Randomized trials have shown the enhancement of efficacy with interferon alfa-2b and ribavirin (IFN-R) in comparison with interferon monotherapy (IFN) as first line treatment of chronic hepatitis C. Further definition of response based on disease, patient, and treatment characteristics is needed to determine the degree of benefit for the various patient subgroups. The aim of this study was to answer this question by analyzing the data from 1,744 naive patients included in trials that compared 24- or 48-week IFN-R treatment. Response factors were identified by logistic regression and receiver operating characteristics curves. Five independent characteristics were associated with a sustained loss of hepatitis C virus (HCV) RNA (<100 copies/mL) 24 weeks after the end of treatment: genotype 2 or 3, baseline viral load less than 3.5 million copies/mL, no or portal fibrosis, female gender, and age younger than 40 years. There was a significant advantage for IFN-R in comparison with IFN alone whatever the combination of factors. The most efficient strategy is to treat all patients for 24 weeks. If the 24-week polymerase chain reaction (PCR) is positive, treatment can be stopped. If the 24-week PCR is negative, patients with fewer than 4 favorable factors should be treated for an additional 24 weeks.
Conclusion: The combination of IFN-R is better as first line treatment than IFN monotherapy. For patients who are PCR negative after 24 weeks of treatment, genotyping and baseline viral load, fibrosis stage, gender, and age are useful predictive factors in determining whether to continue an additional 24 weeks of treatment.