Identifying HCV genotype 1 patients at risk of relapse

Objective: The objective of this analysis was to identify predictors of relapse in genotype 1 patients after 48 weeks of treatment with peginterferon plus ribavirin. Methods: Retrospective analysis of data from treatment-naive genotype 1 patients with an end-of-treatment response after 48 weeks of treatment with peginterferon α-2a plus ribavirin 1000/1200 mg/day in the Canadian Pegasys Expanded Access Program. Results: Among treatment-naive genotype 1 patients with an end-of-treatment response (n = 432), the sustained virological response status was known for 405 individuals (sustained virological response n = 328, 81%; relapse n = 77, 19%). Early virological response rates at week 12 were similar in relapsers (98.7%) and sustained responders (98.5%). More relapsers (12 of 77, 15.6%) than sustained responders (15 of 328, 4.6%) had quantifiable hepatitis C virus (HCV) RNA (≥600 IU/ml) at week 12 and, among these patients, mean and maximum HCV RNA levels were higher in relapsers, although the median values were similar. Factors significantly associated with relapse in the multiple logistic regression analysis include older age (odds ratio: 1.48 per decade, 95% confidence interval: 1.06-2.07; P = 0.023), Caucasian ethnicity (odds ratio: 3.23, confidence interval: 1.25-8.33; P = 0.016), higher baseline serum HCV RNA level (P = 0.005), the drop in HCV RNA between baseline and week 12 (P = 0.026), and the interaction between baseline HCV RNA level and the decrease in HCV RNA between baseline and week 12 (P = 0.032). Conclusion: Older age, Caucasian ethnicity, and high baseline HCV RNA level, and a smaller decrease in HCV RNA between baseline and week 12 predict a relapse in genotype 1 patients.