Interferon induction followed by PEG-interferon combined with ribavirin and amantadine for treatment of naive chronic hepatitis C patients with genotype 1 or 4.

1. Patients which are serum HCV-RNA positive by PCR and with genotype 1 or 4;

2. Patients who never have used antiviral therapy for chronic hepatitis C;

3. Male and female patients >= 18 and < 65 years of age;

4. Patients who have given written informed consent after a detailed explanation of the study by the investigator.

1. Patients who are pregnant and patients (male or female) who are not willing to practice adequate contraception during the treatment period and up to 6 months after ending the treatment period;

2. Patients who are HBsAg or HIV antibody positive or who are unwilling to have these tests done;

3. Patients with decompensated cirrhosis (e.g. albumin < 32g/L, PTT prolonged > 4 s, bilirubin 2x > upper limit of normal, AT III < 60%, ascites, GI bleeding, encephalopathy);

4. Patients with a history of i.v. drug use within 6 months prior to entry;

5. Patients with any clinically significant systemic disease other than liver disease (e.g. malignant disease, congestive heart failure, uncontrolled diabetes mellitus, renal failure (serum creatinine > 181 micromol/ml), or autoimmmune disease;

6. Patients with a history of auto-immune hepatitis;

7. Patients using immune modulating treatment during the 6 months prior to study entry;

8. Patients with a history of hypersensitivity to any component of the study drugs;

9. Patients with pre-existing bone marrow depression such as hematocrit < 32%, white blood cell count < 3.0x10E9/L, granulocytes < 1.5x10E9/L, platelets < 100x10E9/L neutrophil count < 1.5x10E9 or Hemoglobin < 8.1 mmol/L for males and < 7.0 mmol/L for females;

10. Patients with severe depression or other psychiatric illness;

11. Patients with a history of epilepsy, or other clinically significant CNS dysfunction;

12. Patients with any condition, that in the opinion of the investigator, might interfere with the outcome of the study.