In a significant step toward reducing the threat of HIV, UC Merced Professor Patricia LiWang has designed what may be the most effective chemical inhibitor against infection of the virus.

"We need a fairly wide arsenal of HIV drugs because the virus is always mutating," LiWang said. "Drugs become less effective as time goes on."

LiWang's inhibitor, a novel combination of two existing drugs, has a strength that ranges from several times better than existing inhibitors to several hundred times better, depending on the strain of HIV. The inhibitor works by blocking HIV from entering a person's cell at two different steps of viral entry. This so-called "entry inhibition" is at the forefront of new strategies for stopping the virus. Other existing inhibitors have different strategies, such as preventing HIV from carrying out activities like replicating or integrating into the human genome.

There are hundreds of different strains of HIV, LiWang said, and the virus mutates when it gets inside a person's body.

"However, since this drug is a combination of two inhibitors, it would be nearly impossible for a virus to mutate so it wouldn't get hit with either one of these drugs," she explained.

The research is an example of UC Merced's faculty addressing real-world health problems.

The inhibitor is a special protein produced from harmless bacteria, which allows for large amounts to be made. The inhibitor could be added to a vaginal cream that woman could apply to guard against the virus.While condoms protect against HIV, many men in sub-Saharan Africa and other areas won't wear them, and women often don't have a choice in the decision.

LiWang's findings were published in August in The Journal of Biological Chemistry. Graduate Student Bo Zhao was the first author on the paper. Marie K. Mankowski, Beth A. Snyder and Roger G. Ptakfrom the Southern Research Institute were also part of the study.

Though the discovery is promising, much more testing and development is needed before it could be used by people in countries ravaged by the AIDS epidemic. The next step would be to see if it causes inflammation or any side effects. Clinical trials would be years off.

"We hope that a company is interested in it and we hope to get funding to keep developing it and see why it works," LiWang said.