Hepatitis B virus genotype B results in better immediate, late and sustained responses to peginterferon-alfa in hepatitis-B-e-antigen-positive patients

Background and Aims: This study investigated outcome predictors in hepatitis-B-e-antigen (HBeAg)-positive chronic hepatitis B patients treated with peginterferon alfa-2a. Methods: A total of 88 HBeAg-positive patients receiving peginterferon alfa-2a for 6months and followed up for at least 24weeks were prospectively analyzed. Precore and core promoter genes of hepatitis B virus (HBV) were sequenced from the serial serum samples of 88 patients. Results: After 24weeks of follow up, 38.6% and 28.4% of patients achieved HBeAg clearance and combined response, respectively. Multivariate analysis disclosed that pretreatment HBeAg sample to cut-off (S/Co) ratio ≤200, alanine aminotransferase>200IU/mL, HBV genotype B and T1846 were independent factors for HBeAg clearance, and HBeAg S/Co ratio≤200 and HBV genotype B were major determinants for combined response. HBeAg S/Co ratio≤10 at week 12 of therapy was the useful factor for treatment response and had a greater power (P=0.012) to predict HBeAg clearance than HBV DNA. Patients with HBeAg clearance had a higher frequency of A1896 mutation at baseline and during therapy than those without HBeAg clearance, and the frequency of A1896 decreased during treatment. During follow up, delayed HBeAg seroconversion and reactivation of HBV after HBeAg clearance were observed in eight non-responders and 20 patients with HBeAg clearance, respectively. HBV genotype B was a significant factor to predict both responses. Conclusions: Pretreatment HBeAg S/Co ratio≤200 and HBV genotype B were major determinants for treatment response to peginterferon. Genotype-B-infected patients had higher probability of delayed HBeAg clearance and sustained response. Rapid decrease of HBeAg titer was useful on treatment predictor. © 2011 Journal of Gastroenterology and Hepatology Foundation and Blackwell Publishing Asia Pty Ltd.