There Is No Cure for HIV-But Scientists May Be Getting Closer

There Is No Cure for HIV-But Scientists May Be Getting Closer
From TIME - March 10, 2018

Cure isnt a word normally used in the context of AIDS. For most of the 35 years since HIV, the virus responsible for the disease, was first identified, doctors have viewed the notion of a cure as more fantasy than fact.

Thats because HIV is a virus unlike any other. It disables the very immune cells that are supposed to destroy it and also sequesters itself in the bodys cells, staging the ultimate deadly ambush whenever the immune defenses guard comes down, months or sometimes even years later.

Yet for the first time in the HIV epidemic that currently affects nearly 37 million people worldwide, some experts are starting to aim for a curecautiouslyas they fashion the next generation of HIV treatments. Scientists now understand how HIV burrows itself inside cells and remains cloaked from the immune systems watchful gazeand they have some ideas about how to expose and annihilate it. The National Institutes of Health (NIH) is funding HIV cure efforts based on this new knowledge, and advocacy groups like amfAR are also pouring resources into not just treating HIV, but also finding ways to eradicate it completely.

Absolutely HIV can be cured, says Rowena Johnston, vice president and director of research for amfAR. The bazillion-dollar question is how.

Doctors today have no trouble keeping HIV under control in people who are infected, thanks to antiretroviral (ARV) drugs, which stop the virus from replicating once it finds its way inside healthy cells. If it is not making more copies of itself, HIV cannot spread to infect new cells. That translates into healthier, longer lives for people who are HIV-positive.

Yet as powerful as the current drug treatments are, they need to be taken daily to keep the virus suppressed, and they cant actually rid the body of infected cells. For self-preservation, some HIV does not actively pump out more copies of itself, but instead lies dormant inside certain immune cells. The drugs are remarkably good at stopping the virus from replicating, says Dr. Robert Siliciano, professor of medicine at Johns Hopkins University School of Medicine, who first identified these sleeping virus reservoirs. The problem is that there is also a form of HIV that is not replicating and is latent, that is not affected by the drugs and not seen by the immune system. These are the viruses that come roaring back when people stop taking their medications, or take them erratically.

But in the latest report presented this month at the Conference on Retroviruses and Opportunistic Infections in Boston, researchers revealed the strongest evidence yet that these latent viruses can be activated and eliminated, at least in animals. In a study involving a form of HIV that infects monkeys, Dr. Dan Barouch and his colleagues at Beth Israel Deaconess Medical Center and Harvard Medical School showed that a drug that stimulates the immune system and activates the dormant HIV, combined with a powerful antibody that can neutralize the HIV-infected cells, prevented HIV from surging back in five of 11 animals, six months after they stopped taking ARVs. In the monkeys whose HIV did return, the virus levels were 100 times lower than they were in animals that were not treated at all.

I think our data raises the possibility that an intervention achieving a functional cure is possible, says Barouch. It shows a level of potential efficacy, at least in animals, that to the best of my knowledge hasnt been seen before.

The fact that nearly half of the animals did not show the typical spike in HIV that normally comes within two weeks of stopping anti-HIV drugs suggests that Barouchs so-called shock and kill approach may be effectively targeting that elusive reservoir of dormant virus.


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