A French teenager infected at birth with HIV has shown the
ability to control levels of the infection in her body -- without being on
antiretroviral treatment.
The finding
provides new hope that a "functional" cure for HIV -- where the virus
is brought down to low levels but not eradicated in the body -- may one day be
possible.
The 18-year-old
female, whose mother was HIV positive, was given antiretroviral treatment soon
after birth but stopped at age six and has since maintained undetectable levels
of the virus in her blood -- known as remission -- for 12 years.
"This is
the first [time] long-term remission has been shown in children, or
adolescents," said Asier Saez Cirion from the Institut Pasteur in France,
who presented the findings at the 8th
IAS conference on HIV pathogenesis, treatment and prevention, in
Vancouver this week.
Treatment
at birth
The researchers believe there may be
something unique in her biology that, combined with early treatment, enabled
her to control the infection. But for now, the reason remains a mystery.
She was
initially treated with antiretroviral drugs as a prophylactic to prevent
infection, and then given a combination of four antiretroviral drugs when the
virus was found to persist. She was monitored as part of a group of child HIV
patients, but failed to go in for observations between the age of five and six,
during which time her family chose to stop her treatment.
On returning for
check-ups one year later, medical teams found undetectable levels of HIV in her
blood despite her break from treatment.
More than 12
years later, the virus remains undetectable.
Learning from adults
"We have already found it was
possible in adults," said Saez-Ciron. This work follows on from his
previous research, in which 14 adults with HIV in France -- known as the "Visconti patients" -- were treated
for HIV soon after infection but stopped taking their drugs three years later
and showed no resurgence in the amount of virus found in their blood. The group
are considered to be post-treatment controllers of the virus.
Today, 12 remain
in control of their infection and without drugs, and they have an average of 10
years in remission.
What these
adults have in common with the French teenager is the early initiation of
antiretroviral treatment, thought to aid remission by preventing the formation
of HIV reservoirs inside the body.
"Again,
treatment was initiated very close to the period of infection," said
Saez-Ciron.
However, in
practice, most adults infected with HIV aren't diagnosed until the virus has
taken hold -- making early treatment a challenge. But children at risk of
infection from their mothers can be identified -- and treated — during
pregnancy, or at birth.
But pediatric
experts warn this kind of remission is not common.
A rare exception?
"This case is very rare," said
Deborah Persaud, a virologist at Johns Hopkins Children's Center in Baltimore, who worked on the case
of the "Mississippi baby," an infant once believed to have been
functionally cured of HIV as a result of immediate treatment with
antiretrovirals. No virus was detected for more than two years, before it again
showed up in tests.
Persaud is
excited that remission has been achieved for this length of time in the
teenager, but warns it is unlikely to be replicated easily. "Many kids
have gone off treatment -- and treated that early -- and we haven't seen this
outcome," she said. "Parents should not take their child of their
antiretroviral regimen to see if they're like this child."
The team at the
Pasteur Institute agrees.
"The fact
that you initiate treatment very early doesn't imply you will achieve remission
of infection," said Saez-Ciron.
The search for a reason
The team are now exploring the biology
behind this ability to control infection in hope of identifying key factors --
or markers -- in the body that could predict the possibility of remission, and
ideally a functional cure, in others. It's hoped this form of "cure"
would result in virus levels being so low, they no longer do enough damage to
the immune system to cause adverse health consequences.
"Most
people are not going to be able to control after treatment interruption, but
some can," said Saez-Ciron. "What we are trying to do now is
understand why some can and most do not." That could help develop
strategies to aid this type of remission in others.
Nobel laureate
Francoise Barre-Sinoussi, who co-discovered HIV in 1983, and works at the
Institut Pasteur, said: "We are learning from this patient, that's why
it's so exciting.
"We are
learning clearly which kind of response the strategy for the future should use.
This is critical if we want to make progress in the field of remission in the
future."
Saez-Ciron also
presented the results at the 2015 Towards an HIV Cure symposium, held
at the beginning of the conference, in which HIV cure researchers gathered from
around the world to hear the latest news in the field.
The announcement
of the case of the French teenager was met with restrained excitement, but also
a desire for more examples of this kind of functional cure.
"Being free
of viral rebound is impressive," said Anthony Fauci, head of the U.S. National
Institute of Allergy and Infectious Diseases (NIAID), who spoke at the
conference."But it's only one case ... as time goes by you [need to]
accumulate more evidence."
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