Hepatitis C virus infection is affecting an estimated 200 million people worldwide and 210 thousand in
Iran. It is a major cause of morbidity and mortality from liver disease. Interferon-alpha is the choice of
treatment but interferone (IFN) with ribavirin is known more effective recently. This study evaluated
effect of IFN on Iranian patients and predict response to therapy. This is a quasi experimental study on 33
patients of chronic hepatitis C that are treated by IFN-2a, 3 Mega units, three times in week for 12 months,
subcutaneously. We assessed ALT, AST, alkaline phosphatase, total and direct billirubine at first, second
week and every month till 12 months. HCV-RNA and biopsy were done at first and end of study. T test,
chi2, ANOVA, correlation coefficient and regression models were used for analysis. %82.7 were ejucated
under diploma. AST, ALT and alkaline phosphatase were decreased under normal range during treatment
significantly(P=0.00005, P=0.0005 & P=0.001). Liver enzymes and billirubine normalized 2-4 months
after treatment and the first biochemical break through was during first 6 months. %86.7 of all patients
response to therapy biochemically. Percent of patients with negative HCV-RNA was more in the end of
study significantly. (P<0.009) Mean biopsy score decreased significantly(P=0.03). Interferone-alpha
decreases progression of liver disease, hepatocellular carcinoma, transplantation need and probably death.
Total dose of IFN is more important than weekly dose or duration of therapy. Selection of patients with
high probability response to therapy, instead of all of patients should be done. Biochemical response was
high and quite acceptable. Significant models for prediction of the first time of response and the first
biochemical break through during therapy are effective, cheap, easy and available. Results of this study
suggest to give information about chronic hepatitis C to patients and doctors, too.