Second baby cleared of HIV. Rare event, or hope for others?

In only the second documented case of its kind, an infant born with the AIDS virus may have been cured of the infection, thanks to an intensive drug treatment begun just hours after her birth. The baby girl — now 9 months old — from Long Beach, Calif., is still on that regimen of antiretroviral drugs. But researchers who described her case at an AIDS meeting in Boston this week say advanced testing suggests that she is HIV-negative.

The California child's case comes three years after doctors apparently cleared an infant in Mississippi of her HIV infection shortly after she was born. That child is now a healthy 3-year-old who seems to be free of HIV, doctors say, despite having been off the AIDS drugs for almost two years now. Researchers are eager to determine if the two remarkable cases are rare experiences or a broader sign of hope for the hundreds of HIV-infected babies born each day. To find out, clinical trials involving roughly 60 newborns will begin as early as this April or May, says Dr. Anthony Fauci, who directs the National Institute of Allergy and Infectious Diseases. Fauci, whose institute funded the research in both cases, sat down on Thursday with NPR's Audie Cornish, for All Things Considered, to talk about the two children, and what their promising experience might mean for the future. Here's an edited excerpt of their conversation: How is this course of treatment different from what's usually given to babies infected with HIV?

In the usual situation when a baby is born to an infected mother, you don't know at birth, for sure, if the baby is infected. So what you do is you give the baby what's called a preventive type of drug [regimen] — lower dose and [fewer drugs]. When you find out that the baby is ultimately infected, you switch over to the full component of three drugs at the right dose, to start treating them. ... The original Mississippi baby and the baby from California were treated within hours of birth as if they were infected. So instead of giving them the prevention type of drug over a period of a few weeks, they were immediately given the full-blown course of the treatment drugs.

But how did doctors know when to stop treatment in the first case — the little girl born in Mississippi?

The doctors would never have just ... stopped drug [treatment] in the baby after several months. The mother was lost to follow up and [she apparently] stopped giving the drug to the baby. And then when [the mother and child] came back, the physician noticed that [the little girl] had been several months off therapy and the virus did not rebound. So a quirk — of the mother's decision, or accident, in not following up with the baby — has actually led to a situation that turned out to be beneficial.

So that case was accidental. How will doctors know in the future when to stop drug treatment, and is that even ethical?

To just ... stop would not be ethical, and that's the reason why we're sponsoring a clinical trial that will begin sometime at the end of April [or] at the beginning of May, where we're taking a large number of babies ... born of mothers who are infected, [women] who have not received any [anti-HIV] treatment [during pregnancy] at all, and we're going to be treating those babies literally within 48 hours of birth with the full component of the treatment regimen. [We will be] assuming that they are infected, even though they might not be. And then we'll wait for a considerable period of time, and very carefully, in individual babies, stop therapy to see if the virus rebounds.

Give us some context. Just how big a problem is it — babies born HIV-positive?

In the United States, it's really not a big problem at all only because we have the [prenatal and postnatal] care for the mothers, and almost all mothers who are infected will be started on [antiretroviral drug] therapy. It will be extremely unlikely that the baby will be infected – not impossible but very, very unlikely. However, the situation in the developing world is somewhat different. [There] it's not uncommon that a mother will come into a clinic, in labor, ready to deliver, never having seen a health care provider, and not being on antiviral therapy. Those are the babies that are at the highest risk.

How promising are these findings? Well, it's quite promising because if it's the second one that we have documented now — and there probably will be others coming along — it really brings up a broader concept. If you have the possibility of truly curing babies at the time of birth, then the risk/benefit ratio of waiting until you document that they're infected ... that really changes the equation. Copyright 2019 NPR. To see more, visit https://www.npr.org.