Tuesday March 2 11:40 AM ET
Promising AIDS Preventative May Put Women In Control
By Eric Onstad
THE HAGUE, Netherlands (Reuters) - A range of invisible, odorless substances holds the prospect of putting women --
especially in Africa -- in control of preventing AIDS.
But microbicides are not getting the major research push they deserve because drug firms see little chance of making big profits,
experts say.
Scientists have been trying for about 12 years to develop an inexpensive gel or cream to go in the vagina before sex that would
kill any infection by the HIV virus that causes AIDS.
''We all realize that this would be the next important advance,'' Nicholas Dodd, head of the technical branch of the United
Nations Population Fund, said.
''These would give a way for women themselves to have control over preventing AIDS infections because of course with
condoms they have to depend on men,'' he told Reuters at a population review conference in The Hague.
The conference, which studied progress since a landmark population meeting in Cairo in 1994, called for more funding for
microbicide research.
Finding a microbicide that works has gained extra urgency over the last few years as the number of infected women soars. Last
year 70 percent of the 5.8 million new AIDS infections occurred in sub-Saharan Africa and young women there have the
fastest infection rate.
''In some of the worst affected countries, HIV-infected women outnumber infected men by as much as 16 to one in the
younger age groups,'' the joint United Nations project UNAIDS said in a recent report.
RESEARCH LAGS, PRODUCT SEEN TOO RISKY
Microbicides are at the very least five years from coming onto the market even if current trials prove positive. With female
condoms too costly for most women in poor countries, more resources are needed to speed the process, officials say.
But major pharmaceutical firms, which can pour huge amounts of money into research of new drugs, have shown little interest in
developing such a product. One reason is a spate of lawsuits, especially in the United States, regarding contraceptives or
related products.
''The companies shy away from liability in product development,'' said UNAIDS microbicides expert Joseph Perriens. ''Also
they have the perspective that 90 percent of the market for this kind of product is perceived in developing countries where
there is no buying power. I think those perceptions are mistaken,'' he added.
Another issue for drug firms is that most of the potential products use substances on which patents have lapsed, so the profit
margins would be skimpy. With big drug companies out of the picture, the initiative has fallen to governments, private
organizations and small biotechnology firms.
Some 20 microbicide products are in some stage of development, but two are farthest along, Perriens said.
One is from the New York-based Population Council, which has a long history of developing new contraceptives. Their
product, code named PC512, is soon due to start clinical human trials in South Africa and possibly Thailand.
It is a gel that uses a byproduct of seaweed and nonoxynol-9, which has been used for years as a spermicide, said George
Brown, vice president of international programs. ''It has been shown to be very promising in a series of lab studies and very
soft studies in humans,'' he added.
CHEAP AND EASY
The product would be cheap and easy to use. ''One of our goals is to get a product that would be sufficiently low cost so that
most if not all African and other women around the world could have access,'' Brown said.
U.S. firm Procept Inc (Nasdaq:PRCT - news), based in Cambridge, Massachusetts, is also due to launch human trials this year
in the United States and South Africa for its product, PRO 2000 Gel.
The National Institutes of Health, one of two U.S. agencies spending $25 million per year since 1996 on microbicide research,
is sponsoring the clinical trial.
The first microbicide products used nonoxonyl-9 alone but that was shown to irritate the walls of the vagina and actually allow
easier infection.
The answer to an effective microbicide may lie in using a cocktail of substances, said Perriens, who previously worked at
developing drugs.
''The weakness of all the current microbicides designs is they have a sole mechanism of action,'' he said. ''It is my opinion that
to have a very effective microbicide you will probably have to combine several active ingredients so you have a multi-step
inhibition of HIV entry into the body.'' |
