With researchers announcing last week that they “functionally cured” a baby with human immunodeficiency virus, talk has turned to curing others of the virus. But AIDS researchers, including those who treated the baby, caution that it is too soon to tell whether other HIV-infected children, who have been given antiretroviral drugs such as AZT from infancy, can also safely stop their medications.
That is partly because tests conducted at the University of Massachusetts Medical School in Worcester show that traces of the virus remain in the infant.
“We’re calling this a functional cure, rather than a complete cure, because when we do ultrasensitive tests, we’re detecting, on occasion, very low levels of viral DNA in [the child’s] cells,” said Dr. Katherine Luzuriaga, a UMass immunologist who analyzed the baby’s blood and helped present the findings at an AIDS conference in Atlanta.
Luzuriaga was brought into the case by a University of Mississippi Medical Center physician who made the initial HIV diagnosis and started treating the newborn, now 2 years old, with a three-drug cocktail within two days of birth.
“We definitely want to follow this baby over a longer period of time,” Luzuriaga said, adding that treatment could be resumed if the actual virus is again detected in the blood.
She and her colleagues believe the baby’s early treatment may have halted the formation of millions of dormant cells, called reservoirs, that carry the DNA of the virus, are not eradicated by treatment, and trigger a recurrence of the virus in most patients who stop taking anti-retroviral drugs.
Luzuriaga, whose lab receives several million dollars annually from the National Institutes of Health, has been investigating the impact of early treatment on HIV-infected infants for the past two decades.
She and her colleagues also presented data at the conference describing a potential eradication of HIV in five infected teenagers who have been taking anti-retroviral drugs since about two months after they were born. In comparison, the virus was less successfully controlled in four teenagers who began treatment later in infancy.
“We’re conducting further studies on these five teens to see whether it would be safe or prudent to consider a trial off of anti-retroviral therapy,” said Luzuriaga.
That would need to be done under research conditions with careful monitoring to ensure that the virus does not come back full-force, she said.
“We certainly do not want to recommend to parents or physicians taking care of children infected with HIV that they should try to stop the therapy to see if the child has been cured,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, which provides funding for HIV research conducted by Luzuriaga and others.
But thousands of children and young adults in this country who have been treated for HIV since infancy, often with no detectable signs of the virus, could be candidates for future studies to test whether they have been cured.
“We in the field may have cured some babies without realizing it, and they may still be on the drugs through childhood, so it’s important to study this further,” Fauci said.