Intravenous glycyrrhizin for the treatment of chronic hepatitis C: a double-blind, randomized, placebo-controlled phase I/II trial

Abstract

Background: In Japan, glycyrrhizin therapy is widely used for chronic hepatitis C and reportedly reduces the progression of liver disease to hepatocellular carcinoma. The aims of this study were to evaluate the effect of glycyrrhizin on serum alanine aminotransferase (ALT), hepatitis C virus (HCV)-RNA and its safety in European patients.

Methods: Fifty-seven patients with chronic hepatitis C, non-responders or unlikely to respond (genotype 1/cirrhosis) to interferon therapy, were randomized to one of the four dose groups: 240, 160 or 80 mg glycyrrhizin or placebo (0 mg glycyrrhizin). Medication was administered intravenously thrice weekly for 4 weeks; follow up also lasted for 4 weeks.

Results: Within 2 days of start of therapy, serum ALT had dropped 15% below baseline in the three dosage groups (P < 0.02). The mean ALT decrease at the end of active treatment was 26%, significantly higher than the placebo group (6%). A clear dose-response effect was not observed (29, 26, 23% ALT decrease for 240, 160 and 80 mg, respectively). Normalization of ALT at the end of treatment occurred in 10% (four of 41). The effect on ALT disappeared after cessation of therapy. During treatment, viral clearance was not observed: the mean decrease in plasma HCV-RNA after active treatment was 4.1 x 10(6) genome equivalents/mL (95% confidence interval, 0-8.2 x 10(6); P > 0.1). No major side-effects were noted. None of the patients withdrew from the study because of intolerance.

Conclusions: Glycyrrhizin up to 240 mg, thrice weekly, lowers serum ALT during treatment, but has no effect on HCV-RNA levels. The drug appears to be safe and is well tolerated. In view of the reported long-term effect of glycyrrhizin, further controlled investigation of the Japanese mode of administration (six times weekly) for induction appears of interest.