OPTEX 2/3

Reduction of Relapse rate (HCV-RNA positive in serum by a standard HCV-PCR with a detection limit of at least 15 IU/ml) 24 weeks after the end of treatment und thus improvement of sustained virological response rates (SVR)

Virological response rates (HCV-RNA negative in serum by a standard HCV-PCR with a detection limit of at least 15 IU/ml) at the end of therapy

Biochemical responses as determined by ALT and AST levels at the end of treatment and at the end of follow up.

Severity and frequency of adverse event

Analysis of quality of life (with questionnaire SF-36)

1. Male and female patients with HCV-genotype 2/3 chronic hepatitis C documented by detectable plasma HCV RNA (> 15 IU/mL) and positivity of anti-HCV antibodies

2. Age≥ 18 years

3. Compensated liver disease (Child-Pugh Grade A clinical classification)

4. Negative urine or blood pregnancy test (one of the both; for women of childbearing potential) documented within the 24-hour period prior to the first dose of study drug. Additionally, all fertile males and females must be using two forms of effective contraception during treatment and during the 7 months after treatment end. This includes using birth control pills (no interaction with investigational drugs), IUDs, condoms, diaphragms, or implants, being surgically sterilized, or being in a post-menopausal state. At least one contraception method must be of barrier method

5. Ongoing treatment with 1.5 μg/kg Peg-Interferon alpha-2b (PegIntron®) and > 10.6 mg/kg ribavirin (Rebetol®)

6. No rapid virological response (HCV-RNA positive after week 4 of the ongoing therapy)

7. Willingness to give written informed consent and willingness to participate to and to comply with the study protocol

1. Women with ongoing pregnancy or breast feeding

2. Male partners of women who are pregnant

3. Positive tests at screening for anti-HAV IgM Ab, HBsAg, anti-HBc IgM Ab, HBeAg, anti-HIV,HIV-RNA

4. History or other evidence of a medical condition associated with chronic liver disease other than HCV associated (e.g., hemochromatosis, autoimmune hepatitis, alcoholic liver disease, toxin exposures)

5. History or other evidence of bleeding from esophageal varices or other conditions consistent with decompensated liver disease

6. Patients with liver cirrhosis with a lesion suspicious for hepatic malignancy on the screening

7. Absolute neutrophil count (ANC) <750 cells/mm3 at screening

8. Platelet count <50,000 cells/mm3 at screening OPTEX 2/3 – Vs 08 SEP 2008 CONFIDENTIAL 6

9. Hb <10 g/dl at screening

10. Dose modification of Peg-Interferon alpha-2b (PegIntron®) or ribavirin (Rebetol®) during the first 4 weeks of the ongoing therapy

11. Interferon alpha or ribavirin therapy at any time point before the actual ongoing treatment

12. Less than 80% adherence to treatment of the ongoing treatment until randomizaion (week 20-

22 of ongoing treatment)

13. Serum creatinine level >1.5 times the upper limit of normal at screening

14. History of severe psychiatric disease, especially depression (ICD 10 codes F30–F33). Severe psychiatric disease is defined as treatment with an antidepressant medication or a major tranquilizer at therapeutic doses for major depression or psychosis, respectively, for at least 3 months at any previous time. Patients are excluded if any history of suicidal attempts is evident. If hospitalization for psychiatric disease, or a period of disability due to a psychiatric disease are documented, psychiatric consultation is mandatory. Patients with a mild or moderate psychiatric disease (ICD 10 codes F32.0, F32.1, F33.0, F33.1) are only allowed to be included into the trial if a regular monitoring by a psychiatrist is performed during the trial

15. History of a severe seizure disorder or current anticonvulsant use

16. History of immunologically mediated disease (e.g., inflammatory bowel disease, idiopathic thrombocytopenic purpura, lupus erythematosus, autoimmune hemolytic anemia, scleroderma, severe psoriasis, rheumatoid arthritis)

17. History or any other evidence of autoimmune diseases

18. History or other evidence of chronic pulmonary disease associated with functional limitation

19. History of significant cardiac disease that could be worsened by acute anemia (e.g. NYHA Functional Class III or IV, myocardial infarction within 6 months prior to treatment with Peg-Interferon/ribavirin therapy, ventricular tachyarrhythmias requiring ongoing treatment, unstable angina)

20. Evidence of thyroid disease that is poorly controlled on prescribed medications

21. Evidence of severe retinopathy (e.g. CMV retinitis, macular degeneration)

22. History of major organ transplantation with an existing functional graft

23. History or other evidence of severe illness, malignancy or any other conditions which would make the patient, in the opinion of the investigator, unsuitable for the study

24. History of any systemic anti-neoplastic or immunomodulatory treatment (including supraphysiologic doses of steroids and radiation) 6 months prior to the first dose of study drug or the expectation that such treatment will be needed at any time during the study

25. Patients with evidence for tuberculosis

26.Drug abuse within 6 months prior to the first dose of study drug and excessive alcohol consumption. Patients on methadone/polamidone/buprenorphine programs are not excluded

27. Any investigational drug and/or participation in another clinical study prior 6 months to the actual ongoing antiviral treatment

28. Limited contractual capability