Miami Herald - Tuesday, July 20, 2004
Fred Tasker, Miami Herald

BANGKOK, Thailand - With an effective AIDS vaccine a decade away, and no major new drugs making their debut, the most exciting scientific development is a new class of drugs that can protect women during sex.

Called microbicides, they're vaginal gels, creams or foams that contain drugs successfully employed against HIV in pill or injection form. While they are still being tested, they represent a new line of defense for women, who make up one of every four new diagnosed AIDS patients in the United States.

"Microbicides can be crucial tools as female-controlled options," said Dr. Zeda Rosenberg, director of the nonprofit International Partnership for Microbicides, created in 2002 to speed their advent.

The concept of microbicides has been around for years, but some early versions didn't work. Now, six new drugs are being or will be tested on 20,000 volunteers over the next three years. A successful microbicide is probably at least five years away, Rosenberg said.

"They're cheap, easy to use, and your partner can't tell," said Dr. Corklin Steinhart, senior attending physician at Mercy Hospital in Miami, who attended the XV International AIDS Conference in Bangkok. "Condoms are a real issue in much of the world. If a man knows his woman is using protection, it can be a real issue in their relationship."

During sex, women are much more vulnerable than men to contract HIV because of the vagina's larger surface area and the kinds of cells that make up its lining.

Studies also say men are less willing to use condoms with wives and girlfriends than with casual sex partners, she said.

"For women worldwide," Rosenberg said, "being young and married are the most significant risk factors for acquiring HIV."

But a computer modeling study by the London School of Hygiene and Tropical Medicine indicated that even a 60 percent effective microbicide introduced in 73 low-income countries and used by only 20 percent of women could avert 2.5 million HIV infections in three years, Rosenberg said.

Nearly five million people worldwide were newly infected with HIV in 2003.

A successful microbicide could kill the virus in the vagina or cervix; keep any cells that escape from attaching to a woman's cells; and stop the virus from replicating by blocking enzymes.

Some gels or creams might last 24 hours; microbicides from time-delivery intravaginal rings might give protection for a month or more.

But while a microbicide must kill the HIV virus, it's important that it not kill the vagina's natural bacteria or lower the acidity of the vagina, which also helps kill invading organisms.

At present, two candidate drugs are in full-scale trial, which usually take two to three years:

- Savvy, a gel by Biosyn Inc. of Pennsylvania, being tested on 2,200 women in Ghana and a group in Nigeria.

- Carraguard, being tested in South Africa by the Population Council.
040720
MH040718

AEGiS presents published material, reprinted with permission and neither endorses nor opposes any material. All information contained on this website, including information relating to health conditions, products, and treatments, is for informational purposes only. It is often presented in summary or aggregate form. It is not meant to be a substitute for the advice provided by your own physician or other medical professionals. Always discuss treatment options with a doctor who specializes in treating HIV.

Copyright ©1980, 2004. AEGiS. All materials appearing on AEGiS are protected by copyright as a collective work or compilation under U.S. copyright and other laws and are the property of AEGiS, or the party credited as the provider of the content. .