At the forthcoming Biennial Conference of the Irish Forum
for Global Health (IFGH) in Maynooth, Ireland, one of the two keynote guest
lectures - The John Kevany Memorial lecture - will be delivered by Dr Zeda
Rosenberg, Chief Executive Officer (CEO) of the International Partnership for
Microbicides (IPM) on "New Science, New Hope: Giving Women Power over
HIV/AIDS." The microbicides refer to a new type of product being developed
that people could use vaginally or rectally to protect themselves from HIV and
possibly other sexually transmitted infections.
One of the defining moments in microbicides advocacy was in
July 2010 at the XVIII International AIDS Conference (IAC) in Vienna, Austria
where successful results of the much awaited tenofovir microbicides clinical
trials (CAPRISA 004) were announced: women who used the tenofovir microbicide
gel were far less likely to become infected with HIV than women using a placebo
gel. The tenofovir microbicide gel users were 39 percent less likely, overall,
to become infected with HIV than women who received a placebo gel. More
importantly, underlining the significance of adherence and counselling in
clinical trials, women who used the tenofovir microbicide gel correctly more
than 80 percent of the time, HIV infection was 54 percent less likely. Also as
many advocates of new HIV prevention technologies demand - these tenofovir
microbicide also showed activity against genital herpes (a sexually transmitted
infection), reducing its incidence by half.
Let me put a word of caution here: this is undoubtedly
welcome news, but research is not over yet. There is still a long way to go
which may span over years through rigorous path of clinical trials and product
development, before any microbicide can truly be available to communities.
One of the big debates around using anti-retroviral (ARV)
based microbicides to prevent HIV transmission is that tenofovir is also used
by people living with HIV (PLHIV) for their ARV therapy. PLHIV take oral
version of tenofovir in ARVs like Viread, Truvada and Atripla.
So the worry is: will using this ARV based microbicide
(tenofovir in this case) make people resistant to tenofovir and thereby negate
the positive outcomes of ARV based therapy later in their lives in case they
become infected with HIV and require the ARV treatment?
"There is now evidence to indicate that ARVs can
prevent HIV as well as some of the non-HIV STIs. The major challenge facing the
Microbicides Society of India (MSI) as well as other partner research agencies
globally, would be to make a
combination of different ARVs, so that these products become more effective, safer and user friendly for preventing the
HIV and some of the non-HIV STIs as well as reproductive tract infections
(RTIs). It would be an icing on the cake, if few of these microbicidal products
could also provide the contraceptive protection concurrently to the users of
these products" said Dr Badri N Saxena, President, Microbicides Society of
India (MSI), who is a globally acclaimed researcher and an inspiring advocate
for new HIV and reproductive health technologies.
"One reason for engaging ARV drugs into microbicides
development is to accelerate the candidates that are ready to go into clinical
trials because they come from a very rich product development profile. So now
we have so many good candidates, can we provide the much needed bridge to
establish biological plausibility - to find out will these things actually work
in clinical trials" said Prof Robin Shattock to this correspondent at the
International Microbicides Conference in Pittsburgh, USA (May 2010).
Also at the International Microbicides Conference earlier
this year, two key studies were presented - one study involving a mathematical
model and the other assays of cells and tissue, and both these studies arrived
at the same answer to the worrying question whether drug resistance could be a
problem if ARV drugs become a mainstay for HIV prevention. Resistance could
happen, if people, who are unknowingly already infected with HIV, use the
approach. So in other words, if HIV negative people use ARV based microbicides
the risk of developing resistance is not there, but if they are already HIV
positive and unaware of their status, the risk of resistance is there. These
two studies underscore the importance of incorporating routine HIV testing and
ongoing monitoring of infection status in any prevention program that involves the
use of ARVs.
Probably the forthcoming Irish Forum for Global Health
(IFGH) biennial conference might offer some answers to these concerns and give
a major thrust to research and eventual development of new HIV prevention