A Molecular "Condom" Against AIDS
While they are certainly better than nothing, traditional latex condoms do an imperfect job of preventing both pregnancy and sexually-transmitted diseases such as HIV and AIDS. Now scientists have designed an experimental "molecular condom" that could, some day, give women a much more reliable and practical way to prevent AIDS.
The new "molecular condom" comes in the form of a vaginally-inserted liquid that would form a gel-like coating and then, upon exposure to semen, return to liquid form and release an antiviral drug.
"It is composed of molecules that are liquid at room temperature and, when applied in the vagina, will spread and turn into a gel and effectively coat the tissue," says Patrick Kiser, an assistant professor of bioengineering at the University of Utah. "It's a smart molecular condom because we designed this gel to release anti-HIV drugs when the gel comes into contact with semen during intercourse."
"The ultimate hope for this technology is to protect women and their unborn or nursing children from the AIDS virus," but the molecular condom is five years away from tests in humans and roughly 10 years until it might be in widespread use, Kiser says.
Kiser and colleagues report development of the molecular condom in a study published online, Dec. 11, 2006, in the Journal of Pharmaceutical Sciences.
The molecular condom is part of a worldwide research effort to develop "microbicides" — drug-delivery systems such as gels, rings, sponges or creams to prevent infection by the human immunodeficiency virus and other sexually transmitted diseases. HIV causes AIDS, which cripples the immune system, leaving patients vulnerable to other infections, cancers and death.
Microbicides are seen as a way for women to protect themselves from HIV, particularly in poor nations where AIDS is widespread, where rape is rampant or where conventional condoms are taboo, not reliably available or where men resist using them. Worldwide, most AIDS cases are spread heterosexually.
About 16 microbicides are in development and five are undergoing testing in thousands of women, mostly in Africa. They are designed to fight HIV infection by preventing the virus from entering cells or multiplying, or by maintaining acidic vaginal conditions. No first-generation microbicide has been approved yet for wide use.