Researchers have developed a new antibody-based drug that has the potential to slow down the replication of the human immunodeficiency virus (HIV) in the body and may also provide a better strategy for long-term control of the deadly infection. Anti-retroviral therapy — a combination of drugs that slows the replication of HIV in the body — currently used to treat HIV has drawbacks. If a person discontinues his or her treatment, even missing a few doses, the level of the virus in the body is able to rebound quickly.
In the antibody therapy, the researchers used 3BNC117 — a molecule — also called as a broadly neutralising antibody because it has the ability to fight a wide range of HIV strains. The findings of the first clinical trial showed that using the antibody could greatly reduce the amount of virus that is present in an individual’s blood. “This study provides evidence that a single dose of an antibody stimulates patients’ immune response, enabling them to make new or better antibodies against the virus,” said lead author Till Schoofs, postdoctoral fellow at The Rockefeller University in the US.
For the study, published in the journal Science, the team included 15 patients, in the clinical trial, who had high levels of the virus in their blood, and 12 other patients whose virus levels were being controlled with antiretroviral therapy (ART). The patients were infused with a single dose of 3BNC117 and were monitored over a six-month period.
In 14 out of 15 patients who had higher levels of the virus at the time they were given the antibody were seen making new antibodies that could neutralise a number of different strains of HIV. It usually takes several years for the body to begin to make good antibodies against HIV. So there might be an even better effect later on, especially if patients are given more than one dose of 3BNC117, the researchers added. To determine further benefits of treatment with 3BNC117, the researchers conducted another study, also published in the journal Science, in a mouse model.
The results revealed that 3BNC117 was able to engage the animals’ immune cells and accelerate their clearance of HIV-infected cells. “This shows that the antibody not only can exert pressure on the virus, but also can shorten the survival of infected cells,” first author of the study Ching-Lan Lu, doctoral student at The Rockefeller University, noted. Further, the researchers plan to test 3BNC117 in combination with other antibodies that target HIV, to determine whether an even stronger antiviral effect can be found.