- Fibrosis stage have to be documented by a significant liver biopsy (cumulative length ≥ 15 mm or ≥ 6 portal spaces), within 3 years. Patients with a previous liver biopsy exhibiting cirrhosis lesions (METAVIR F4) are allowed to enter the study without a new biopsy. The proportion of patients with cirrhosis lesions (METAVIR F4) is limited to 50% of all patients.