A South African boy, believed to have been infected with HIV around
the time of his birth, has remained free of the virus for 8½ years after
early treatment — renewing hope among scientists that such outliers may
hold clues to help end the decades-old epidemic.
The case study, described by researchers before a presentation Monday
at an international AIDS conference in Paris, suggests a paradigm shift
in the treatment of those infected. It establishes that HIV may be
controllable in some way other than a daily and lifelong regimen of
antiretroviral drugs.
“This is really the first step toward HIV remission and a cure,” said
Deborah Persaud, a virologist at Johns Hopkins Children’s Center in
Baltimore. “Understanding the factors that came into play to lead to
this outcome is really going to inform science.”
Out of the millions of children worldwide who are HIV-positive, the
boy, now 9, is one of only three who have been identified by scientists
as having the ability to stop the virus from resurging for an extended
period of time.
Anthony Fauci, head of the National Institute of Allergy and
Infectious Diseases, struck notes of both optimism and caution when
speaking about him. Fauci described the child as being in “remission”
rather than being cured. And while hoping the boy would never have an
active infection in his lifetime, Fauci noted that HIV tends to hide in
“funny places” and that it is “not entirely inconceivable” a small
amount of the virus may remain in his body and start replicating again.
It is exciting to see this. It is encouraging to see a child going
for such a long period of time without rebounding,” Fauci said. “But we
don’t have the full answers to what this means yet.”
The first case of extended remission in a child was announced to
great excitement in 2013. Startled researchers reported that a girl —
who came to be known as the Mississippi baby — appeared to be
“functionally cured” 23 months after stopping treatment. The celebration
was premature, however: The virus returned shortly after that
announcement, and the young girl had to be put back on medications. But
her case brought to light the possibility of viral suppression in
children and led to the funding of other research into the phenomenon.
The second case, reported in 2015, involved a French teen who
underwent treatment from soon after birth to age 6 and whose blood
continued to have undetectable levels of the virus for 12 years after
stopping the drugs.
The South African boy came to the attention of researchers in 2008
through a larger study funded by the National Institutes of Health. It
took place from 2005 to 2011 at hospitals near Johannesburg and Cape
Town and involved nearly 400 HIV-positive babies.
Mark Cotton, a pediatric AIDS expert and one of the lead authors of
the paper being presented Monday in Paris, explained that children were
randomly put in one of three groups. One received the standard of care
at the time, which was to start therapy only when the individual showed
signs of becoming sick or evidence of a weakened immune system. The
other two groups started treatment immediately after their HIV-positive
status was confirmed, and stopped after 40 weeks or 96 weeks,
respectively. The goal was to figure out whether early treatment was
better than deferred treatment.
Cotton said the data appeared to show that children who had the virus
rebound earlier had to go back on medication after a couple of weeks.
But there was a huge surprise for subjects whose remission lasted
longer, he said, with several children not needing to return for two or
more years after 96 weeks of treatment.
For the 40-week treatment group, the average remission period was
about 30 weeks; for the 96-week treatment group, it was about 70 weeks —
although researchers caution that the results are still being analyzed
and should be taken as very preliminary.
Yet the one boy is already considered a distinct outlier. Born to an
HIV-positive mother, he was taken to one of the clinics in the study
when he was about 8 weeks old. He began therapy when he had a relatively
low viral load, and he took liquid antiretrovirals twice a day until he
was about 48 weeks of age. By the time he was done treatment just
before his first birthday, the viral load was undetectable, and year
after year during follow-up visits, he continued to show no signs of an
actively replicating virus.
One of the leading theories about how children in the study who had
the longest remission might be different has to do with how their immune
systems give them the power to suppress any rebound. Another factor may
be that their very early treatment did not give the virus a chance to
fully establish itself.
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