In experiments with humanized mice—animals whose immune system has been modified to resemble that of humans—04_A06 permanently reduced the HIV viral load to undetectable levels. Most other HIV antibodies, in contrast, only achieve short-term effects in this animal model, as resistance develops quickly. The study “Profiling of HIV-1 elite neutralizer cohort reveals a CD4bs bNAb for HIV-1 prevention and therapy” is published in Nature Immunology.

Antibodies are protein molecules of the immune system that specifically attack pathogens. Identifying an effective HIV antibody is a known challenge, given that the virus is constantly changing. As a result, many antibodies can only block certain variants of the virus.