Subscribe now

Health

Setbacks force HIV researchers to focus on remission, not cures

By Andy Coghlan

11 July 2016

Palm of hand holding pills

Doing away with antiretrovirals remains a distant dream

Aly Song / Reuters

Researchers have acknowledged that we still have far to go in the quest to eliminate HIV infection, and that this goal may be unattainable.

In 2012, the International AIDS Society launched a programme called Towards an HIV Cure, but a series of setbacks have dampened optimism. “A cure is a long way off, and I don’t know if it will ever be achieved,” says Sharon Lewin of the University of Melbourne, Australia.

People with HIV must take antiretroviral drugs for the rest of their lives to keep the virus in check. If they stop their medication, viruses lying dormant in their cells can re-emerge and restart active infection.

Completely eradicating the virus from the body would do away with the need for a constant regime of expensive antiretrovirals. But so far efforts to do this have foundered. One strategy has been to use drugs to flush latent viruses out of their hiding places, but this hasn’t been successful.

There was excitement when some patients who received the drugs soon after infection appeared to be cured. It seemed as if prompt medication had prevented HIV from establishing itself within the body, but in all cases, the virus returned. “We have big challenges predicting when and if the virus will rebound,” says Lewin.

Improving remission

Following these setbacks, the International AIDS Society has now released a new road map, outlining more realistic plans for fighting HIV. Before there can be hope of a cure, researchers need to tackle important gaps in knowledge, including where and how the virus hides, and how to detect the dormant virus. “The challenges remain substantial,” it concludes.

But while a cure remains a long way off, Lewin says there are better prospects for achieving long periods of remission. Early experiments suggest we could develop treatments that keep the virus below detectable levels for long periods without the need for the usual antiretroviral drugs.

“Remission is an important step, and looking forward, we will have different ways to achieve remission, allowing people to come off their usual treatment,” says Lewin.

One way to do this might be through gene editing and gene therapy. These techniques could allow patients’ blood cells to be genetically engineered outside the body to combat the virus, then placed back into the body to keep the virus in check without help from drugs. “We now have a bigger emphasis on long-term immunity, and more confidence about gene therapy,” says Lewin.

To date, only one person has ever been cured: Timothy Brown. He had blood cancer and HIV, and received a bone marrow transplant containing a rare combination of mutated genes that stop the virus from infecting cells. After the transplant, his blood was completely replaced with the HIV-resistant cells, getting rid of the virus for good.

“It’s still only one person, Timothy Brown, so [a true cure] is looking pretty rare,” says Lewin. “But a cure remains an important and aspirational goal.”

Nature Medicine DOI: 10.1038/nm.4108

Topics:

Sign up to our weekly newsletter

Receive a weekly dose of discovery in your inbox! We'll also keep you up to date with New Scientist events and special offers.

Sign up