OBJECTIVES: Several randomized studies confirmed the efficacy and safety of peginterferon-based antiviral therapy for patients with hepatitis C virus infection. However, various types of patients who were not included in those studies are possibly seeking antiviral therapy in daily practice. The study aim was to analyze those patients and their treatment situation in a real-world setting. METHODS: A large claims database (Medical Data Vision, Japan; 4/2010 - 6/2012) was retrospectively analyzed. The study patients were those who had evidence of CHC (ICD10: B182) and initiated either the combination therapy with peginterferon + ribavirin (PR) or the triple therapy with peginterferon + ribavirin + telaprevir (PR+T) from November, 2011. RESULTS: A total of 207 patients were identified, with 136 patients initiating PR (median age 56 years) and 71 patients initiating PR+T (median age 60 years). A quarter of patients were aged ≥65 in both therapy groups. 6% of patients given PR and 13% of patients given PR+T were previously diagnosed with hepatocellular carcinoma (HCC). Mean initial doses of peginterferon and ribavirin were similar between PR and PR+T however, mean adherence to the ribavirin dose in PR+T was 78% and lower than PR (95%). Patients requiring hospitalizations for treatment initiation were significantly different between PR and PR+T (71% vs. 93%, P<0.01); lengths of stay were 11.8 and 18.5 days in PR and PR+T, respectively (P<0.01), P-values were not changed after adjusting for patient age, gender, and previous diagnosis of HCC and cirrhosis. CONCLUSIONS: The study found that a quarter of patients were elderly and the majority of patients required hospitalization to start treatment with either PR or PR+T. More effective and safer treatment is desirable. Further research is needed to understand how differences in the characteristics of the patients treated with PR+T vs. PR impact on treatment adherence and hospitalization patterns observed.