VULINDLELA,
South Africa — With an AIDS vaccine still out of reach, two rigorous
new studies have found different ways to sharply cut H.I.V. infections among women
and schoolgirls, who make up a majority of the newly infected in sub-Saharan
Africa.
After
two decades in which researchers searched fruitlessly for an effective vaginal
microbicide to block H.I.V., South African scientists working in two AIDS-devastated
communities of South Africa, one
rural and one urban, say they have finally found something that shows real
promise.
Women
who used a vaginal microbicidal gel containing an antiretroviral medication
widely used to treat AIDS, tenofovir,
were 39 percent less likely over all to contract H.I.V. than those who used a
placebo. Those who used the gel most regularly reduced their chances of
infection 54 percent, according to a two-and-a-half year study of 889 women by Caprisa,
a Durban-based AIDS research center.
Broader
trials are needed to confirm the results, and it will most likely be years
before the product is publicly available, but if produced on a large scale the
gel would cost less than 25 cents per application, the lead investigators
estimated.
Because
the trial was relatively small and the gel was nowhere close to 100 percent
effective, AIDS scientists and public health officials wanted to see another
trial get similar results before they undertook the large fund-raising and
public education efforts that would be needed to make billions of doses of the
gel, as well as the applicators, which are more expensive, and then to persuade
women to use them and governments of poor countries to adopt them.
Dr.
Bruce Walker, a Harvard Medical School professor who was not involved in the
study, said a cheer erupted when researchers unveiled their findings to a small
group of scientists last month in Durban.
“This
is the first time that there’s been a tool that women can use to protect
themselves from becoming infected,” he said. “It’s a game changer.”
In
Vienna, where the meeting of the International AIDS Society just opened,
leaders of the global fight against AIDS said they found the results of the
microbicide trial very impressive. The study was
published online on Monday by Science magazine.
“This
is very encouraging,” said Michel Sidibé, executive director of Unaids, the United
Nations AIDS agency. “It can be controlled by women, and put in 12
hours earlier, and that is empowering. They do not have to ask the man for
permission to use it. And the cost of the gel is not high.”
In
another piece of progress against AIDS, a separate, large study in Malawi sponsored by the World Bank, and made public
on Sunday, found that if poor schoolgirls and their families received small
monthly cash payments, the girls had sex later, less often and with fewer
partners.
A
year and a half after the program started, the girls were less than half as
likely to be infected with the AIDS or herpes viruses than were girls whose families
got no payments. The likelihood that the girls would agree to sex in return for
gifts and cash declined as the size of the payments from the program rose,
suggesting the central role of extreme poverty in sexual choices.
“Maybe
we can combine these behavioral and biomedical interventions,” said Dr. Tim
Farley, a scientist with the World
Health Organization involved in H.I.V. prevention research. “We need
to pursue both avenues.”
At
a time of intensifying competition for global health dollars, when the number
of people who contract H.I.V. is outstripping those put on treatment each year,
pressure is mounting on African countries and donors to focus more heavily on
prevention. Male circumcision
is one method proven to at least halve a man’s chances of H.I.V. infection.
Scientists
say the success of the $18 million microbicide trial, largely paid for by the United States Agency for International Development,
and the study on cash payments offer hope to girls and women in Africa, who
have higher rates of H.I.V. infection than their male counterparts and often
less power in relationships to protect themselves.
There
have been other signs of progress. A new Unaids study found that H.I.V.
prevalence among young people had declined by more than 25 percent in 15 of the
21 countries most affected by AIDS. In eight countries, the agency found
evidence of positive changes in sexual behavior among young people, for example
delaying having sex, having fewer partners and the increasing use of condoms.
In
the $400,000 trial in Malawi, 3,800 teenage girls and young women, ages 13 to
22, were randomly assigned to two groups. Half the girls received no cash
payments. The parents of the other half were paid $4 to $10 a month while the
girls themselves received $1 to $5 a month if they attended school regularly.
After
18 months, the H.I.V. prevalence among the girls who got the cash was 1.2
percent, compared with 3 percent for the others. “The program empowered these
girls to make better choices,” said Berk Ozler, a senior economist with the World Bank’s
Development Research Group.
While
cash programs are
already spreading in Africa, the antiretroviral gel will take longer, according
to the husband-and-wife team of epidemiologists who led the study. They are Dr.
Salim S. Abdool Karim, Caprisa’s director, and Dr. Quarraisha Abdool Karim,
associate scientific director.
“I
would be very sad if we had to sit around a table three years from now and we
don’t have the confirmation and regulations in place,” Dr. Salim Karim said.
Dr.
Quarraisha Karim noted that, “For women, it certainly is a turning point.”
In
South
Africa, where 5.7 million people are H.I.V.-positive, more than in
any other nation, the government is eager to move forward. “As soon as we’re
confident it’s a safe and effective product, we should do our best to get it
out,” said Derek Hanekom, the country’s deputy minister of science and technology.
The
women who participated in the study — in the city of Durban and in the rural
community of Vulindlela, in the rolling hills of KwaZulu-Natal — used the gel
up to 12 hours before and after sex. Usually their partners were not aware of
it. Tissue biopsies found levels of tenofovir that were 1,000 times what they
would have been in the blood if the drug had been taken by pill, the team said.
The
success follows years of disappointing results in trials of other microbicides
that were found to be ineffective, or even to raise a woman’s risk of H.I.V.
infection. There are currently other trials under way that use tenofovir in gel
and pill forms.
Gilead Sciences,
the California-based biopharmaceutical company that developed tenofovir,
donated 65 pounds of the active ingredient for the study. It has also
relinquished any claim to royalties on the gel if it is distributed in Africa
and poor countries in other parts of the world.
Dr.
Howard Jaffe, president of the Gilead Foundation, the company’s charitable arm,
said that Dr. Salim Karim — nicknamed Slim — pitched the microbicide idea to
company scientists in 2004, to initial reluctance.
“Slim
is nothing if not charismatic, passionate and intelligent, and we thought it needs
to be studied, it will be studied and this may be the best time to do it,” Dr.
Jaffe said.
In
Vulindlela, women have a desperate need for a way to protect themselves. H.I.V.
testing of pregnant women in the area has found that one in 10 is already H.I.V.-positive
by 16; half are infected by 24.
Before
antiretroviral treatment became available here, the graveyards were crowded
every weekend with funeralgoers. Fewer people are dying now, but many young
women are still getting infected.
Xoliswa
Mthethwa, 26, who was part of the study, said she told her boyfriend about the
gel and he was very supportive. If it worked, she said, “I’d be the first
person to go buy it.”