End-user perspectives are vital to the design of new biomedical HIV prevention products. Behaviorally congruent alternatives to condoms and daily oral Pre-Exposure Prophylaxis (PrEP) remain crucial. MTN-035 evaluated the acceptability of and preference for three placebo, non-gel delivery vehicles (insert, enema, suppository) that could be used to deliver PrEP prior to receptive anal sex (RAS).
We enrolled 217 HIV-negative, cisgender men who have sex with men (MSM) and transgender people ages 18–35 into a randomized cross-over trial across 7 sites in the United States, Peru, Malawi, South Africa, and Thailand. Participants were asked to use each product prior to RAS over 4-week periods. At the final study visit, product-experienced participants completed a conjoint experiment where they selected between random sets of product profiles using 7 features (delivery vehicle, timing of use before sex, side-effects, duration of protection, efficacy, frequency of use, and need for a prescription). A subset of participants completed an exit in-depth-interview (IDI; n=70).
Participants identified as cisgender men (172; 79.3%), transwomen (42; 19.4%) or transmen (3; 1.3%). Mean age was 24.8 (SD=4.7 years). Product-experienced participants had heterogeneity in top-ranked product choices across scenarios (Table 1). In conjoint analyses, efficacy was the strongest determinant of stated choice overall (30.4%), followed by product delivery vehicle (18.0%), and side-effects (17.2%). The most common chosen combination of attributes was an enema used ~ 30 minutes before sex, with 95% efficacy, offering a 3-5 day protection window, used weekly, having no side effects, and available as an over-the-counter product. In IDIs, participants’ acceptability across products were informed by the aforementioned features, RAS-related characteristics (e.g., lubricity; hygiene), personal considerations (e.g., relationship status), and social context (e.g., stigma).
Choice in next generation PrEP products, informed by acceptability and personal preference, is highly desired by MSM and transgender people. MTN-035 participants weighed product features differently, recognizing the potential to create diverse, behaviorally congruent biomedical options that fit the needs of intended end-users. Rather than one-size fits all, our findings underscore the variations in acceptability of non-gel delivery vehicles for local biomedical prevention prior to RAS.
