Immunotherapy shows promise as HIV treatment: study

Immunotherapy has been considered a potentially promising for many different kinds of cancer, and now there is fresh hope that the same method could be used to treat or functionally cure HIV, U.S. researchers said Wednesday.

The study, published in the New England Journal of Medicine, examined a total of 24 chronically HIV-infected participants in clinical trials conducted at the University of Pennsylvania (Penn), the University of Alabama at Birmingham, and the U.S. National Institutes of Health.

It found injections of one broadly neutralizing HIV antibody (bNAb), known as VRC01, were safe, generated high levels of the antibody and modestly delayed the time of HIV viral rebound, but suppression did not surpass eight weeks in the majority of participants.

Senior author Pablo Tebas, director of the AIDS Clinical Trials Unit at Penn, said the study only looked at one antibody and they believe combinations of more potent bNAbs may help successfully control the AIDS virus.

As a result, this method marks a first step toward the ultimate goal of durable suppression of HIV in the absence of antiretroviral therapy, Tebas said.

"For the near future, it is unlikely that we will be able to fully eradicate HIV once a person has been infected. But a functional cure is a reasonable intermediate goal," he said in a statement.

A functional HIV cure means that while the virus would still exist in a person's body in extremely small amounts, virus replication would be durably suppressed, disease progression drastically slowed, and symptoms of infection stopped -- all without the need for daily medications.

"The goal of immunotherapy is to eliminate the need to take a pill every single day while simultaneously chipping away at the latent reservoir of virus-infected cells. However, we are still years away from that goal. And even if a person is able to be functionally cured of HIV, long-term follow-up will be essential to ensure that the virus doesn't return to high levels," Tebas said.

But many participants were also found to have HIV that was resistant to the bNAb long before they entered the trial.

The researchers identified this pre-existing resistance as a barrier to effective antibody-based immunotherapy.

Currently, most people living with HIV take a once-daily combination of antiretroviral therapy, which prolongs life expectancy and improves overall health, but cannot completely eradicate the virus.

However, adherence to a daily HIV medication continues to be a challenge for many people living with HIV, especially in resource-limited settings, and the vast majority of people living with HIV would experience rapid rebound if antiretroviral therapy is stopped or interrupted. Enditem