Acyclovir Prophylaxis Reduces the Incidence of Herpes Zoster Among HIV-Infected Individuals: Results of a Randomized Clinical Trial.

Human immunodeficiency virus (HIV)-infected persons have higher rates of herpes zoster than HIV-uninfected individuals. We assessed whether twice daily treatment with 400 mg of oral acyclovir reduces the incidence of herpes zoster in a randomized, double-blind, placebo-controlled trial among 3408 persons coinfected with HIV and herpes simplex virus type 2. During 5175 person-years of follow-up, 26 cases of herpes zoster occurred among those assigned acyclovir, compared with 69 cases among those assigned placebo (rates, 1.00 and 2.68/100 person-years, respectively), a relative decrease of 62% (hazard ratio, 0.38; 95% confidence interval, .24-.67; P < .001). Daily acyclovir prophylaxis significantly reduced herpes zoster incidence among HIV-infected persons.