PEG IFN alfa-2a vs. alfa-2b: And the winner is ...?

Peginterferon alfa-2b or alfa-2a with ribavirin for treatment of hepatitis C infection. McHutchison JG, Lawitz EJ, Shiffman ML, Muir AJ, Galler GW, McCone J, Nyberg LM, Lee WM, Ghalib RH, Schiff ER, Galati JS, Bacon BR, Davis MN, Mukhopadhyay P, Koury K, Noviello S, Pedicone LD, Brass CA, Albrecht JK, Sulkowski MS; IDEAL Study Team. N Engl J Med 2009 Aug 6;361(6):580-93. BACKGROUND: Treatment guidelines recommend the use of peginterferon alfa-2b or peginterferon alfa-2a in combination with ribavirin for chronic hepatitis C virus (HCV) infection. However, these regimens have not been adequately compared. METHODS: At 118 sites, patients who had HCV genotype 1 infection and who had not previously been treated were randomly assigned to undergo 48weeks of treatment with one of three regimens: peginterferon alfa-2b at a standard dose of 1.5microg per kilogram of body weight per week or a low dose of 1.0microg per kilogram per week, plus ribavirin at a dose of 800 to 1400mg per day, or peginterferon alfa-2a at a dose of 180microg per week plus ribavirin at a dose of 1000 to 1200mg per day. We compared the rate of sustained virologic response and the safety and adverse-event profiles between the peginterferon alfa-2b regimens and between the standard-dose peginterferon alfa-2b regimen and the peginterferon alfa-2a regimen. RESULTS: Among 3070 patients, rates of sustained virologic response were similar among the regimens: 39.8% with standard-dose peginterferon alfa-2b, 38.0% with low-dose peginterferon alfa-2b, and 40.9% with peginterferon alfa-2a (P=0.20 for standard-dose vs. low-dose peginterferon alfa-2b; P=0.57 for standard-dose peginterferon alfa-2b vs. peginterferon alfa-2a). Estimated differences in response rates were 1.8% (95% confidence interval [CI, -2.3 to 6.0) between standard-dose and low-dose peginterferon alfa-2b and -1.1% (95% CI, -5.3 to 3.0) between standard-dose peginterferon alfa-2b and peginterferon alfa-2a. Relapse rates were 23.5% (95% CI, 19.9 to 27.2) for standard-dose peginterferon alfa-2b, 20.0% (95% CI, 16.4 to 23.6) for low-dose peginterferon alfa-2b, and 31.5% (95% CI, 27.9 to 35.2) for peginterferon alfa-2a. The safety profile was similar among the three groups; serious adverse events were observed in 8.6% to 11.7% of patients. Among the patients with undetectable HCV RNA levels at treatment weeks 4 and 12, a sustained virologic response was achieved in 86.2% and 78.7%, respectively. CONCLUSIONS: In patients infected with HCV genotype 1, the rates of sustained virologic response and tolerability did not differ significantly between the two available peginterferon-ribavirin regimens or between the two doses of peginterferon alfa-2b

Acute hepatitis C: in search of the optimal approach to cure.

Abstract IFN monotherapy for acute hepatitis C can be supported, but a strategy taking into account both baseline (clinical presentation, genotype, HIV coinfection) and early (spontaneous viral decay) virologic response should be developed from carefully conducted, controlled prospective studies comparing a “wait and see strategy”, and different schedules of PEG IFN monotherapy to optimize adherence and costs and to reduce the number needed to treat. The price of the ultimate success of therapy for AVH due to HCV, i.e. a stable and definitive clearance of HCV with no residual liver disease in the long term, should not be paid by a high number of patients who are treated needlessly

Treatment of hepatitis C: critical appraisal of the evidence

Chronic hepatitis C virus infection is currently the most common cause of end stage liver disease worldwide. Although the conclusions of the last National Institutes of Health Consensus Development Conferences on Hepatitis C have recently been published, several important issues remain unanswered. This paper reviews the available data using an evidence-based approach. Current evidence is sufficient to recommend IFN treatment for all patients with acute hepatitis. A later initiation of therapy yields the same likelihood of response as early treatment. A daily induction dose during month 1 is the best treatment option. The current gold standard of efficacy for treatment-naive patients with chronic hepatitis C is the combination of pegylated IFN and ribavirin. The overall sustained viral response rate to these regimens is 54 - 56% following a 48-week course of therapy. Patients with genotype 1 infection will have a 42 - 51% likelihood of response to 48weeks of therapy. Those with genotypes 2 or 3 infection will respond to 24weeks in 78 - 82% of cases. Debate continues regarding the optimal dose and duration of peginterferon (PEG-IFN), not only in patients infected with genotype 2 or 3 but also in those infected with genotype 1. The optimal dose of ribavirin has yet to be determined. Available data show the need to give the highest tolerable doses (1000-1200mg/day) to the difficult-to-treat patients (genotype 1, cirrhotics, obese), although there is a greater likelihood of intolerance. Genotypes 2 and 3 may receive 800mg/day, which is also the most appropriate lower dose for those patients who require dosage modification for anaemia or other side effects. Tolerability and compliance to therapy are still a problem, as approximately 15- 20% of patients within trials and > 25% in clinical practice withdraw from therapy. New PEG-IFNs are more effective than conventional IFN in improving liver histology. Monotherapy with PEG-IFN induces a marked reduction in staging in virological sustained responders, and to a lesser degree in relapsers, but provides no benefit to nonresponders after 24-48weeks of treatment. The use of maintenance therapy in virological nonresponders aiming to improve histology should be considered experimental and of unproven benefit. Pooling data from the literature suggests a slight preventive effect of IFN on hepatocellular carcinoma development in patients with HCV-related cirrhosis. The magnitude of this effect is low and the observed benefit may be due to spurious associations. The preventive effect is more evident among sustained responders to IFN