Extended PrEP cascades and determinants of long-acting PrEP intention and unmet PrEP needs among transgender women, transgender men, and non-binary individuals in 20 European countries

Background There is limited information available on PrEP use patterns, and intentions to use long-acting (LA-) PrEP among European trans* individuals. Materials and methods We conducted a cross-sectional survey (PROTECT) in 20 European countries (including France, Germany, Spain, the UK, and Italy, among others) from October 2023 to April 2024. 432 HIV-negative transgender women (n = 60), transgender men (n = 113) and non-binary participants (n = 259) were included in this analysis. We described PrEP cascades, including oral PrEP uptake, adherence (defined as optimal (<25% missed pills for daily PrEP; no missed pills for on-demand PrEP) or suboptimal), discontinuation, LA-PrEP awareness, interest, intention, and unmet PrEP needs that LA-PrEP could address among trans* individuals in a pan-European context. Additionally, we explored the sociodemographic, behavioral, and psychosocial determinants of LA-PrEP intention and unmet PrEP needs in these groups. Final determinants were identified using multivariable logistic regression with stepwise selection to account for confounders. Results 25% of trans* participants were currently using oral PrEP. 23.8% showed suboptimal adherence, and 22.5% had discontinued using PrEP. 23.8% were aware of LA-PrEP, 64.8% expressed interest in, and 59.3% reported an intention to use LA-PrEP, if it were accessible and affordable, leaving 46.1% with unmet PrEP needs. While gender variations existed, differences in LA-PrEP intention and unmet needs were nonsignificant. Shared determinants for LA-PrEP intention and unmet PrEP needs included being a student, being in a monogamous relationship, identifying as bisexual, and perceiving higher HIV-concern and risk. Unmet PrEP needs were associated with being a first-generation migrant (aOR = 2.43, 95%CI:1.08–5.65) and providing transactional sex (aOR = 2.36, 95%CI:1.00–5.76). Conclusions Current oral PrEP use and use patterns remain suboptimal among European trans* communities. However, the high LA-PrEP intention observed among these groups supports its potential to mitigate current unmet HIV prevention needs. Future interventions that aim to leverage and address the identified determinants could be essential to improve PrEP cascade outcomes and ensure an equitable LA-PrEP rollout for trans* populations in Europe.