PrEP Adherence and Effectiveness Are High in Real-World Settings

Treatment with pre-exposure prophylaxis (PrEP) is associated with low incidence of HIV, particularly in a setting of affordable PrEP, according to the results of a recent study.

“Daily pre-exposure prophylaxis (PrEP) is effective in preventing HIV, but few long-term data are available on effectiveness and adherence in real-world settings,” the researchers wrote.

In order to examine trends in HIV incidence in high-risk patients prescribed PrEP, the researchers conducted a prospective, single-arm implementation study of daily oral PrEP in 31 sites across Australia. Participants were HIV-negative adults at high risk of HIV infection. All participants were prescribed tenofovir disoproxil fumarate (300 mg) and emtricitabine (200 mg).

Overall, 9596 participants were given PrEP, and 9520 had at least 1 HIV test available during follow-up. The mean medication possession ratio decreased from 0.93 to 0.64 from the first to the ninth quarter, and there were 30 HIV seroconversions during 18,628 person-years (incidence of 1.61 per 1000 person years).

Increased HIV incidence was associated with younger age, living in an area with fewer gay men, reporting more risky behaviors, and having MPR of less than 0.6. During the final year of the study in which PrEP was purchased rather than provided by the researchers, HIV incidence was 2.24 per 1000 person-years.

“HIV incidence remained low over up to 3 years of follow-up, including during a transition from study-provided to publicly subsidised PrEP. In a setting of affordable PrEP and associated health-care services, very low HIV incidence of 1 to 2 per 1000 person-years can be maintained in gay and bisexual men who were previously at high risk.”

—Michael Potts

Reference:

Grulich AE, Jin F, Bavington BR, et al. Long-term protection from HIV infection with oral HIV pre-exposure prophylaxis in gay and bisexual men: findings from the expanded and extended EPIC-NSW prospective implementation study. Published online July 1, 2021. Lancet HIV. https://doi.org/10.1016/S2352-3018(21)00074-6