The combination of pegilált interferon plus ribavirin is significantly more effective than conventional interferon plus ribavirin, and is thus the current therapy of choice for patients with chronic hepatitis C. Forty-eight weeks of treatment with combination of pegilált interferon plus ribavirin has produced overall sustained virologic response 54-56% in patients with chronic hepatitis C. This article summarize the new therapy of chronic hepatitis C, the antiviral therapy of hepatitis C virus patients with normal aminotransferase levels, the therapy in patients with compensated cirrhosis and who were nonresponders to previous combination therapy, the effect of antiviral therapy on necroinflammation and fibrosis, and the favourable effect of haemopoetic growth factors on results of antiviral therapy. A substantial proportion of patients with chronic hepatitis C have persistently normal alanin-aminotransferase levels. Many studies have indeed provided evidence that although the majority of hepatitis C virus patients with normal alanin-aminotransferase may have active and progressive liver disease. Initiation of antiviral therapy might be decided mainly on the basis of histological findings. Extending the treatment duration from 48 to 72 weeks in patients with hepatitis C virus genotype 1 significantly reduces relapse rates and increases sustained virological rates. Induction phase with a higher dose of pegilált interferon may be of value in improving outcomes in patients with genotype 1 who were nonresponders to previous combination therapy. The combination of pegilált interferon and ribavirin was effective and well tolerated in patients with compensated cirrhosis. Interferon-based therapy may reduce hepatic inflammation in the absence of a sustained virologic response. This results suggest that interferon maintenance therapy may slow disease progression. The virologic response rates could be improved by utilizing haemopoetic growth factors, as opposed to reducing the ribavirin and interferon dose.