Key population-led community-based same-day antiretroviral therapy (CB-SDART) initiation hub in Bangkok, Thailand: a protocol for a hybrid type 3 implementation trial.

Background: Same-day antiretroviral therapy (SDART) initiation, in which people living with HIV (PLHIV) who are antiretroviral therapy (ART)-naïve, willing, and clinically eligible start ART on the same day of HIV diagnosis, has been implemented in several healthcare facilities in Thailand since 2017. This evidence-based practice has demonstrated increased ART uptake, virologic suppression, and retention in care. However, linkage to care gaps exist in community-based organizations (CBOs) in Bangkok whereby as much as 20% of key populations (KP), mainly men who have sex with men and transgender women, living with HIV were lost to follow-up pre-ART initiation. To increase access to and uptake of ART among these populations, this study proposes that trained KP lay providers should lead community-based ART (CB-SDART) initiation service. This protocol describes the combined use of the Proctor's implementation outcome framework and the Consolidated Framework for Implementation Research to guide and evaluate the CB-SDART implementation.

Methods: This study follows the hybrid design type 3: it is an implementation trial that secondarily assesses service and client outcomes by comparative interrupted time series analysis. Five strategies have been formulated to meet three implementation outcomes (i.e., feasibility, fidelity, and sustainability): (1) developing stakeholder relationships by engaging the CBO leaderships, (2) training and educating KP lay providers, (3) adapting and tailoring SDART to CBO-specific context, (4) using evaluative and iterative strategies to assess adherence to standard operating procedures, and (5) developing stakeholder relationships by engaging external stakeholders. Teleconsultation with physicians and ART home delivery will be integrated as another ART initiation option for clients and allow service provision during the COVID-19 pandemic. A mixed-method assessment will be conducted on key stakeholders and PLHIV diagnosed at two implementing CBOs, Rainbow Sky Association of Thailand and Service Workers in Group Foundation, in Bangkok, Thailand.

Discussion: This implementation research may be the first to provide robust data at the implementation, service, and client levels to inform how to successfully task-shift SDART initiation service to trained KP lay providers and facilitate the expansion of CB-SDART in the future.

Trial Registration: This trial was registered with the Thai Clinical Trial Registry as TCTR20210709004 on July 9, 2021.