(CN) - A treatment for genital herpes has shown an ability to reduce HIV levels in herpes-free patients, according to a study just announced by the government.
Valacyclovir is commonly used to control the virus that causes genital herpes, but researchers in Cleveland, Atlanta and Peru have discovered it also has an effect on the virus that causes AIDS, the March 13 release from the National Institutes of Health says.
After testing the drug on 18 patients who had HIV, but not genital herpes, researchers found that the presence of herpes was not necessary for the drug to reduce HIV levels.
An NIH scientist behind the study called the results "very encouraging."
"If valacyclovir's effectiveness against HIV can be confirmed in a larger cohort, it could be added to the mix of drugs used to suppress the virus, and might prove especially helpful in cases in which HIV has developed resistance to other drugs," Leonid Margolis, who was senior author of the study, said in a statement.
Margolis heads the Section on Intercellular Interactions at the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD).
The same research team published a 2008 study that showed that acyclovir, a drug similar to valacyclovir, suppresses HIV in herpes-affected human tissues.
During the first 12 weeks of the valacyclovir study, nine of the patients took the drug twice a day while the other nine took a placebo. The groups switched for the final two weeks.
HIV patients often take a "cocktail" of drugs, because one medication is not strong enough to control the virus. The use of several drugs also impedes HIV from developing a resistance to the drugs.
According to the NIH report, the researchers acknowledge that the virus could eventually resist valacyclovir over time.
"Given the ability of the drug to lower HIV levels, however, the researchers believe that valacyclovir could one day be added to the cocktail of drugs given to HIV-infected people," the NIH said.