RESUMO
<p><b>OBJECTIVE</b>Hepatitis B e antigen (HBeAg) seroconversion and/or hepatitis B surface antigen (HBsAg) clearance are considered as good prognostic indicators of treatment outcome in HBeAg-positive chronic hepatitis B (CHB) patients. While a sustained virological response (SVR) can be achieved by a finite 48-week course of pegylated-interferon alfa-2a (Peg-IFNalpha-2a), it has been suggested that longer-term treatment can improve the rate of SVR. Therefore, the aim of this study was to compare the effects of prolonged and routine Peg-IFNa-2a therapy in patients with HBeAg-positive CHB.</p><p><b>METHODS</b>Eighty-six consecutive patients diagnosed with HBeAg-positive CHB at our hospital between September 2006 and October 2009 were enrolled in the study. The patients were randomly assigned to receive Peg-IFNa-2a (180 mug once weekly) for either 48 weeks (routine therapy group, n = 53) or 72 weeks (prolonged therapy group, n = 33). Serum samples were collected from each patient every three months until the end of the 24-week follow-up, and standard viral and biochemical tests were carried out. Relapse was defined as HBV DNA concentrations more than 105 copies/mL or an HBeAg-positive test at the end of the 24-week follow-up. Chi-squared test and the t-test were used to determine the significance of intergroup differences. Logistic regression analysis was employed to determine the correlation of outcome parameters to treatment duration, expressed as odds ratio (OR) with 95% confidence interval (CI).</p><p><b>RESULTS</b>The two treatment groups were similar at baseline (pre-treatment) in demographic data, sex ratio, age, alanine aminotransferase (ALT) level, HBV DNA load, and semi-quantitative level of HBeAg (s/co) (all, P more than 0.05). At the end of the 24-week follow-up, there were significant differences between the 48-week treatment group and the 72-week treatment group in patients with HBV DNA negativity (62.3% vs. 97.0%, x2 = 13.273, P = 0.000), HBeAg seroconversion (39.6% vs. 57.6%, x2 = 6.765, P = 0.009), HBsAg clearance (15.1% vs. 36.4%, x2 = 5.155, P = 0.023), and relapse (58.5% vs. 33.3%, x2 = 6.713, P = 0.010). Logistic regression analysis indicated that therapy duration was correlated to HBeAg clearance (OR = 3.702, 95% CI: 1.225 to 11.188) and male sex (OR = 3.005, 95% CI: 1.038 to 8.696) but not to HBeAg level at baseline (OR = 0.999, 95% CI: 0.998 to 1.000) or age (OR = 0.902, 95% CI: 0.839 to 0.970).</p><p><b>CONCLUSION</b>In this single-center cohort study, superior therapeutic benefit was achieved by extending the Peg-IFNa-2a therapy out to 72 weeks for patients with HBeAg-positive CHB. The prolonged duration therapy produced a higher HBsAg loss ratio, HBeAg seroconversion ratio, HBV DNA negativity ratio, and a lower relapse ratio. Furthermore, HBeAg clearance was positively correlated with duration and male sex.</p>