PL4Y Youth Advisory Board (YAB) to provide input throughout the process. Our central hypothesis is that PL4Y implementation will lead to increased viral suppression among YWH across Texas. To test this hypothesis, we will first prepare for geographic expansion of PL4Y across Texas (Aim 1). This will involve brainstorming sessions in each of the six participating clinics to identify facilitators and barriers to PL4Y implementation. We will then conduct process meetings with a medical provider champion and other clinic stakeholders to prepare for the implementation of PL4Y. Next, in Aim 2, we will conduct a cluster randomized longitudinal staircase trial in 6 clinics, following 600 YWH, 100 per clinic, across Texas for 12 months. The primary outcome will be virologic suppression (viral load <200 copies/mL) at 12 months. Finally, we will assess the acceptability, feasibility, and sustainment opportunities for the PL4Y intervention. Our findings can be used to support improved health outcomes for YWH in other settings and for youth with other chronic medical conditions. Every year, the HIV epidemic expands among youth in the U.S. South, jeopardizing our EHE goals. Youth-specific, effective tools, like PL4Y, are urgently needed to address this growing challenge.