Is a functional cure for HIV infection possible?

HIV infection may be cured in two different ways: Treatment could eliminate all HIV from the body, or it could remove most of the HIV leaving some residual virus which would not cause disease. The latter is termed a “functional cure” and researchers presenting at the 20th Conference on Retroviruses and Opportunistic Infections (CROI) have reported an infant born with HIV to have been functionally cured.

The baby was born prematurely and tested positive for HIV virus. At 30 hours of age, clinicians at the University of Mississippi Medical Center immediately administered intensive antiretroviral treatment (ART) which decreased virus to levels only detectable by ultrasensitive tests at 29 days after treatment. Treatment was continued until 18 months when the child was lost to follow up and ART discontinued. Unexpectedly, when the child later returned to the clinic at 2 years of age, repeated tests showed only undetectable or minute quantities of HIV in the body.

The question that immediately comes to mind is whether the infant was really infected by HIV, or if the virus was merely passed from the mother to child but actually did not become established in the infant. There have been other reports of this phenomenon. Antiretroviral treatment in this case would have operated in a preventive rather than a curative manner. However, according to the work presented, the child tested positive for HIV virus at various times and on different samples arguing that the virus did establish itself and the infant was indeed infected.

Since HIV establishes a reservoir of persistently infected cells in the earliest stages of infection, there is growing interest in the idea of early intensive antiretroviral treatment to limit the size of this reservoir and as such lead to a functional cure. Since babies are infected most often in the final phases of pregnancy or during labor, they present an ideal situation to prevent or limit the HIV reservoir. In a sense, the case of the Mississippi infant was an unplanned experiment since the infant started treatment early and stopped at 18 months. It opens possibilities for further research in controlled clinical trials for preventing the 1000 daily HIV infections still occurring in infants throughout the world.

This post has been simultaneously published on the Huffington Post's Spanish edition.