Herpes treatment could slow HIV progression in people living with both viruses

Feb 25 2007

Treatment of genital herpes could slow the progression of HIV in people living with both viruses, according to a study published in the Feb. 22 issue of the New England Journal of Medicine, Reuters reports (Emery, Reuters, 2/21).

The study, led by Nicolas Nagot of the London School of Hygiene and Tropical Medicine, assigned 140 women in Burkino Faso who had both herpes and HIV to take either the herpes treatment valacyclovir, sold by GlaxoSmithKline under the brand-name Valtrex, or a placebo daily for three months.

The women were not taking antiretrovirals. Researchers took vaginal swabs and blood samples twice weekly during the study period to measure HIV viral loads.

The study found that the viral loads among participants who took valacyclovir decreased from an average of 20,000 virus copies per milliliter of blood to 8,000 copies per milliliter of blood, compared with an increase to 63,000 copies per milliliter of blood from 50,000 copies per milliliter among the placebo group.

In addition, 13% of the women in the valacyclovir group had detectable levels of HIV in the genital tract, compared with 27% of women in the placebo group.

Although the study did not examine if the drug reduced the risk of HIV transmission, researchers have found that the risk of HIV transmission increases with higher viral loads (Chang, AP/Forbes, 2/21).

About 70% of HIV-positive people in Europe and 90% in Africa also have the genital herpes virus, HSV-2, Reuters reports.

According to the researchers, the effects of valacyclovir increased during the study, meaning that a "longer duration of treatment might have led to an even greater reduction" in HIV viral loads, the study said (Reuters, 2/21).

Study co-author Philippe Mayaud of the LSHTM said more research on herpes control methods, including a herpes vaccine, is necessary.

Lawrence Corey, a researcher at the University of Washington who was not involved with the study, said the findings "open some potential avenues to slowing down the HIV epidemic."

According to the AP/Forbes, some HIV/AIDS specialists have said that herpes drugs likely will not be used as a first-line treatment for HIV prevention but that herpes treatments could be a useful tool for HIV prevention in developing countries with limited access to antiretrovirals.

The Bill & Melinda Gates Foundation is funding a larger study to determine whether treatment with the herpes drug acyclovir can prevent HIV transmission, AP/Forbes reports (AP/Forbes, 2/21).

The study is available online.