A Randomized Trial of 24-Week Versus 48-Week Courses of Peginterferon Plus

High rate of infection of Hepatitis C Virus(HCV) Genotype 6 was recently confirmed in Southern China. Recent study implied chronic hepatitis C genotype 6 responds better to the 48-week treatment with pegylated interferon and ribavirin than genotype 1. Approximately 75.7% obtain sustained virological response (HCV RNA undetectable 24 weeks after treatment) to this approach. However, the treatment is associated with many and sometimes serious side effects. In addition, the treatment is costly also in economical terms. Shorter treatment for chronic hepatitis C genotype 6 is necessary to be assessed.

In this randomised,open label,multicenter phase 3 trial with active controls patients are treated with pegylated interferon alfa 2a (180ug/week)and ribavirin(800-1200mg based on weight)for 4 weeks. Those who are HCV RNA negative at week 4 (<50 IU; Cobas Amplicor Monitor Test, Roche Diagnostic) are defined as rapid virological responders and randomised to either an additional 20 or 44 weeks combination treatment. Patients who are HCV RNA positive are all treated for 44 more weeks. The endpoint is sustained virological response defined as undetectable HCV RNA 24 weeks after end of treatment.

Our hypothesis is that there is no important difference in the effect in the two groups.

This is a non-inferiority trial. The smallest difference considered to be clinically important is 15%. Thus to state "non-inferiority" the 95% confidence interval of the observed difference between the groups shall not overlap 10%. Both intention to treat and and per protocol analyses will be published. Conclusion will be conservative and based on the analysis who detect the biggest difference.