Telaprevir Exposure and Severe Anemia in HCV Infected Patients Treated by Tri-therapy

Inclusion Criteria: * Man or woman older than 18 yr. 2- HCV genotype 1 infection as confirmed by a positive viral load 6 months after the selection visit or confirmed by the mean of a liver biopsy within 1 year before screening for the study. 3- Patient with one of the following criteria: Patient naive of any treatment against HCV infection Or Prior null responder patient: patient previously treated by ribavirin/PEG-INF for at least 12 weeks and whom HCV viral load decline was \<2 log at week 12 Or Prior partial responder patient: patient previously treated by ribavirin/PEG-INF for at least 12 weeks, who never had a negative viral load while the viral load decline was \>2 log at week 12 Or Prior relapser patient: patient previously treated by ribavirin/PEG-INF for 48 weeks, with a negative viral load at the end of treatment and a positive viral load 6 months later 4- Patient who has stopped his treatment for at least 12 weeks 5- Patient who had a liver biopsy or a Fibroscan within the 24 months before the start of the study with a Metavir fibrosis score F ≥ 3. 6- Patient who fulfills criteria for telaprevir treatment as defined by the licence 7- Patients who accepts to use 2 contraceptive methods until 6 months after the end of the treatment 8- Patient who had given his written informed consent 10- Patient insured under the french social security system Exclusion Criteria: 1- Infection/co-infection by HCV genotype different than genotype 1 2- Patient with a medical contraindication to PEG-INF or ribavirin 3- Patient with history of allergy or intolerance to telaprevir 4- Patient using contraindicated drugs 5- Patient with history of decompensated liver disease and/or presenting biochemical measurements as follows at the inclusion visit: * International Normalized Ratio (INR) \> 1,5 * Albumin \<3,3 g/dl * Total bilirubin\>1,8 N apart for patient with Gilbert syndrome 6- Liver disease from other causes 7- Patient with hepatocellular carcinoma or history of cancer 8- Patient with a history of graft transplantation and treated by immunosuppressive drugs 9- Patient who are regularly treated by corticosteroids 11- Patient with hemophilia or coagulation troubles 12- HIV or HBV co-infection 14- Patient with body mass index\> 30 kg/m2.