Efficacy of Peginterferon Alfa-2b (SCH 054031) vs Glycyrrhizin in Interferon (IFN)-Treated Patients With Chronic Hepatitis C and F2/F3 Liver Fibrosis (P04773)

Inclusion Criteria: * Patients with chronic hepatitis C previously treated with interferon * At least 20 years of age * Liver fibrosis score rated as F2 or F3 based on the result of liver biopsy at screening * Female patients willing to use contraception * Body weight from 35.0 kg to 110.0 kg (inclusive) * Positive for hepatitis C virus ribonucleic acid (HCV-RNA) by qualitative assay * Patients who meet the following laboratory criteria: * Serum alanine aminotransferase (ALT) level: \>60 IU/L * Neutrophil count: \>=1,200/mm\^3 * Platelet count: \>=100,000/mm\^3 * Serum potassium level: \>=3.5 mEq/L Exclusion Criteria: * Patients who received interferon therapy within 90 days of Screening * Patients who have received antiviral agents or antitumor agents, or immunomodulator therapy (including chronic glucocorticoids and radiotherapy) within 90 days of Screening (excluding local administration and topical use) * Patients who have received other investigational drugs within 90 days of Screening * Hepatitis B surface antigen (HBs)positive * Antinuclear antibody titer of 1:320 or higher * Creatinine level exceeding the upper limit of the reference range measured at screening test 2; * Fasting blood glucose level of \>=126 mg/dL * Patients on insulin therapy regardless of the fasting blood glucose level * Patients who have a concurrent or past history of any of the following conditions: liver cirrhosis, liver failure, or liver carcinoma; hepatic encephalopathy, esophageal varices requiring treatment, or ascites; suicidal attempt or ideation; epileptic seizures requiring drug therapy; angina pectoris, heart failure, myocardial infarction or fatal arrhythmia; autoimmune disease (Hashimoto's disease \[chronic thyroiditis\], Crohn's disease, ulcerative colitis, rheumatoid arthritis, idiopathic thrombocytopenic purpura, systemic lupus erythematosus, autoimmune hemolytic anemia, scleroderma, etc.); malignant tumors (it is permitted to register patients with at least 5 years after cure). * Patients who concurrently have any of the following conditions: liver disease such as autoimmune hepatitis, alcoholic liver injury, and drug-induced hepatitis; hemophilia; depression or schizophrenia which requires treatment; hypertension which cannot be controlled by drug therapy or arrhythmia which requires treatment, chronic pulmonary disease; abnormal thyroid function that cannot be controlled by drug therapy; organ transplants (other than corneal, hair transplant, etc.); aldosteronism, myopathy, or hypokalemia. * Patients with a history of hypersensitivity to interferon preparations or biological products such as vaccines * Patients with a history of hypersensitivity to monoammonium glycyrrhizinate, glycine, or L-cysteine monohydrochloride; * Women who are pregnant or lactating, and women in whom pregnancy cannot be ruled out based on the result of serum human chorionic gonadotropin (HCG) measurement at Screening