Pegylated interferon α plus ribavirin for the treatment of chronic hepatitis C: a multicentre independent study supported by the Italian Drug Agency.

Data on the efficacy of Peg-interferon/ribavirin therapy for chronic hepatitis C are mostly derived from treatment of selected patients enrolled in clinical trials. This study aimed to assess the effectiveness of Peg-interferon/ribavirin therapy in "real world" chronic hepatitis C patients in Italy.Independent observational multicentre study including consecutive patients receiving Peg-interferon/ribavirin in the 18 months before (retrospective phase) and after (prospective phase) the start of the study.4176 patients were eligible. The final study population consisted of 2051 patients in the retrospective and 2073 in the prospective phase. Sustained virological response was achieved by 1036 patients (50.5\%) during the retrospective phase: 325 were genotypes 1/4 (34.1\%) and 684 were genotypes 2/3 (67.2\%) and by 800 patients (38.6\%) during the prospective phase: 300 were genotypes 1/4 (28.4\%) and 473 were genotypes 2/3 (51.5\%). During multivariate analysis genotypes 2/3 were significantly associated with higher sustained virological response rates; cirrhosis and γ-glutamil-transpeptidase >2 times the normal limit were associated with poorer response.The response to Peg-interferon/ribavirin therapy in "real world" clinical practice is distinctly lower than in registration trials. The difference in response rates was more pronounced among easy-to-treat than among difficult-to-treat hepatitis C virus genotypes.