A LARGE follow-up clinical trial to confirm the encouraging results last year of a small study that tested an antiretroviral-based microbicide gel which showed that it could reduce HIV infection in women by almost 40 percent is due to begin in a few weeks.

Dubbed the Facts 001 study, the clinical trial seeks to expand on the findings last year of an initial Phase III study, Caprisa 004, which investigated the concept of using a product for Aids treatment in HIV prevention.

Testing an antiretroviral drug known as Tenofovir in a microbicidal gel formulation among 900 women, where half received the actual study gel and the other a gel not containing Tenofovir, the study found that the product can reduce HIV infection by 39percent when used before and after sex. The research also went on to show - by sheer coincidence as the study was not meant for the purpose - that the Tenofovir gel can protect women from contracting herpes by about 51percent.

This Phase III study, under the guidance of three eminent women scientists, will be led by Professor Helen Rees of the Wits Reproductive Health and HIV Institute.

"Before Caprisa released their results, they summoned many of South Africa's best HIV prevention researchers to say: If Caprisa comes in positive, what should we do as a country because we know that the study was not decided for licensure?

"We need to confirm it. If there's a positive result we need to get into the field to confirm it," Rees says.

Already working on the knowledge that the Tenofovir gel is effective against HIV prevention and herpes, Rees says researchers are hoping that the result in the secondary study will be more significant. The finding could lead to the licensure of the Tenofovir gel as the first ever microbicide against HIV infection and herpes.

"The study objectives are to confirm the Caprisa 004 results in larger and more diverse populations. So, you need to also demonstrate that this gel is going to work in different sorts of populations where the HIV incidence is lower, which is the case in many parts of the country.

"We want to look at the effectiveness of the gel against HIV and, this time, we want to design the study to specifically also look at whether it's effective against herpes because the Caprisa study wasn't actually designed specifically to look at that," she says.

The Department of Science and Technology has thrown its weight behind the Facts 001 study. The United States government's agency for Aids, USAid, is also investing about R120 million into the study.

Researchers will start recruiting participants into the study as from early July. - Health-e News