Treatment as Prevention

The treatment-as-prevention or test-and-treat approaches to HIV prevention refer to the use of ARVs by people living with HIV to lower their viral load and hence the potential to transmit HIV. In 2010, R&D invested toward interventions testing the prevention effect of ARV treatment equaled US$19.6 million. This funding went toward the NIH funded HIV Prevention Trials Network (HPTN) 052 and HPTN 065 trials.

In May 2011, HPTN 052, upon the recommendation of its data and safety monitoring board (DSMB), released results from 13 sites in Botswana, Brazil, India, Kenya, Malawi, South Africa, Thailand, the United States, and Zimbabwe. HPTN 052 is a randomized trial examining the HIV prevention effect of early initiation of treatment in couples where one partner is HIV-positive and the other is not. The trial found a 96% reduced risk of transmission in those couples, as well as a reduction in extra pulmonary tuberculosis among HIV-positive participants in the delayed treatment group. The HPTN 065 community level trial taking place in the District of Columbia and the Bronx, New York, which is designed to test strategies to increase community HIV testing, improve referrals to treatment, and increase adherence to treatment regimens.

A number of treatment-as-prevention studies are planned but as yet unfunded. In South Africa, the French National Agency for Research on AIDS and Viral Hepatitis (ANRS) announced plans for a trial providing universal HIV testing and treatment in order to study the impact it would have on HIV transmission. As part of the PopART program, the Imperial College London is planning a study in Uganda and Zambia that tests the effectiveness of universal HIV voluntary counseling and testing (VCT) with immediate access to antiretroviral therapy (ART) as an intervention to reduce transmission. In Malawi, HIV-positive individuals in acute infection are being offered early treatment and behavior interventions in the NIH-funded MP3 study, which is also examining the impact on HIV incidence. Finally, in Swaziland, a Clinton Foundation project is under consideration which would offer universal HIV testing and treatment.