Clinical Trial Name - S-Citalopram for the Prevention of PEGASYS-Induced Depression

Primary Endpoints - Effect of an antidepressive pre-treatment over two weeks and a continuously concomitant treatment with Escitalopram (S-citalopram) on frequency and severity of depression in patients with chronic hepatitis C (HCV) treated with Peg-interferon alfa-2a (PEGASYS) and ribavirin. The occurrence of moderate to severe depression is measured by the Hamilton Depression Rating Scale 24 weeks after starting interferon therapy. Secondary Endpoints - Quality of life (SF-36) - Drop-out rate - Biochemical response defined by serum glutamyl pyruvic transaminase (GPT) values 24 weeks after treatment - Virological response measured by HCV-RNA at the end of treatment and after six months of treatment - Predictive parameters for patients especially gaining from an antidepressive therapy (e.g. age, gender, weight, height, alanine aminotransferase [ALT] quotient defined as median ALT values before treatment divided by the upper standard value, gamma-glutamyl transpeptidase [GGT], HCV-RNA serum concentration level of fibrosis in liver histology, baseline values of the different psychometric scales) - Comparison of safety placebo versus verum (from psychiatric and hepatological view)