Doctors at the Mount Sinai School of Medicine have tested a gel that when applied topically in the vagina, may help prevent infection by both H.I.V. and herpes simplex virus.

The effectiveness of the gel, called PRO 2000 and made by Indevus Pharmaceuticals, was shown in a pilot study of 20 H.I.V.-infected women.

The study found that the gel significantly reduced virus levels while causing no inflammatory response, and a new study is under way to determine whether the gel causes any other side effects

A much larger study of  the gel has been financed and is to include more than 3,000 women.

Researchers have long sought such a treatment, and they want to be sure that “whatever drug makes it to the market will be safe.”

For the complete article, see http://query.nytimes.com/gst/fullpage.html?sec=health&res=9F00E3D71E3DF93BA35750C0A9639C8B63&scp=2&sq=herpes%20gel&st=cse.