December 2011, Week 5


Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Portside Moderator <[log in to unmask]>
Reply To:
Sat, 31 Dec 2011 01:03:22 -0500
text/plain (154 lines)
Breakthrough of the Year
HIV Treatment as Prevention

Jon Cohen
Science 23 December 2011:
Vol. 334 no. 6063 p. 1628
DOI: 10.1126/science.334.6063.1628

     Science has chosen the finding that antiretroviral
     drugs reduce the risk of heterosexual transmission
     of HIV as its Breakthrough of the Year.

On 1 December, George Washington University in
Washington, D.C., hosted "The Beginning of the End of
AIDS," a splashy World AIDS Day event that featured
three U.S. presidents, business magnates, and rock
stars. The catalyst that brought them together was
something Anthony Fauci, the top U.S. government
HIV/AIDS scientist, told the crowd even 1 year ago would
have seemed "wishful thinking": a clinical trial dubbed
HPTN 052 and its "astounding" result.

HIV/AIDS researchers have long debated whether
antiretroviral drugs (ARVs) used to treat HIV-infected
people might have a double benefit and cut transmission
rates. To some it was obvious: ARVs reduce HIV levels,
so individuals should be less infectious. Skeptics
contended that this was unproven. Indeed, a consensus
statement issued by the Swiss Federal Commission for
HIV/AIDS in 2008 that said effective ARV treatment could
virtually stop heterosexual transmission was denounced
as "appalling," "inconclusive and irresponsible,"
"dangerous," and "misleading." The Joint United Nations
Programme on HIV/AIDS and the World Health Organization
also responded with alarm, urging people to continue
using condoms and stressing that semen or vaginal
secretions might harbor the virus even when blood tests
showed no trace of it. "More research is needed to
determine the degree to which the viral load in blood
predicts the risk of HIV transmission," they cautioned.

Then in May of this year, the 052 clinical trial
conducted by the HIV Prevention Trials Network reported
that ARVs reduced the risk of heterosexual transmission
by 96%. "Now we have absolute, confirmed data," said
Fauci at an AIDS conference this summer in Rome where
researchers first presented the HPTN 052 data in detail.
Fauci, who heads the U.S. National Institute of Allergy
and Infectious Diseases-the main funder of the $73
million trial-said the challenge now was to apply the
results. "We just need to take that data and run with
it," he said. "The idea of the tension between treatment
and prevention, we should just forget about it and just
put it behind us, because treatment is prevention."
Because of HPTN 052's profound implications for the
future response to the AIDS epidemic, Science has chosen
it as its Breakthrough of the Year.

Myron Cohen, an HIV/AIDS researcher at the University of
North Carolina, Chapel Hill, who heads the ongoing HPTN
052 trial, said the finding's impact surprised him.
"People were interested in the idea of treatment as
prevention, but it created a hurricane-force wind behind
the strategy," Cohen says. "The result was so

As Cohen and colleagues explained in the 11 August New
England Journal of Medicine, HPTN 052 enrolled 1763
"discordant" couples in which one person at the study's
start had a known HIV infection. The infected partner
could not be taking ARVs and had to have between 350 and
550 CD4 cells per milliliter, which indicates that the
person had some immune damage but had yet to develop
AIDS (defined as fewer than 200 CD4s). Five countries in
sub-Saharan Africa participated, as did Brazil, India,
Thailand, and the United States. The study randomly
assigned half the infected people to start ARVs
immediately, while the other half delayed treatment
until CD4 counts dropped below 250.

The researchers planned to compare the groups until
2015. But on 28 April, an independent monitoring board
that periodically reviewed the data stunned Cohen and
his collaborators when it recommended that the results
of the trial be made public as soon as possible. Of the
28 people who become infected with HIV that genetically
matched the viruses in their long-term partners, only
one was in the early treatment group-which also
experienced 41% fewer serious health problems associated
with HIV. Infected people in the delayed arm of the
study were offered ARVs immediately.

The HPTN 052 results and other recent successes have
raised hopes that combining such interventions can now
end AIDS epidemics in entire countries, if not the
world. ARVs are not a vaccine: People must take them for
decades, which is difficult to do and costly. But many
call HPTN 052 a "game changer" because of its near 100%
efficacy. "It has had an impact on our vision for the
future," says Françoise Barré-Sinoussi, a virologist at
the Pasteur Institute in Paris who shared the Nobel
Prize for helping to discover HIV. Researchers must
continue-and even intensify-efforts to develop an
effective AIDS vaccine and cure, Barré-Sinoussi
stresses, but she notes that countries can apply
treatment as prevention today.

Julio Montaner, a prominent advocate of the strategy at
the University of British Columbia, Vancouver, in Canada
says HPTN 052 has persuaded leaders such as U.S.
President Barack Obama-whose administration recently
announced a policy goal of creating "an AIDS-free
generation"-to take action. "Clinicians and policymakers
are always asking for the ultimate evidence," Montaner
says. "HPTN 052 was the unequivocal piece of the puzzle
to close any doubts."

Given resource constraints and logistical hurdles,
treatment as prevention isn't going to sweep the world
anytime soon. But HPTN 052 has made imaginations race
about the whatifs like never before, spotlighting the
scientifically probable rather than the possible. And
now a growing number of HIV/AIDS experts are insisting
that the irresponsible and appalling thing to do is


M. S. Cohen et al., "Prevention of HIV-1 Infection with
Early Antiretroviral Therapy," N. Engl. J. Med. 365,
493-505 (2011).

J. Cohen, "Halting HIV/AIDS Epidemics," Science 334,
1338-1340 (2011).


Portside aims to provide material of interest to people
on the left that will help them to interpret the world
and to change it.

Submit via email: [log in to unmask]

Submit via the Web: http://portside.org/submittous3

Frequently asked questions: http://portside.org/faq

Sub/Unsub: http://portside.org/subscribe-and-unsubscribe

Search Portside archives: http://portside.org/archive

Contribute to Portside: https://portside.org/donate