New vaginal gel shows promise in AIDS fight graphs (Roundup)

Feb 9, 2009, 22:56 GMT

Washington - A vaginal gel which can kill the HIV virus during sexual intercourse was hailed Monday for holding hope as another weapon in the arsenal against the deadly disease.

The gel, PRO2000, was 30 per cent effective in reducing the incidence of AIDS during more than three years of trials in Africa and the United States, according to research revealed at an AIDS conference in Montreal.

The substance, produced by Indevus Pharmaceuticals in Lexington, Massachusetts, contained a microbicide designed to kill the virus before it enters the body through the vagina or rectum.

In the test, women were divided into four groups. One group was given the PRO2000 gel and condoms, to be used as the women saw fit.

A second group received a fake gel and condoms, and a third group received just condoms. A fourth group received a second substance being tested called BufferGel.

After about 20 months, the women in the PRO2000 group had a 30 per cent lower HIV infection rate than the women in the other three groups.

'After working for over a decade in microbicide research, we are seeing a glimmer of hope of finding a safe and effective microbicide which could protect women and substantially reduce new HIV infections here in South Africa and globally,' said Gita Ramjee, director of the HIV prevention research unit of the South African Medical Research Council which oversaw the PRO2000 gel testing in South Africa.

Ramjee's statement appeared on the council's website.

The council said a microbicide gel would help women because they could initiate the protection in 'situations where it is difficult or impossible for women to negotiate condom use with their male partners.'

Lori Heise of the Washington-based advocacy group, Global Campaign for Microbicides, told Deutsche Presse-Agentur dpa, 'We think it's quite exciting.'

She was not directly involved in producing or testing the substance.

'What we have lacked in this field is what scientists call proof of concept,' she said. 'This trial clearly demonstrates that we can reduce risk through a vaginal product.'

The tests on PRO2000 were carried out on 3,000 women by the Microbicide Trials Network and funded by the National Institutes of Health. Test subjects lived in South Afria, Malawi, Zambia, Zimbabwe and the United States.

Nearly 30 years into the epidemic, an estimated 33.2 million people are believed to be infected with AIDS, according to the United Nation AIDS programme - a number that keeps growing.

A vaccine has proven elusive because the Human Immunodeficiency Virus (HIV) keeps changing its outer coat while destroying the immune system. It's difficult to create antibodies against such a formidable foe, scientists say.

The traditional approach to vaccines - using the live virus to induce antibodies but not cause the illness - doesn't work with HIV, and in some cases, has even produced a live virus in the body.

Drug therapy has become a little cheaper and more accessible, but is still very expensive.

Stepping into the lurch with increasing promise is the field of topical microbicide gels, women's advocates say. The wealthy Rockefeller and Bill and Melinda Gates foundations poured start-up money into microbicide research groups several years ago to pursue the idea.

Because the test group of 3,000 was not considered statistically significant, researchers were awaiting the results in November of another test series on PRO2000 being conducted by the British Microbicides Development Programme, Heise said.