The Siyaphambili Substance Use Study: Exploring Substance Use and Its Treatment in the Context of Achieving Sustained ART Adherence among Female Sex Workers
Funded by: National Institute on Drug Abuse
Project dates: September 2023 - August 2025
Principal Investigator: Knox, Justin
Principal Investigator: Schwartz SR (contact PI)

This study aims to increase understanding of substance use, how it impacts HIV care, and how to address it in a critical population, female sex workers  in South Africa using data and infrastructure from an ongoing adaptive intervention, the Siyaphambili trial.

The study will:

  1. Characterize substance use among the female sex workers living with HIV who participated in the Siyaphambili trial, with a focus on identifying patterns of polysubstance use, using Latent Transition Analysis, their associated determinants (e.g., violence, stigma, economic vulnerability), and if they modify the effectiveness of the sequentially adaptive strategy to improve HIV care outcomes;
  2. Conduct mixed methods formative research on how to deliver substance use treatment for female sex workers in the context of HIV care through  interviews with female sex workers in the Siyaphambili study or in the TB HIV Care (THC) treatment and prevention sex worker program who report any illicit drug use, to ascertain experiences with substances, treatment (e.g. types, relapse), willingness for treatment, and preferences for treatment using a discrete choice experiment;
  3. This data will be supplemented with in-depth interviews with implementation partners (e.g., nurses, clinic management); and
  4. Organize an Implementation Development Workgroup to initiate crosstalk with domestic and international collaborators on substance use in female sex workers to refine emergent implementation strategies for evaluation across contexts.
Abstract on NIH RePORTER