Efficacy of a Trauma Intervention for Affect Regulation, Adherence, and Substance Use to Optimize PrEP for Women Who Inject Drugs

In the United States, recent outbreaks coast-to-coast forewarn of a possible resurgence of HIV, especially among women who inject drugs (WWID), particularly if access, uptake, and adherence to effective harm reduction tools remain sub-optimal. Pre-exposure prophylaxis (PrEP) is a user-driven method that safely and effectively prevents HIV. While we have shown that cisgender WWID consider PrEP beneficial and are willing to accept a prescription, consistent with the well-known SAVA syndemic framework, social stigma, economic insecurity, traumatic experiences (or the threat of violence), and drug use greatly undermined their agency to prioritize and adhere to PrEP. This trauma-informed randomized control trial (RCT) will address the urgent need for HIV prevention interventions, informed by the SAVA framework, that produce durable reductions in HIV risk among WWID. We will integrate contingency management (CM), a proven strategy to reduce drug use and HIV risk, and expressive writing (EW), a safe and effective approach for addressing trauma symptoms, in order to test whether EW delivered during CM (EW+CM) produces durable reductions in HIV acquisition risk compared to an attention-control condition. We will leverage our partnership with Prevention Point Philadelphia (PPP), the largest syringe exchange in the mid-Atlantic, and Courage Medicine to recruit 240 WWID who will (re)initiate PrEP at PPP or Courage Medicine. Once enrolled they will immediately begin a 3-month CM period that provides incentives for directly observed daily oral PrEP doses or confirmed injectable PrEP doses, stimulant/opioid abstinence (measured thrice weekly through urine screening), and completion of four writing sessions. After a run-in period, WWID will be randomized to either EW+CM (n=120) or Neutral Writing+CM (n=120). Follow-up assessments will occur at 3-, 6-, and 12-months post-randomization and will include objective measures of PrEP adherence over time. A subset of WWID from both arms will complete qualitative interviews at 3- and 12-months. All study activities and daily PrEP dispensing will occur at PPP. The specific aims are to: (1) Determine the efficacy of EW+CM for improving the proportion of participants achieving reductions in HIV acquisition risk (operationalized as the proportion of WWID reporting syringe sharing or condomless sex during objectively measured periods of PrEP non-adherence) at 12 months. (2) Examine key secondary outcomes such as greater PrEP persistence, reductions in substance use, PTSD symptoms, and depression, as well as entry into drug treatment over 12 months. (3) Evaluate the pathways through which the intervention operates using qualitative interviews, mediation analysis (e.g., emotional expression and processing in EW essays), and moderation analysis (e.g., more pronounced among those with higher PTSD severity at baseline). This RCT could have an exceptional impact by yielding one of the first evidence-based interventions to address HIV acquisition risk in the era of PrEP among WWID.