Peginterferon therapy for chronic hepatitis B: one size fits all?
- Correspondence to Dr Henry Lik-Yuen Chan, Department of Medicine and Therapeutics and Institute of Digestive Disease, The Chinese University of Hong Kong, 9/F Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China;
- Received 16 July 2012
- Accepted 31 July 2012
- Published Online First 1 September 2012
Interferon: a finite course of antiviral treatment
The disease of chronic hepatitis B hinges on a balance between the virus and the host immune system. Clearance of hepatitis B virus (HBV) relies on the host immunity. On the other hand, liver necroinflammation and cirrhosis occurs when there is persistent, yet unsuccessful, immune clearance of the virus.1 Interferon is the first registered drug for the treatment of chronic hepatitis B. It is an immune modulator with weak antiviral property. Its main function is to augment the host immune clearance of the virus. Hence interferon works best when the host is in the immune clearance phase with elevated liver enzymes and low HBV DNA.2 One major advantage of interferon is the finite treatment course, which can potentially lead to sustained remission of disease in the subsequent decades.3 Long-term follow-up studies have confirmed a reduction in risk of liver-related complications, hepatocellular carcinoma and liver-related mortality among sustained interferon responders.4 ,5
Interferon treatment: how long is enough?
Since the mid-1980s, the standard duration of interferon has been 16–24 weeks. Although some evidence suggested that prolonged interferon to 32 weeks might improve the response,6 24 weeks was still the recommended duration for hepatitis B e antigen (HBeAg)-positive patients in regional guidelines.7 ,8 Early studies of peginterferon have used 32-week peginterferon, with or without lamivudine combination, with satisfactory results.9 ,10 In the pivotal of studies of peginterferon, all patients received 48–52 weeks of treatment.11–13 The standard treatment duration of peginterferon for chronic hepatitis B was then set to 48 weeks in both HBeAg-positive and HBeAg-negative patients.7 ,14 The evidence to support the use of 48-week over 24-week peginterferon was only available half a decade after its global registration for this indication.15 In this study (the NEPTUNE study), peginterferon α-2a at a standard dose of 180 mcg/week for 48 weeks was associated with …