Acyclovir prophylaxis and fever during remission-induction therapy of patients with acute myeloid leukemia: a randomized, double-blind, placebo-controlled trial.

PURPOSE: A randomized, double-blind, placebo-controlled trial was performed to estimate the preventive effect of the antiherpetic drug acyclovir on fever, incidence of bacteremia, use of antibiotics, and presentation of infections in patients with acute myeloid leukemia (AML). PATIENTS AND METHODS: Ninety herpes simplex virus (HSV)-seropositive patients aged 18 to 84 years were included. Forty-five patients received acyclovir (800 mg by mouth daily) and 45 placebo. The patients were examined daily for 28 days from the initiation of remission-induction chemotherapy. RESULTS: Fever developed in all patients in both groups. Acyclovir prophylaxis postponed the development of an oral temperature > or = 38.0 degrees C by 3 days (95% confidence interval [CI], 1 to 4 days; P = .03) and the initiation of antibacterial treatment by 3 days (95% CI, 1 to 5 days; P = .008). The duration of fever, use of antibacterial treatment, incidence of bacteremia, and need for systemic antifungal therapy were not affected by acyclovir prophylaxis. At fever development, acyclovir prophylaxis affected the incidence and localization pattern of oral ulcers. Thus, in the acyclovir group, the number of nonfungal oral infections was reduced (relative risk, 0.45 [95% CI, 0.24 to 0.85]) and mainly located on the soft palate (relative risk, 2.49 [95% CI, 1.19 to 5.22]). CONCLUSION: Acyclovir prophylaxis has an impact on fever development, but not on the duration of fever or the need for antibiotics. It does not reduce the incidence of bacteremia, but the presentation of acute oral infections is changed.