Single antibody infusions found promising against HIV

New York: A single antibody infusion can protect monkeys against infection with an HIV-like virus for up to 23 weeks, researchers have found.

The findings suggest that using infusion of broadly neutralising antibodies (bNAbs) as a prevention strategy potentially could protect people at high risk for HIV transmission. 

The study, published in the journal Nature, was led by scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the US National Institutes of Health, and The Rockefeller University in New York.

In the study, the researchers rectally exposed macaques to weekly low doses of simian human immunodeficiency virus (SHIV), which contains components of HIV and a related monkey virus. 

On average, it took three weeks for detectable levels of virus to appear in the blood of untreated animals.

To investigate whether bNAb infusion could offer long-term protection against SHIV infection, the scientists gave single infusions of one of three individual bNAbs against HIV to three groups of six macaques, then exposed the animals weekly to low doses of SHIV. 

In all cases, the bNAb infusions delayed the acquisition of SHIV, with the longest period of protection lasting 23 weeks. 

The researchers found that the duration of protection depended on the antibody's potency and half-life - a measure of the antibody's lifespan in the blood and tissues.

Enrollment for the first of two planned human clinical trials assessing one of three individual bNAbs infusions for preventing HIV infection has already begun, the study pointed out.