• Sustained virological response (SVR) =HCV RNA negativity (<20 IU/ml) six months after end of treatment.
  

• Change in health related quality as measured by short from 36 (SF-36) from baseline to 6 months after end of treatment.
  
• Sick leave in patients treated for 14 or 24 weeks treatment
  

Patients with HCV genotype 2 or 3 infection are currently recommended 6 months treatment with pegylated interferon alfa (2a or 2b) and ribavirin.Approximately 80% obtain sustained virological response (HCV RNA undetectable 6 months 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 econimical terms. Increasing the treatment duration beyond 6 months does not increase the response rate. Shorter treatment has only been assessed in small trials, but the results have been encouraging. In this randomised, open label,multicenter phase 3 trial with acitive controls patients are treated with pegylated interferon alfa 2a (PegIntron (R), Schering Plough NJ)(1,5 mcg/kg)and ribavirin (Rebetol (R), Schering Plough, NJ) (800-1400mg 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 10 or 20 weeks combination treatment. Patients who are HCV RNA positive are all treated for 20 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 10%. 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.