Influence of Nevirapine on HCV Viral Load

Inclusion Criteria: * HIV infection. * Older than 18 years. * Chronic hepatitis C. * Undetectable HIV viral load during one year before starting study. * To have not received HCV therapy during one year before starting study. * To have not started efavirenz or protease inhibitors o nucleoside analogs during 6 months before starting study. * Non contraindications for drugs included in this study. * To change an antiretroviral regimen including efavirenz or protease inhibitors by nevirapine due to side effects, interactions or pregnancy (NVP group) * To continue with a antiretroviral regimen including efavirenz or protease inhibitors (non-NVP group) Both groups will be matched according to these variables: * Liver stiffness. * HCV genotype. * Hospital. * Time from starting antiretroviral therapy. * Previous third drug (EFV or PI) to introduction of NVP. Exclusion Criteria: * HCV therapy during follow-up