Screening of antiviral drugs for hepadna virus infection in Pekin ducks: a review.

Acyclovir and suramin were examined for their efficacy alone and in combination, against duck hepatitis B virus (DHBV) in persistently infected Pekin ducks. The pharmacokinetics of acyclovir in ducks showed that the peak plasma concentration was reached 30 min after oral administration. Oral acyclovir and suramin administered intravenously suppressed the replication and production of infectious virions as measured by marked reduction of DNA polymerase activity during treatment. However, rebound of enzyme activity was observed soon after cessation of drug therapy. In contrast, sustained reduction of polymerase activity was attained by combined therapy of acyclovir followed by suramin, demonstrating a significant enhancement of anti-DHBV activity which requires confirmation in a larger experimental study. This report reviews the work with the duck model, demonstrating that it is ideal for screening antiviral compounds for treatment of infection with hepadna viruses.