PrEP demand creation strategies for adolescents at increased risk of HIV infection in São Paulo, Brazil: a cost-consequence analysis.

Background: The extension of PrEP coverage for vulnerable populations depends on demand creation strategies that aim to inform, encourage usage, and facilitate access to health services. However, there are no cost estimates for Brazil or Latin America regarding demand creation strategies focused on populations with higher vulnerability and risk of HIV infection. This analysis aims to assess the costs and health outcomes of different strategies used to create demand for PrEP for individuals aged 15 to 19 who identify as men who have sex with men (MSM), transgender women (TGW), or non-binary people assigned male at birth.

Methods: Cost-consequence analysis of six demand creation strategies used in the "PrEP1519 Study" (chatbot strategy; dating apps strategy; social media strategy; socialization places strategy; NGOs strategy; direct referrals strategy). The analysis was conducted using data from January 2019 to December 2021. The evaluated outcome was the "PrEP initiation ratio" (PrEPIR), which represents the percentage of approached individuals who started PrEP. The cost analysis included direct costs related to personnel, promotional materials, testing, equipment, and services.

Results: The strategy with the highest PrEPIR was the social media strategy (2.97% [95% CI 2.29-3.84]), followed by the socialization places strategy (2.05% [1.45-2.89]). The direct referrals strategy, which served as the baseline, had one of the lowest PrEPIR (0.36% [0.30-0.43]). The average cost per participant included ranged from $100.74 for the direct referrals strategy to $5,572.00 for the chatbot strategy. The strategy with the highest total cost was the chatbot strategy ($55,719.98), whereas the strategy with the lowest total cost was the NGOs strategy ($10,809.80).

Conclusion: Despite incurring higher costs, the implementation of more successful demand creation strategies (such as socialization places, social media, and dating apps) has the potential to increase PrEP usage and, consequently, reduce HIV infection in populations facing greater vulnerability. These findings can contribute to more effective planning and organization of prevention programs by healthcare services to reach these populations.

Trial registration: This analysis is part of the "PrEP1519 Study" (protocol number 89993018.9.0000.0065).