AimsHalf of young adults diagnosed with HIV in South Africa start antiretroviral therapy (ART). We developed and field tested a facilitator-guided peer support group called Yima Nkqo (“Standing Tall” in isiXhosa) to promote treatment initiation for young adults newly diagnosed with HIV in communities around Cape Town.MethodsFollowing an adapted version of the UK Medical Research Council’s framework for developing complex interventions, we 1) identified evidence on previous interventions to improve ART uptake in sub-Saharan Africa; 2) collected and analyzed qualitative data on the acceptability of our proposed intervention; 3) proposed a theoretical understanding of the process of behavior change; and 4) developed an intervention manual and feedback tools. During field-testing, participant feedback on intervention acceptability, and team feedback on consistency of content delivery and facilitation quality, were analyzed using an iterative, rapid-feedback evaluation approach. In-depth written and verbal summaries were shared in weekly team meetings. Team members interpreted feedback, identified areas for improvement, and proposed suggestions for intervention modifications.ResultsBased on our formative research, we developed three, 90-minute sessions with content including HIV and ART education, reflection on personal resources and strengths, practice disclosing one’s status, strategies to overcome stressors, and goal setting to start treatment. A lay facilitator was trained to deliver intervention content. Two field testing groups (five and four participants, respectively) completed the intervention. Participants highlighted that strengths of Yima Nkqo included peer support, motivation, and education about HIV and ART. Team feedback to the facilitator ensured optimal consistency of intervention content delivery.ConclusionsIteratively developed in collaboration with youth and healthcare providers, Yima Nkqo is a promising new intervention to improve treatment uptake among young adults with HIV in South Africa. The next phase will be a pilot randomized controlled trial of Yima Nkqo (ClinicalTrials.gov Identifier:NCT04568460).