A baby with the virus
that causes AIDS was given high doses of three antiretroviral drugs
within 30 hours of her birth. Doctors knew the mother was HIV positive
and administered the drugs in hopes of controlling the virus.
Two years later, there is no evidence of HIV in the child's blood.
The Mississippi girl is
the first child to be "functionally cured" of HIV, researchers announced
Sunday. They said they believe early intervention with the
antiretroviral drugs was key to the outcome.
A "functional cure" is
when the presence of the virus is so small, lifelong treatment is not
necessary and standard clinical tests cannot detect the virus in the
blood.
Scientists: Two-year-old 'cured' of HIV
HIV girl's 'cure' a breakthrough
'Huge' implications in HIV treatment
The finding was announced at the 2013 Conference on Retroviruses and Opportunistic Infections in Atlanta.
The unidentified girl was
born HIV positive to a mother who received no prenatal care and was not
diagnosed as HIV positive herself until just before delivery.
"We didn't have the
opportunity to treat the mom during the pregnancy as we would like to be
able do to prevent transmission to the baby," said Dr. Hannah Gay, a
pediatric HIV specialist at the University of Mississippi Medical
Center.
Gay told CNN the timing
of intervention -- before the baby's HIV diagnosis -- may deserve "more
emphasis than the particular drugs or number of drugs used."
"We are hoping that
future studies will show that very early institution of effective
therapy will result in this same outcome consistently," she said on the
eve of the Atlanta conference.
High-risk exposure
Dr. Katherine Luzuriaga,
an immunologist at the University of Massachusetts who worked closely
with Gay, called the developments fascinating, including the fact that
the toddler was found to have no virus in her blood even after her
mother stopped giving her treatment for eight to 10 months.
"This is the very first
case in which we've conclusively been able to document that the baby was
infected and then after a period of treatment has been able to go off
treatment without viral rebound," Luzuriaga told CNN.
Once it was determined
the Mississippi mother was HIV positive, Gay immediately began giving
the infant antiretroviral drugs upon the baby's delivery in an attempt
to control HIV infection.
"We started therapy as
early as possible, which in this case was about 30 hours of age," the
physician said. "And because it was a high-risk exposure, I decided to
use three drugs rather than one."
Within a couple of days, Gay confirmed the child was HIV positive. She said the baby had probably been infected in the womb.
The child remained on
antiretroviral drugs for about 15 months. Her mother then stopped
administering the drug for some reason, and care was resumed after
health officials intervened, Gay said.
Researchers have long
known that treating HIV-positive mothers early on is important, because
they pass antibodies on to their babies.
"One hundred percent of
(HIV-positive) moms will pass those antibodies, but in the absence of
treatment, only 30% of moms will transmit the actual virus," Luzuriaga
told CNN.
HIV-positive mothers given appropriate treatment pass the virus on in less than 2% of cases, Luzuriaga said.
"So all babies are born
antibody positive, but only a fraction of babies born to HIV-positive
women will actually get the virus, and that fraction depends on whether
the mom and baby are getting antiviral prophylaxis (preventative
treatment) or not," Luzuriaga said.
Newborns are considered
high-risk if their mothers' HIV infections are not under control or if
they are found to be HIV positive when they're close to delivering.
Moving quickly to suppress the virus
Usually, these infants
would get antiviral drugs at preventative doses for six weeks to prevent
infection, then start therapy if HIV is diagnosed.
Investigators said the
Mississippi case may change that practice because it highlights the
potential for cure with early standard antiretroviral therapy, or ART.
ART is a combination of at least three drugs used to suppress the virus and stop the progression of the disease.
But they do not kill the
virus. Tests showed the virus in the Mississippi baby's blood continued
to decrease and reached undetectable levels within 29 days of the
initial treatment.
Dr. Deborah Persaud, a
virologist with Johns Hopkins Children's Center, was lead author on the
report presented at the conference.
The early treatment likely led to the infant's cure, she said.
"Prompt antiviral
therapy in newborns that begins within days of exposure may help infants
clear the virus and achieve long-term remission without lifelong
treatment by preventing such viral hideouts from forming in the first
place," Persaud said.
Persaud and Luzuriaga
are part of a group of researchers working to explore and document
possible pediatric HIV cure cases. The group was funded by a grant from
amfAR, the Foundation for AIDS Research, and the National Institutes of
Health.
Dr. Rowena Johnston,
amfAR vice president and director of research, said it is "imperative
that we learn more about a newborn's immune system, how it differs from
an adults and what factors made it possible for the child to be cured."
Dr. Anthony Fauci,
director of the National Institute of Allergy and Infectious Diseases at
the National Institutes of Health, said he is enthusiastic about the
findings.
"The best way to either
eliminate the virus or allow the immune system to suppress residual
virus is to treat someone as early as possible after infection so as not
to allow a substantial reservoir of the virus to take hold," Fauci told
CNN.
"At the same time, you
prevent the immune system from being severely damaged by the continual
replication of (the) virus for an extended period of time," he said.
"The situation with a child born of an infected mother where most of the
infections are transmitted to the newborn at or around the time of
delivery provides an excellent opportunity to cure an infected baby, and
this approach deserves further study."
'Berlin patient'
Researchers say the only
other documented case of an HIV cure is that of Timothy Brown, known as
the "Berlin patient." In 2007, Brown, an HIV-positive American living
in Germany, was battling both leukemia and HIV when he underwent a bone
marrow transplant that cured not only his cancer but his HIV.
In an interview last year, Brown told Dr. Sanjay Gupta, CNN's chief medical correspondent, he was still HIV-free.
"I've been tested
everywhere possible," said Brown, who now lives in San Francisco. "My
blood's been tested by many, many agencies. I've had two colonoscopies
to test to see if they could find HIV in my colon, and they haven't been
able to find any."
But Brown's case is rare.
And the procedure, which
is extremely dangerous, won't work in most patients because the bone
marrow he received had a special genetic mutation that made the stem
cells in it naturally resistant to the virus.
Researchers tell CNN
only 1% of Caucasians -- mostly Northern Europeans -- and no
African-Americans or Asians have this particular mutation.
In June, five years after he was "cured," reports surfaced that "traces" of the virus had been found in Brown's blood.
Even then, some HIV
experts said that doesn't matter, that he's been cured. In fact, many
AIDS experts said they believe Brown has experienced what's called a
"sterilizing" cure, meaning the virus has been eliminated from the body
entirely.
Routine clinical testing on the Mississippi toddler continues, Gay said.
So far, there is no evidence of the virus.
"On the ultra-sensitive
testing, we are occasionally getting signals so we cannot say with
certainty that this child is absolutely clear of HIV, but we will
continue to follow up with the baby," Luzuriaga said.
"We have formed a
hypothesis and that is already driving the design of new studies and
clinical trials that will help us to answer the question of whether by
coming in very early we will be able to treat children for a while and
then remove them from therapy."
culled from www.cnn.com
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