Approximately 40 million people are currently living with HIV worldwide, and the disease is among the leading causes of death in low-income countries. Though HIV can be treated with combination antiretroviral therapy (ART), successful management of the virus requires continual administration of ART over a patient’s lifetime. This can be challenging in low resource settings. To overcome this challenge, researchers funded by the Common Fund’s High-Risk, High-Reward Research Program aim to develop a long-acting antiviral therapy for people living with HIV that requires only a single administration.

In a major breakthrough, Dr. Leor Weinberger and his colleagues successfully engineered a virus, called a therapeutic interfering particle (TIP), that reduced the levels of HIV in infected mouse cells. TIPs, which consist of harmless pieces of HIV, work by outcompeting HIV for the cellular resources it needs to replicate. Remarkably, TIPs remain effective at reducing HIV’s ability to replicate over time, even if the HIV virus evolves. When the researchers tested TIPs in infected rhesus monkeys, they found that a single administration of the new therapy led to a substantial reduction in levels of simian HIV (an HIV-like virus that infects monkeys) that was sustained during the 6-month study. The rhesus monkeys treated with TIPs also lived significantly longer than control rhesus monkeys during the study’s follow-up period.

Though more research is needed to understand the impact of TIPs in people living with HIV, this work represents an important breakthrough in the development of a long-acting, single-administration antiviral HIV therapy. For more information on this groundbreaking research, read this New York Times article and listen to this interview with HRHR awardee Dr. Leor Weinberger:

Reference: Engineered deletions of HIV replicate conditionally to reduce disease in nonhuman primates. F.N. Nagoor Pitchai, E.J. Tanner, N. Khetan, G. Vasen, C. Levrel, A.J. Kumar, S. Pandey, T. Ordonez, P. Barnette, D. Spencer, S-Y. Jung, J. Glazier, C. Thompson, A. Harvey-Vera, H-I. Son, S.A. Strathdee, L. Holguin, R. Urak, J. Burnett, W. Burgess, K. Busman-Sahay, J.D. Estes, A. Hessell, C.M. Fennessey, B.F. Keele, N.L. Haigwood, L.S. Weinberger. 2024 Aug 9, epub.