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French Study Indicates Some Patients Can Control H.I.V. After Stopping Treatment, 'Functional Cure', Visconti Study - NY Times
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NY Times By ANDREW POLLACK and DONALD G. McNEIL Jr.
Published: March 15, 2013
French researchers have identified 14 adults who have been able to control their H.I.V. infection for years after stopping treatment with antiviral drugs, a finding that suggests that some patients might be able to achieve a so-called functional cure.
The report comes only two weeks after doctors in the United States announced that a baby born in Mississippi had apparently been cured of infection with the virus that causes AIDS.
In both cases, scientists said, a crucial element appears to be initiating drug treatment shortly after the infection occurs, though that is not always practical. In the case of the French patients, treatment began within several months of infection, faster than is the case for most adults.
The researchers, who reported their findings this week in the journal PLOS Pathogens, estimated that as many as 15 percent of people who start treatment early and continue for at least a year might then be able to control the virus without treatment, relieving them of a lifelong daily drug regimen.
Asier Saez-Cirion, the lead author of the study, said that the French patients were in a sort of "remission" rather than being cured, because the virus was still present in their bodies, though at low levels.
Still, he said, figuring out why some people seem to be able to control the virus could point the way toward a functional cure by which people might live healthily without drugs even if their infection was not eradicated.
"This is proof of concept that we can induce this status in individuals who were not going to do so naturally or spontaneously," said Dr. Saez-Cirion, an assistant professor at the Pasteur Institute in Paris.
Some AIDS experts agreed. "These people are not cured, but they have some advantages that would be good to understand," said Dr. Myron S. Cohen of the University of North Carolina.
One implication of the French study is that many people now taking antiviral medications might be able to safely stop. But doctors said the study did not provide enough information to predict which patients that might be, and that patients should not stop on their own.
Previous clinical trials have shown that, in general, interruption of treatments leads to worse outcomes.
Dr. Max Essex, chairman of the Harvard School of Public Health AIDS Initiative, said that new tests measuring viral loads in the body are so sensitive that it "might not be a huge risk to take people off treatment for a month" - and quickly put them back on if H.I.V. was to begin multiplying rapidly.
Another implication of the study is that treatment should be started earlier for most people. But that cannot always be done.
"We and others have difficulty identifying and treating such adults so early after infection," said Dr. Douglas D. Richman, director of the Center for AIDS Research at the University of California, San Diego.
Many people are infected for months or years without knowing it. Even if they know it, some do not want to start treatment immediately because of the cost of the drugs or concerns about side effects. The patients in the French study started treatment soon after infection because many had symptoms that sent them to the doctors early, allowing their infection to be detected.
Dr. Saez-Cirion said that most of the patients stopped treatment because they were in studies testing whether patients could take drug holidays. But some just stopped on their own, he said.
The patients were on therapy for one year to seven and a half years. They have been off treatment for 4 to nearly 10 years.
Since stopping treatment, most have had viral blood levels below 50 copies per milliliter, which is considered undetectable. But some have had measurements of up to a few hundred copies.
A small number of people infected with H.I.V. - 1 percent or less - are so-called elite controllers, meaning their bodies keep the virus in check without antiviral drugs. It is possible that some of the French patients might never have needed drugs, but that will never be known because they started treatment so soon after infection.
But the French researchers say the patients, whom they termed "post-treatment controllers," were different from elite controllers.
Post-treatment controllers tended to have very high viral loads soon after infection, while elite controllers are more likely to keep virus levels down, even at the start, the researchers said. The immune systems of the post-treatment controllers also tended to differ in certain ways from those of elite controllers.
The chief barrier to an AIDS cure is that even when drugs sharply reduce the levels of H.I.V. in the blood, the virus can hide out in so-called reservoirs in the body. Dr. Saez-Cirion said that the viral reservoirs in post-treatment controllers were smaller than those of a typical infected person and had a smaller proportion of long-lived immune cells.
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