Abstract

In eight HBs and HBe antigen positive patients with chronic active liver disease, adenine arabinoside 5'-monophosphate (ARA-AMP) given, intravenously or intramuscularly, six or 12 hours, produced inhibition of viral replication. In five patients given a short course of therapy with 10 or 15 mg/kg/day this effect was transient and in two thrombocytopenia occurred. In three further consecutive cases given a longer course with 5 mg/kg/day after five days of the high dose, thrombocytopenia was not seen and inhibition of viral replication for up to 13 months occurred. These patients lost HBV-DNA polymerase activity, serum viral DNA and HBeAg, developed anti-HBe, and HBsAg concentrations decreased. A course of twice daily intramuscular ARA-AMP given for three to five weeks as an outpatient may be expected to produce a long-term reduction in infectivity.