Systematic review: Peginterferon vs. standard interferon in the treatment of chronic hepatitis C

Background: Randomized controlled trials over the last decade have demonstrated incremental improvement in the treatment efficacy of chronic hepatitis C with combination interferon and ribavirin therapy when compared with interferon monotherapy. Aim: To perform a systematic review of clinical trials directly comparing interferon formulations to test the hypothesis that a true difference in terms of efficacy exists between standard interferon (with and without ribavirin) and peginterferon (with and without ribavirin). Methods: A search of the on-line bibliographic databases MEDLINE and PUBMED was performed independently by two authors to identify all relevant articles. In addition, the reference sections of all relevant articles were manually searched to identify any missed articles. Quality was assessed using the Jadad scale, which is an accepted scale specific for randomized controlled trials. A priori, it was decided to include only articles with a Jadad score of three or higher in the final analysis. Data were abstracted on to pre-determined abstraction sheets. The inclusion of articles, the data abstracted and the methodological score differences were adjudicated by consensus with agreement of the authors performing the search. Results: Seven citations of randomized controlled trials, comparing at least two different interferon formulations and evaluating the sustained virological response as a primary end-point, were identified. These relevant articles were abstracted, and five of the seven were found to have a Jadad score of three or higher and comprised the final set of citations reviewed. The studies consistently demonstrated that peginterferon monotherapy was superior to standard interferon, even in patients with advanced fibrosis. With regard to combination interferon therapy, only two high-quality articles compared peginterferon plus ribavirin with standard interferon plus ribavirin. Both studies demonstrated that the overall sustained virological response was statistically better with peginterferon plus ribavirin. Conclusions: On the basis of this systematic review, peginterferon-based regimens are superior to standard interferon-based regimens for the treatment of chronic hepatitis C.