Decline in HIV Infections Among High-Risk MSM After Aggressive PrEP Rollout in Australia

Decline in HIV Infections Among High-Risk MSM After Aggressive PrEP Rollout in Australia

Aggressive rollout of preexposure prophylaxis among high-risk MSM in New South Wales was associated with a 31% decline in new HIV infections compared with the previous year.

This study was undertaken to assess the effect on HIV incidence of rapid, targeted, high coverage rollout of preexposure prophylaxis (PrEP) for men who have sex with men (MSM) in Australia’s most populous state, New South Wales. The partially manufacturer-funded study recruited primarily high-risk MSM within a network of 21 clinics who were provided free daily coformulated tenofovir disoproxil fumarate and emtricitabine. The primary endpoint was the within-cohort HIV incidence and change in overall new HIV diagnoses for the region comparing the 12-month periods before and after PrEP rollout.

Researchers recruited 3700 participants (median age, 36) from March 1 to October 31, 2016. During 4100 person-years, two participants became HIV infected; both were nonadherent to PrEP. The HIV incidence among MSM in New South Wales decreased by 31.5% after the rollout despite reported increased rates of condomless anal intercourse and sexually transmitted diseases. Subsequently, as of October 31, 2017, the total number of study participants increased to 7621 representing an estimated 19.6% of sexually active HIV-negative or HIV-status unknown MSM in the region (before the program only 3.9% reported ever using PrEP). Public funding of PrEP became available in Australia on April 1, 2018, coupled with information campaigns promoting PrEP use for MSM. The authors conclude that PrEP roll-out should be a high priority for jurisdictions where new HIV occurs mainly in MSM.

COMMENT

In the absence of a controlled trial with a comparison group, determining the sole effect of PrEP on HIV incidence is not possible. PrEP rollout resulted in increased PrEP use in the target population. In addition, despite the already-high regional use of antiretroviral therapy among HIV+ MSM (estimated to have already exceeded the UNAIDS 90-90-90 target by 2016), PrEP rollout was followed by a sharp decline in incident HIV cases. This experience strongly supports the view that aggressive use of PrEP can further accelerate reduced HIV transmission when the epidemic is concentrated among MSM.

Keith Henry, MD reviewing Grulich AE et al. Lancet HIV 2018 Oct 17