Postexposure prophylaxis, preexposure prophylaxis or universal test and treat: the strategic use of antiretroviral drugs to prevent HIV acquisition and transmission

Abstract

This review considers the use of antiretroviral drugs specifically to prevent HIV transmission. Antiretroviral therapy (ART) can be implemented for the protection of uninfected individuals both before (preexposure prophylaxis) and after (postexposure prophylaxis) exposure to HIV infection. Preexposure prophylaxis may be used coitally dependently when individuals are intermittently exposed or by continuous daily dosing for those constantly exposed; postexposure prophylaxis is used in 28-day courses. Alternatively, ART can be used strategically to reduce the viral load and consequent infectiousness of an HIV-infected individual, thereby limiting the risk of onward viral transmission. A policy of universal HIV testing to enhance the identification of all HIV-positive individuals followed by immediate treatment of all HIV-positive individuals, irrespective of their CD4 cell counts (universal test and treat), has been postulated as a potential tool capable of reducing HIV incidence at a population level. This concept represents a paradigm shift in the use of ART, targeting infectious individuals for prevention rather than protecting uninfected exposed populations. This strategy could have the advantage of preventing transmission and reducing HIV incidence at a population level, as well as delivering universal access to therapy for all people living with HIV and AIDS, potentially eliminating mother-to-child HIV transmission and limiting concomitant diseases such as tuberculosis. This review critically examines the scientific basis of ART for HIV prevention, summarizing the risks and opportunities of the potential expansion of ART for prevention. Specifically, we consider the evidences for and against targeting HIV-uninfected individuals compared with enhanced HIV testing and treatment of HIV-infected individuals in terms of impact on viral transmission.

Successes and challenges of HIV prevention in men who have sex with men

“…34 The implications of this finding for HIV prevention in MSM are not immediately clear. Very few same-sex couples were included in the study, and a separate analysis of efficacy in MSM was not possible.…”

Beyond Condoms: Risk Reduction Strategies Among Gay, Bisexual, and Other Men Who Have Sex With Men Receiving Rapid HIV Testing in Montreal, Canada

“…Yet recent studies have found that 8–20 % of MSM had never been tested for HIV and only 60 % had been tested in the past 12 months [32, 61, 62]. Post-exposure prophylaxis [PEP], the provision of antiretroviral drugs after a possible exposure to HIV [63, 64], can stop an HIV infection from taking hold if taken within 1–3 days of exposure [59, 63, 65–67]. In a range of studies among MSM, 36–48 % of participants said they were aware of PEP [68–70] but only 1.9–6.3 % had used it [32, 68, 69, 71, 72] reflecting a broader trend in which use of PEP by MSM has remained well below 10 %.…”

The Development and Validation of an UHPLC–MS/MS Method for The Rapid Quantification of The Antiretroviral Agent Dapivirine in Human Plasma

“…While antiretroviral drugs have shown efficacy in the treatment of HIV infection, antiretroviral drugs have also been successfully used for HIV prevention in a variety of settings, including pre-exposure prophylaxis in HIV-uninfected individuals (PrEP) and as ‘treatment as prevention’ in HIV-infected individuals, following either oral or vaginal administration [6-12]. Topical microbicides are vaginally or rectally administered products designed to prevent HIV transmission at the site of acquisition [2,13-15].…”