Evaluation of the antiviral effects of adenine arabinoside on chronic HBV infection.

Five male patients with HbsAg-positive liver disease were treated with ara-A at dosages ranging between 5 mg and 10 mg/kg/day for five days. Before treatment, all of them had detectable DNA polymerase activity and HbeAg in their sera. The five-day course of the drug resulted in a rapid fall in DNA polymerase activity in every patient, the effect being dose-dependent. The amount of circulating Dane particles also decreased simultaneously, or with a short time lag, with the fall of the enzyme activity. The following decrease in HBeAg concentration was observed in all patients, and it was also noteworthy that antiHBe response was found in two of the five. HBsAg titers were significantly diminished in two patients. In the present series of ara-A treatment, these effects were temporary in two patients, while, in the remaining three, they lasted for two to three months. Ara-A had no serious side effects at dosages of 10 mg/kg/day or less, and can thus be counted among the valuable therapeutic drugs against chronic HBV infection.