Effects of test-and-treat versus preexposure prophylaxis on elimination of HIV transmission: analysis of 24 HIV prevention trials.

Abstract

Introduction: In 2023, 28.8 million (72%) of 39.9 million people with HIV (PWH) worldwide were on treatment with viral suppression, while 11.1 million (28%) people had viraemia with the risk of onward HIV transmission. That year, there were 1.3 million new HIV infections worldwide. To achieve elimination of HIV worldwide by 2030, we need a combination of intensive HIV testing and treatment, as well as preexposure prophylaxis (PrEP). We aimed to assess the relative effectiveness of HIV testing and treatment versus PrEP for the elimination of HIV, by comparing the prevalence and incidence of HIV in prevention clinical trials.

Methods: Systematic reviews for PrEP and HIV vaccine trials in Medline, Embase and Pubmed databases were performed, with search terms 'PrEP', 'HIV' and 'efficacy'. The primary outcome was the rate (ratio) of prevalence at screening compared to the incidence of HIV in the control arm.

Results: Of 5106 records, 19 PrEP and 5 vaccine trials were included. The mean prevalence/incidence ratio was 3.5 (range 0.1-16.1); For every HIV acquisition prevented by PrEP, 3.5 PWH were diagnosed and treated at the screening phase of the trials.

Conclusion: The main benefit of clinical trials of PrEP and vaccines on community viral load was at the screening phase. This analysis underscores the continued importance of testing and treatment for the elimination of HIV transmission worldwide. Funding for HIV testing and treatment should not be diverted to rollout of expensive long-acting antiretrovirals for PrEP, especially in high-prevalence countries.