Doctors announced on Sunday that a baby had been cured of an
H.I.V.
infection for the first time, a startling development that could change
how infected newborns are treated and sharply reduce the number of
children living with the virus that causes AIDS.
The baby, born in rural Mississippi, was treated
aggressively with antiretroviral drugs starting around 30 hours after birth,
something that is not usually done. If further study shows this works in other
babies, it will almost certainly be recommended globally. The United Nations
estimates that 330,000 babies were newly infected in 2011, the most recent year
for which there is data, and that more than three million children globally are
living with H.I.V.
If the report is confirmed, the child born in Mississippi
would be only the second well-documented case of a cure in the world. That
could give a lift to research aimed at a cure, something that only a few years
ago was thought to be virtually impossible, though some experts said the
findings in the baby would probably not be relevant to adults.
The first person cured was Timothy Brown, known as the
Berlin patient, a middle-aged man with leukemia who received a bone-marrow
transplant from a donor genetically resistant to H.I.V. infection.
“For pediatrics, this is our Timothy Brown,” said Dr.
Deborah Persaud, associate professor at the Johns Hopkins Children’s Center and
lead author of the report on the baby. “It’s proof of principle that we can
cure H.I.V. infection if we can replicate this case.”
Dr. Persaud and other researchers spoke in advance of a
presentation of the findings on Monday at the Conference on Retroviruses and
Opportunistic Infections in Atlanta. The results have not yet been published in
a peer-reviewed medical journal.
Some outside experts, who have not yet heard all the
details, said they needed convincing that the baby had truly been infected. If
not, this would be a case of prevention, something already done for babies born
to infected mothers.
“The one uncertainty is really definitive evidence that
the child was indeed infected,” said Dr. Daniel R. Kuritzkes, chief of
infectious diseases at Brigham and Women’s Hospital in Boston.
Dr. Persaud and some other outside scientists said they
were certain the baby — whose name and gender were not disclosed — had been
infected. There were five positive tests in the baby’s first month of life —
four for viral RNA and one for DNA. And once the treatment started, the virus
levels in the baby’s blood declined in the pattern characteristic of infected
patients.
Dr. Persaud said there was also little doubt that the
child experienced what she called a “functional cure.” Now 2 1/2, the child has
been off drugs for a year with no sign of functioning virus.
The mother arrived at a rural hospital in the fall of
2010 already in labor and gave birth prematurely. She had not seen a doctor
during the pregnancy and did not know she had H.I.V. When a test showed the
mother might be infected, the hospital transferred the baby to the University
of Mississippi Medical Center, where it arrived at about 30 hours old.
Dr. Hannah B. Gay, an associate professor of pediatrics,
ordered two blood draws an hour apart to test for the presence of the virus’
RNA and DNA.
The tests found a level of virus at about 20,000 copies
per milliliter, fairly low for a baby. But since tests so early in life were
positive, it suggests the infection occurred in the womb rather than during
delivery, Dr. Gay said.
Typically a newborn with an infected mother would be
given one or two drugs as a prophylactic measure. But Dr. Gay said that based
on her experience, she almost immediately used a three-drug regimen aimed at
treatment, not prophylaxis, not even waiting for the test results confirming
infection.
Virus levels rapidly declined with treatment and were
undetectable by the time the baby was a month old. That remained the case until
the baby was 18 months old, after which the mother stopped coming to the
hospital and stopped giving the drugs.
When the mother and child returned five months later, Dr.
Gay expected to see high viral loads in the baby. But the tests were negative.
Suspecting a laboratory error, she ordered more tests.
“To my greater surprise, all of these came back negative,” Dr. Gay said.
Dr. Gay contacted Dr. Katherine Luzuriaga, an
immunologist at the University of Massachusetts, who was working with Dr.
Persaud and others on a project to document possible pediatric cures. The
researchers, sponsored by amfAR, the Foundation for AIDS Research, put the baby
through a battery of sophisticated tests. They found tiny amounts of some viral
genetic material but no virus able to replicate, even lying dormant in
so-called reservoirs in the body.
There have been scattered cases reported in the past,
including one in The New England Journal of Medicine in 1995, of babies
clearing the virus, even without treatment.
Those reports were greeted skeptically, particularly
since testing methods were not very sophisticated back then. But those reports
and this new one could suggest there is something different about babies’
immune systems, said Dr. Joseph McCune of the University of California, San
Francisco.
One hypothesis is that the drugs killed off the virus
before it could establish a hidden reservoir in the baby. One reason people
cannot be cured now is that the virus hides in a dormant state, out of reach of
existing drugs. When drug therapy is stopped, the virus can emerge from hiding.
“That goes along with the concept that, if you treat
before the virus has had an opportunity to establish a large reservoir and
before it can destroy the immune system, there’s a chance you can withdraw
therapy and have no virus,” said Dr. Anthony S. Fauci, the director of the
National Institute for Allergy and Infectious Diseases. Adults, however,
typically do not know they are infected right as it happens, he said.
Dr. Steven Deeks, professor of medicine at the University
of California, San Francisco, said if the reservoir never established itself,
then he would not call it a true cure, though this was somewhat a matter of
semantics. “Was there enough time for a latent reservoir, the true barrier to
cure, to establish itself?” he said.
Still, he and others said, the results could lead to a
new protocol for quickly testing and treating infants.
In the United States, transmission from mother to child
is rare — several experts said there are only about 200 cases a year or even
fewer — because infected mothers are generally treated during their pregnancies.
If the mother has been treated during pregnancy, babies
are typically given six weeks of prophylactic treatment with one drug, AZT,
while being tested for infection. In cases like the Mississippi one, where the
mother was not treated during pregnancy, standards have been changing, but
typically two drugs are used.
But women in many developing countries are less likely to
be treated during pregnancy. And in South Africa and other African countries
that lack sophisticated testing, babies born to infected mothers are often not
tested until after six weeks, said Dr. Yvonne Bryson, chief of global pediatric
infectious disease at the University of California, Los Angeles.
Dr. Bryson, who was not involved in the Mississippi work,
said she was certain the baby had been infected and called the finding “one of
the most exciting things I’ve heard in a long time.”
Studies are being planned to see if early testing and
aggressive treatment can work for other babies. While the bone marrow
transplant that cured Mr. Brown is an arduous and life-threatening procedure,
the Mississippi treatment is not and could become a new standard of care.
While it might be difficult for some poorer countries to
do, treating for only a year or two would be cost effective, “sparing the kid a
lifetime of antiretroviral therapy,” said Rowena Johnston, director of research
at amfAR.
