New nucleoside analogues for chronic hepatitis B.

In recent years, an in vitro system for screening nucleoside analogues against hepatitis B virus has yielded several compounds with a high therapeutic index. Phase I and II studies have also shown a potent in vivo antiviral effect of fialuridine and lamivudine in patients with chronic hepatitis B. The use of fialuridine was associated with unexpectedly severe mitochondrial dysfunction; in contrast, lamivudine had virtually no side-effects. Experience in liver transplant patients with recurrent hepatitis B shows that famciclovir may be another effective antivirotic drug with good tolerance.