Biochemical and virological response of chronic hepatitis C after treatment with interferon-alpha for 6 or 12 months: predictors of sustained remission.

Objective: To evaluate the biochemical and virological response in chronic hepatitis C patients treated with interferon-alpha at the usual dosage of 3 MU thrice weekly for 6 or 12 months, and to analyse the significance of clearance of serum HCV RNA and of HCV genotype in the prediction of sustained biochemical remission.

Setting: Liver Unit, Western Attica General Hospital, Athens, Greece.

Participants: Sixty consecutive patients with histologically confirmed chronic hepatitis C.

Interventions: All patients received interferon-alpha-2b in a dose of 3 MU thrice weekly for 6 (n = 26) or 12 (n = 34) months. Serial serum samples were retrospectively tested for the presence of HCV RNA by a polymerase chain reaction assay and pretreatment serum samples for the determination of HCV genotype.

Results: Sustained biochemical response rate was significantly higher in the 12-month group (62% vs. 35%, P = 0.037). Clearance of serum HCV RNA at the end of treatment was achieved in 33 (58.9%) of the 56 patients with detectable pretreatment HCV RNA. HCV RNA reappeared in serum significantly more often in patients treated for 6 than for 12 months (35.7% vs. 5.3%, P = 0.037). Serum HCV RNA after 6 months of therapy was a prognostic factor of sustained biochemical response, which was observed in 75% of the HCV RNA-negative and in only 16.7% of the HCV RNA-positive patients (OR 0.067, P < 0.001). Moreover, in patients negative for HCV RNA after 6 months of therapy, 12 months' treatment resulted in a higher sustained response rate than did 6 months' (89% vs. 57%, P = 0.05). HCV genotype 1 was associated with a significantly lower sustained response rate (30% vs. 60.7%, P = 0.035), whereas 12 months' treatment induced sustained remission significantly more often only in patients with genotype 1 (6/12 vs. 0/8, P = 0.024).

Conclusion: In chronic hepatitis C treatment HCV genotype and serum HCV RNA after 6 months of therapy are strong predictive factors of a sustained response, and a 12-month rather than a 6-month interferon regimen may induce a more persistent clearance of HCV RNA in total and a higher sustained response rate in patients with HCV genotype 1 and in those who clear HCV RNA after 6 months of therapy.