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Inteferon-based therapies for chronic Hepatitis C virus infection: an assessment of clinical outcomes

Last updated: May 13, 2004
Issue: 47
Result type: Report

Technology Name

Interferon (IFN)-based antiviral therapies:

  • standard IFN plus ribavirin versus standard IFN therapy alone
  • standard IFN plus ribavirin versus pegylated IFN plus ribavirin


Chronic hepatitis C virus (HCV) infection

Technology Description

IFNs are human proteins that inhibit virus replication in infected cells and boost the natural antiviral capacity of the infected patient. Pegylated IFNs are chemically altered so that they stay inside the body longer. Ribavirin is a synthetic nucleoside analogue thought to inhibit viral reproduction.

The Issue

New Canadian guidelines recommend pegylated IFN alfa plus oral ribavirin as standard treatment for chronic HCV infection. While morbidity and mortality data are needed for properly informing patients and conducting effectiveness and cost-effectiveness analysis, previous reviews of these therapies do not provide this information.

Assessment Objectives

We explored the effectiveness of IFN-based treatments by examining mortality and serious morbidity during chronic HCV infection treatment. We also considered the withdrawals due to adverse events, quality of life and the virologic markers related to use of the following recommended treatments:

  • standard IFN plus ribavirin versus standard IFN therapy alone
  • standard IFN plus ribavirin versus pegylated IFN plus ribavirin.


This review is based on an Agency for Healthcare Research and Quality (AHRQ) systematic review. Studies were re-examined for morbidity and mortality data. In addition, supplemental trial reports were identified from bibliographic databases, manufacturers’ information and from the US Food and Drug Administration’s web site. Data were sought on life-threatening events observed during trials and withdrawals due to adverse events. Surrogate outcomes, including viral response and quality of life measures, were also sought. Individual trial quality was not assessed.


  • Information on quantity or quality of life related to IFN-based treatment is lacking.
  • Morbidity and mortality after therapy with ribavirin added to standard IFN could not be estimated from the randomized trial evidence.
  • Pegylated IFN combined with ribavirin can increase the need for urgent medical attention when compared with standard IFN plus ribavirin.
  • Pegylated IFN plus ribavirin therapy can reduce the risk of persistent viremia and liver enzyme elevation to the greatest degree, when it is compared with standard IFN plus ribavirin therapy or with standard IFN therapy alone.