Home-Based Community Health Worker Support for Mental Health among People Living with HIV: A Hybrid Effectiveness Implementation Trial - PROJECT SUMMARY. South Africa (SA) is home to the largest number globally of people with HIV (PWH). Mental health (MH) conditions, particularly depression and harmful alcohol use, are non-communicable diseases contributing greatly to HIV morbidity and mortality in SA due to poorer quality of life, lower engagement in HIV care, and worse disease progression. A key priority of SA Department of Health is to integrate MH services into an existing infrastructure of community health workers (CHWs) conducting home visits to engage PWH who are initiating or re-initiating HIV treatment. CHWs often encounter patients with MH, yet receive little MH training despite interest. Training CHWs in an evidence-based intervention to support PWH with MH concerns is a unique opportunity to improve HIV and MH outcomes. Guided by the ADAPT-ITT model for intervention adaptation and the Consolidated Framework for Implementation Research (CFIR), this proposal builds upon our prior work that developed clinic-based interventions for PWH to support MH and HIV care outcomes based on motivational interviewing, problem solving, and behavioral activation, and aims to adapt the approach and implementation strategies for home-delivery (“Khanya-Ekhaya”). We are leveraging a robust, existing infrastructure of CHWs doing home visits with PWH, thus promoting the sustainability of the proposed model. We propose to: (1) Explore multi-level barriers and facilitators to implementing a home-based CHW intervention (Khanya-Ekhaya) for PWH with MH concerns seen by a CHW after newly initiating or re-initiating ART. Guided by CFIR, we will conduct individual semi-structured interviews with CHWs (n=10), patients (n=30) and other key stakeholders (i.e., supervisors, policymakers, organizational leaders; n=10) to inform the adaptation and implementation strategy of Khanya-Ekhaya for home-based delivery for PWH with MH problems (depression/harmful alcohol use); (2) Adapt Khanya-Ekhaya for home-based, CHW delivery to improve HIV care engagement and MH symptoms based on Aim 1, guided by the ADAPT-ITT model and human-centered design principles. We will conduct four workshops with PWH with depression and/or harmful alcohol use (n=12) and CHWs (n=12) to identify adaptations to improve acceptability; (3) Evaluate the implementation and preliminary effectiveness of the home-based Khanya-Ekhaya CHW intervention in a pilot Type 1 hybrid effectiveness-implementation trial (n=20 CHWs), evaluating implementation outcomes (feasibility, acceptability, fidelity), and preliminary effects on HIV care engagement and MH symptoms (depression, harmful alcohol use). Implementation outcomes will be assessed among CHWs (n=10) and patients (n=25) using mixed methods. This proposal is responsive to PAR-23-191 as an innovative implementation science trial to support MH services shifting from clinic- to community-based care. Capacity building efforts will build a research network focused on MH and HIV clinical research in sub-Saharan Africa. Findings will inform an R01 to evaluate effectiveness and implementation of the CHW Khanya-Ekhaya intervention to reduce MH problems and improve HIV care engagement for PWH with MH concerns.