Big firms seek gel to ward off HIV

Two big American drug companies have signed agreements to develop a treatment called a microbicide - a gel or cream that a woman could use to protect herself from HIV.

Merck & Co and Bristol-Myers Squibb have signed separate licence agreements with the International Partnership for Microbicides (IPM) to develop such a product, long sought by doctors as a way for women and some men to prevent infection.

Many compounds are in development but all are experimental and this is the first time a large drug company has signed on to help make one.

"The search for an effective microbicide is crucial to providing women with more options to protect themselves against HIV infection," said Dr Peter Piot, executive director of the United Nations Aids organisation UNAids.

"Worldwide, nearly half of all [HIV] infections are in women," Dr Zeda Rosenberg, chief executive of IPM, told reporters in a telephone briefing.

In sub-Saharan Africa, the region by far the worst hit by Aids, half of all people infected with the Aids virus were women and young girls, she said.

"Existing HIV prevention strategies include sexual abstinence and the use of male and female condoms."

But Rosenberg said many women were infected by husbands or through forced sex, and few had the power to demand the use of a condom.

More than 39 million people, most of them in Africa, are infected with the HIV virus that causes Aids. More than 25 million have died. There is no cure.

While a vaccine is being developed, which is expected to take decades, prevention is the best way to fight Aids.

So groups such as IPM have been lobbying for the development of a microbicide, but funding has been limited so far.

Merck and Bristol are separately licensing to IPM the rights to develop a new class of drugs called entry inhibitors to develop into a microbicide.

Dr Helene Gayle, who heads Aids, tuberculosis and malaria funding for the Bill and Melinda Gates Foundation, said earlier versions of microbicides were very nonspecific.

"This second generation of microbicides are much more specific."

Only one potential microbicide has been tested in large groups of people - the spermicide nonoxynol-9. But researchers found that it failed to protect women, and in heavy users such as prostitutes, it raised the risk of infection.

Merck and Bristol have licensed their experimental drugs to IPM without royalties - payments usually taken by a drug's developer if it licenses a proprietary compound.

Merck's CMPD 167 and Bristol-Myers Squibb's BMS-378806 can protect monkeys from infection with a virus similar to HIV.

A study published in the journal Nature this week by Dr John Moore, of the Weill Medical College of Cornell University, and Dr Ronald Veazey, of the Tulane National Primate Research Centre, found that eight of 14 monkeys were protected from SHIV if treated with a microbicide two to six hours before being given the virus.

- REUTERS

Aids protection

* Women have often been advised to abstain from sex or make their partner use a condom, but many feel powerless to do either.
* A vaccine against HIV could be decades away.
* In the meantime, drug companies have been trying to develop a gel or cream to fight the virus.