Pitt researcher searches for rectal microbicide to help prevent HIV

By Christen DiClaudio

Dr. Ian McGowan wants you to have safe sex.

But instead of throwing condoms in your face, the… Dr. Ian McGowan wants you to have safe sex.

But instead of throwing condoms in your face, the University of Pittsburgh researcher has an alternative solution. He is developing an anti-HIV gel that serves as both HIV protection and lubricant for rectal sex.

In order to conduct his research, McGowan has received $17.5 million worth of grants from the National Institutes of Health and the National Institute of Child Health and Human Development.

The gel is classified as a microbicide, or topical solution that kills forms of life such as bacteria or parasites.

A microbicide can be used in one of two ways. The first is coitally dependent, meaning that it must be used around the time of sex. It acts on the virus immediately.

The second is more of an anti-rectal-viral drug. It is to be applied daily, building up a concentration of the drug to prevent viral replication if the person is exposed to the virus during rectal contact.

McGowan is specializing in the second type of microbicide, which is the more long-term one.

Research in this field has been executed over the last 15 years — about as long as anti-HIV measures have been taken — but has focused only on developing vaginal microbicides for women to use. The U.S. Food and Drug Administration has not yet approved the vaginal microbicides.

McGowan and his fellow researchers at the University of California, Los Angeles and Johns Hopkins University acknowledge that the HIV epidemic applies to both men and women, so he is working to expand the product’s pertinence to those interested in rectal sex in hopes of “preventing or significantly reducing HIV acquisition.”

The vaginal microbicide cannot be used in the rectum, McGowan explained, because the rectum is a less studied and more delicate area with a one-cell lining compared to the vagina’s 20- to 30-cell lining. He pointed out that many people look to treat the HIV virus once they have already acquired it.

“We need to develop techniques or approaches for prevention,” McGowan said. “People began with condoms, but you can’t always use condoms and particularly in the developing world, women just don’t have the ability to negotiate condom use.”

McGowan said that using this microbicide, women in Africa, for example, can make the choice to fight HIV without having to explain what they’re doing.

“Microbicides can empower women with a product they choose to use,” he said.

Several Pitt students agree.

“This is a great stepping stone for African women,” freshman Neal Burkard said. “I feel that these women should have free access to [the microbicides] once it is fully developed.”

An initial hope for the anti-HIV gel was that in addition to preventing HIV, it would fight other sexually transmitted diseases. Early versions of the microbicides were first tested on animals, whose results looked as though prevention against other STDs might work.

Craig Hendrix, a rectal microbicide researcher from Johns Hopkins University, said in an e-mail that HIV is not present in animals. In addition, the structure and use of the vagina and rectum differ from humans to animals.

“I do think that demonstration of efficacy (encouraging) or toxicity (discouraging) in animal models are very useful in developing rectal microbicides for people, but you still have to do the human studies,” Hendrix said.

The gel was then tested in a large field trial, on women in different areas of Africa because of the high concentration of documented HIV cases in that area.

Although it began to show signs of efficacy against the HIV virus, the product did nothing for the prevention of other diseases like chlamydia, gonorrhea or trichomoniasis.

Newer generations of the developing anti-viral, like the one McGowan is researching now, have a much more narrow focus and are only anticipated to be active against HIV.

“I think that’s a limitation of them,” McGowan said, “but at the end of the day if we can develop something useful for HIV, then that’s a big contribution to public health.”

McGowan said that at the end of the day, condoms remain the best options to prevent HIV.

“All of us in the field would agree that condoms are great, they work when they’re used properly, that’s what you should do,” he said.

In the future, he said he would recommend the use of both a condom and a microbicide together.