A glimmer of hope for microbicide research
By IRIN (Durban, South Africa) 10 February 2009: After years of disappointments, AIDS researchers have announced results from a trial in which a vaginal microbicide appeared to offer promise in preventing HIV infection in women.
http://www.plusnews.org/Report.aspx?ReportId=82836
According to findings from a clinical trial involving more than
3,000 women in Malawi, South Africa, Zambia, Zimbabwe and the United
States, the microbicide PRO 2000 gel was 30 percent effective.
"This is the first time in the history of microbicide research that we
have found something that works, even if its 30 percent," Gita Ramjee,
principal investigator of the trials in South Africa, told journalists
on 9 February in the country's east coast port city of Durban.
Ramjee described the results as a "glimmer of hope" that the
microbicides concept could become an effective HIV prevention tool for
women.
Although the results were "promising" they are not statistically
significant, as there was a one-in-ten chance that the 30 percent
reduction in HIV infections seen in women who used PRO 2000, versus
those who used a placebo, was due to chance, Ramjee explained
Scientifically, results are not regarded as "significant" unless the
chance they are wrong is 0.05 percent or less than one in 20. "If we
had seen a 33 percent reduction it would have been statistically
significant," Ramjee said.
Women in the trial were randomly assigned to one of four groups: one
group involved women who received a 0.5 percent dosage of PRO 2000 gel;
in the second, women were treated with BufferGel, a second microbicide
candidate; and in the third and fourth groups women received a placebo
gel or no gel at all
The study, conducted by the US-based Microbicide Trials Network, also
found more regular gel use, corresponded to a higher level of HIV
protection.
According to Ramjee, PRO 2000 provided protection of up to 78 percent
against the virus in women who were not able to negotiate condom use,
but reported more frequent application of the gel. The study also
reported a higher level of adherence: participants in the three gel
groups reported using the gel 81 percent of the time.
Results from a larger study of PRO 2000 are expected later this year
and it is hoped it will be able to demonstrate efficacy if they find
similar reductions in the HIV infection rate.
Trial participant Desiree, who declined to use her last name, was not
sure of what to make of the hype surrounding the results of the
clinical trials.
"One on one side I am proud of what I did and I am quite glad there is
some progress, but I don't want to get too excited just in case it
doesn't work in the end," the 26-year old mother told
IRIN/PlusNews.
Desiree spent almost two years on the trial despite criticism and
negative reactions from community members who believed the trial was
"injecting people with AIDS".
"Some people felt because I was Indian I shouldn't do it, but I didn't
listen to them. But my mother was fine, she said 'OK no problem', and
my partner was also fine. We even enjoyed using the gel," she
said.
The South African arm of the trials was conducted in Durban's
traditionally conservative Indian township of Chatsworth, as well as
the rural district of Hlabisa in northern KwaZulu Natal.
Dr Samu Dube, the Africa Programme Leader for the Global Campaign for
Microbicides, has cautiously welcomed the findings.
"It is the first time we are seeing positive news on clinical trials
[of microbicides], it is a smiling moment. But we expect more. For us
to jump around, the results should be statistically significant. But we
will get there," she told IRIN/PlusNews.
The microbicide field has been desperate for positive news after a host
of depressing trial results, which included the 2007, clinical trials -
using a cellulose sulphate-based microbicide - which were terminated
after preliminary findings found higher HIV infections in the trial
group compared to the placebo group.
In 2008, the US-based reproductive health organisation, Population
Council announced that Carraguard - the first microbicide to complete
the advanced stage of clinical testing - had also failed to prevent HIV
infection.
In a statement, Lori Heise, director of the Global Campaign for
Microbicides (GCM), said PRO 2000 was "not a home run, but this proof
of concept should "invigorate the field."

