The 517 patients randomized to the treatment
arm received 90 micrograms of peginterferon in
weekly injections for 3.5 years. The 533 patients in the control arm underwent the same follow-up and care as the treated patients including liver biopsies, quarterly clinic visits, and blood tests. All patients had advanced liver fibrosis, a gradual scarring of the liver that puts patients at risk for progressive liver disease.