HIV levels declined in patients who did not have herpes but took the antiherpes drug valacylovir in a double-blind placebo-controlled crossover trial.
The study showed that the drug “likely reduced HIV levels by interfering directly with HIV’s reproductive machinery and did not require the presence of [herpes],” according to a written statement issued by the U.S. National Institutes of Health.
Valacyclovir is the prodrug of acyclovir. Previous studies showed that acyclovir reduced the plasma HIV viral load in patients coinfected with HIV and herpes simplex virus 2 (HSV-2), which researchers had attributed to a suppression of HSV-2–mediated inflammation. The new study debunked that hypothesis, however, because none of its participants had HSV-2.
This trial’s 18 participants were infected with HIV-1, had CD4 cell counts of at least 500 cells/mcL, and were not taking antiretroviral therapy. Each patient received 500-mg doses of valacyclovir, twice a day, for 12 weeks, Dr. Christophe Vanpouille and his associates reported.
Find the full study in Clinical Infectious Diseases.