Background: PrEP is efficacious for HIV prevention; however, effectiveness needs to be evaluated in community settings and populations most vulnerable to HIV, including black MSM and TGW in the United States (US). We compared the effectiveness of enhanced PrEP (EPrEP) adherence support to standard of care (SOC) PrEP among black MSM and TGW attending a community clinic in New York City.
Methods: EPrEP included behavioral interventions (peer navigation, live and online support groups, and SMS text messages). Interviews at baseline and 6-months assessed potential correlates of adherence including depressive symptoms, substance use, and homelessness. Self-reported adherence over previous 30 days was collected using a validated, structured questionnaire. The sample was divided into quartiles; the top quartile (≥87% adherence) was considered ''adherent.'' Those in other quartiles were considered non-adherent, along with those who missed interviews. Adherence was analyzed using intent-to-treat (ITT) and as-treated (AT) methods. Crude and adjusted analyses examined factors associated with being adherent.
Results: 204 participants (194 MSM and 10 TGW) were enrolled and randomized to EPrEP or SOC PrEP. Figure 1 shows the adherence distribution by study arm using ITT and AT analyses. Of 204 participants, 76 (37.3%) did not complete the 6-month interview and were assigned 0% adherence; there was no difference by study arm (p=.29). Of the EPrEP group, 28 (27.7%) were adherent, compared to 26 (25.3%) in the SOC PrEP group (p=.69). In the AT analysis, 28 (41.8%) in the EPrEP group were adherent, compared to 26 (42.7%) in the SOC group (p=.92). As shown in Table 1, variables predicting lower non-adherence in the unadjusted analysis include lower educational attainment, not working, having Medicaid/Medicare, and having marginal housing. Study arm was not a significant factor. In multivariable analysis, only education remained significant.
Conclusions: A substantial proportion of participants were lost to follow-up and no difference was noted in adherence between EPrEP and SOC PrEP arms. Structural factors including education and employment impacted adherence. Findings suggest the need to develop and test interventions targeting multi-level factors associated with PrEP retention and adherence among groups most impacted by HIV, including black MSM and TGW in the US.