3.1
Peginterferon alfa-2a (Pegasys, Roche) has UK marketing authorisation for the treatment of HBeAg-positive or HBeAg-negative chronic hepatitis B in adults with compensated liver disease and evidence of viral replication, increased ALT and histologically verified liver inflammation and/or fibrosis. Peginterferons are formed by attaching strands of polyethylene glycol (PEG) to the interferon molecules. This slows the rate of absorption and excretion of interferon, reducing the fluctuations in serum level that occur with unmodified interferon. Peginterferons are administered once a week, compared with 3 or more times a week for the unmodified form.