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Study finds significant benefits from early HIV treatment

The fear and stigma that surrounds the human immunodeficiency virus (HIV) is unnecessarily great. The treatment for HIV is becoming increasingly sophisticated and effective, to the point where early treatment of HIV can reduce the risk of viral transmission between partners to very low levels.

The main treatment for HIV is antiretroviral therapy (ART). ART reduces a patient’s viral load and in doing so, reduces the likelihood of HIV transmission between sexual partners. In the past, ART was commenced when patients had a low CD4+ cell count or had an illness that was caused by their weakened immune system. However, there is increasing evidence to suggest that early initiation of ART, regardless of CD4+ count, reduces the likelihood of partner transmission.

CD4+ cells are white blood cells that are vital in fighting infection. They are selectively infected by HIV and are then destroyed by the body as a means of eliminating the virus. A low CD4+ count is a sign of more advanced HIV infection.

A recently published study in the New England Journal of Medicine has shown that early initiation of antiretroviral therapy (ART) leads to a 93% reduction in the rates of HIV transmission between sexual partners when compared with delaying ART.

The study randomised 1,763 patients with HIV infections. Half of the group received ART on enrolment into the study (early ART) and the other half had delayed ART that was initiated when they had a reduced CD4+ count or were sick with an immune-deficiency-related illness. During the study period of 5 years, the early treatment group only had 3 documented viral transmissions, whereas the delayed ART group had 43 transmissions. The participants were genetically tested to ensure that they were being infected by the same strain of virus.

Delaying ART was stopped early because of this significant finding and every participant was offered ART at 1.7 years into the study. Despite this early cross-over in treatment groups, lower rates of infection were still noted in the early ART group 5 years later.

The study also showed, as predicted, that an increased viral load was associated with a higher risk of partner-transmission as well as less frequent condom use.

The guidelines for ART have since been changed to recommend early treatment of HIV, rather than delaying treatment until patients have a low CD4+ count. Of course, the benefits need to weighed against the risks in each individual situation, but it is reassuring to know that early treatment can significantly reduce the chance of partner transmission.

Reference:

Cohen, Myron S. et al. "Antiretroviral Therapy For The Prevention Of HIV-1 Transmission". New England Journal of Medicine (2016): n. pag.