http://www.redorbit.com/news/health/1636396/ experimental_hiv_protection_gel_shows_promise/

Salim Abdool Karim, a South African researcher who presented the results, said a multi-country study suggests a gel made by Massachusetts-based Indevus Pharmaceuticals Inc. cut HIV infection to a slight degree.

The PRO 2000 gel was found to have reduced the rate of HIV infection by a third.

However, additional studies have shown that men who take powerful HIV cocktails can still pass the virus on in their semen, even if it cannot be found in the blood.

"I would argue that it is infectious although we don't know what level of virus is required," said Prameet Sheth of the University of Toronto in Canada, and Anne-Genevieve Marcelin of the Pitie-Salpetriere in Paris.

While such drug cocktails do not cure AIDS, they are able to bury levels of the virus to so-called undetectable levels in blood. This helps stop the virus from destroying the immune system and keeps patients healthy.

Karim told an audience at the Conference on Retroviruses and Opportunistic Infections in Montreal that it was the first study that now shows a “promising candidate” for slowing the pandemic of deadly human immunodeficiency virus, which infects 33 million people globally and which has killed 25 million.

"We do not regard it as a definitive conclusion that PRO 2000 is a microbicide but we certainly view it as very promising," he said.

A separate microbicide called BufferGel made by ReProtect Inc was also tested, but researchers were unable to find any significant indication that it worked. The study was only designed to show the gels were safe, as other studies have shown would-be microbicides actually raised the risk of infection.

Some 3,100 women participated in the study. The women were divided into four groups: One-quarter of them used the Indevus gel, which is supposed to block the AIDS virus from attaching to certain white blood cells; Another quarter were put on a gel made by Baltimore-based ReProtect; and the rest were given a placebo gel, or no gel at all.

Those women who used the Indevus-made gel had a 30 percent lower rate of HIV infection than the other women in the study. However, the difference was not statistically significant, meaning the results could have occurred by chance.

"The study, while not conclusive, provides a glimmer of hope to millions of women at risk for HIV, especially young women in Africa," said Karim.

National Institute of Allergy and Infectious Diseases director Dr. Anthony S. Fauci said an effective microbicide would be a valuable tool that women could use to protect themselves against HIV and one that could substantially reduce the number of new HIV infections worldwide.

"Although more data are needed to conclusively determine whether PRO 2000 protects women from HIV infection, the results of this study are encouraging," he added.