BACKGROUND: Prevention strategies such as event-driven oral pre-exposure prophylaxis (ED-PrEP) and long-acting injectable PrEP (LAI-PrEP) are emerging as alternatives for adolescents from populations more vulnerable to HIV. We aimed to investigate the awareness and associated factors to intention to use ED-PrEP and LAI-PrEP among adolescents and young men who have sex with men (AYMSM) and transgender women (AYTGW).
METHODS: PrEP1519 is a prospective, multicenter, open-label PrEP demonstration cohort study of AYMSM and AYTGW aged 15–19 in Brazil. For this cross-sectional analysis, we included 597 adolescents enrolled in the cohort from December 2020-March 2022 in the Salvador and São Paulo sites. The outcome variables were the intention to use ED-PrEP and to use LAI-PrEP. The explanatory variables were socio-demographics, sexual behavior, discrimination and violence, and previous use of daily oral PrEP. Descriptive statistics were carried out, and multivariate analysis was conducted to estimate adjusted odds ratios (aOR) and 95% confidence intervals (95%CI).
RESULTS: Only 15.3% and 18.0% of the adolescents were aware of the ED-PrEP and LAI-PrEP options, respectively. Regarding intention to use, 56.4% and 81.5% reported ED-PrEP and LAI-PrEP, respectively. Adolescents with low adherence to daily oral PrEP were more likely to intend to use ED-PrEP (aOR=2.30; 95%CI:1.04–3.08). Those who reported consistent or frequent condom use in insertive anal sex with steady or casual partners were less likely to intend to use ED-PrEP (aOR=0.37; 95%CI:0.15–0.90). As for LAI-PrEP, those with middle (aOR=1.93; 95%CI:1.05–3.53) or low socioeconomic status (aOR=3.13; 95%CI:1.30–7.51) and those who reported three or more casual partners in the previous three months (aOR=2.25; 95%CI:1.30–3.89) were more likely to intend to use LAI-PrEP. Adolescents who never used daily oral PrEP (aOR=0.31; 95%CI:0.11–0.92) were less likely to intend to use LAI-PrEP.
CONCLUSIONS: AYMSM and AYTGW in Brazil reported a low awareness and high intention to use LAI-PrEP over ED-PrEP. Their sexual behavior pattern and previous experience using daily oral PrEP strongly influenced their intention to use the method. Making different modalities available could increase PrEP uptake and may be a potentially good option for adolescents who have not adapted to daily oral PrEP.

Download the e-Poster (PDF)