Histologic Outcomes in Hepatitis C-Infected Patients with Varying Degrees of Virologic Response to Interferon-Based Treatments

Patients with chronic hepatitis C with partial virologic response or nonresponse to interferon-based therapies can experience treatment-related improvements in liver histology. This retrospective analysis assessed the histologic response to treatment in patients with varying degrees of virologic response (sustained virologic response [SVR], breakthrough, relapse, or nonresponse), time to hepatitis C virus (HCV) RNA undetectability, and duration of viral suppression. Patients (HCV genotypes 1-6) with baseline and follow-up liver biopsies from eight phase 2 to phase 4 interferon-based trials were analyzed. Blinded biopsies were evaluated by a single pathologist. Improvements or worsening of METAVIR necroinflammatory activity and fibrosis were defined as increase or decrease of >= 1 grading category from baseline to 24 weeks after end of treatment. A majority of the 1571 patients with paired biopsy data were white, male, with HCV genotype 1/4, baseline HCV RNA levels >800,000 IU/rnL, and baseline alanine aminotransferase levels <= 3 x upper limit of the normal range; mean baseline activity and fibrosis scores were 1.8 and 1.7, respectively. Overall, 80% of patients received peginterferon alfa-2a monotherapy or peginterferon alfa-2a/ribavirin combination therapy. Mean treatment duration was 46 weeks. There was a positive correlation between the degree of virologic response and improvements in METAVIR activity and fibrosis, and an inverse correlation with worsening activity and fibrosis (all comparisons, P < 0.0001). Patients with SVR had the greatest histologic benefit. As a combined group, relapsers and patients with breakthrough had significantly greater benefits than nonresponders (activity, P = 0.0001; fibrosis, P = 0.003). Consistent with these results, a better histologic response was correlated with a shorter time to undetectable HCV RNA and a longer duration of viral suppression (all comparisons, P < 0.0001). Conclusion: In patients with chronic hepatitis C who were treated with interferon-based therapies, histologic benefits may be observed even in the absence of an SVR. (HE, PATOLOGY 2010;52:1193-1200)