Incidence and Predictors of HBsAg Loss After Peginterferon Therapy in HBeAg-Negative Chronic Hepatitis B: A Multicenter, Long-term Follow-up Study

Background. The long-term incidence and factors associated with hepatitis B surface antigen (HBsAg) loss in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) patients receiving peginterferon is rarely reported. Methods. From 2004 to 2016, 233 HBeAg-negative CHB patients who completed 48 weeks of peginterferon treatment from 3 medical centers in Taiwan were retrospectively enrolled. Results. During a median follow-up of 7.4 years, 27 cases achieved HBsAg loss. The cumulative incidences of HBsAg loss and HBsAg seroconversion at 3, 5, 10 years after peginterferon treatment were 4.7%, 9.4%, 14.2%, and 3.5%, 6.4%, 12.5%, respectively, in overall patients, and 15.9%, 29.1%, 37.3%, and 13.1%, 19%, 30.6%, respectively, in patients achieving sustained off-treatment viro-logical response (SVR). By multivariate analysis, age (<35 years; hazard ratio [HR] = 3.742, P = .007), baseline HBsAg levels (<1250 IU/mL; HR = 4.849, P = .002), HBsAg decline at week 24 (>= 1 log; HR = 5.660, P = .002), and achieving SVR (HR = 8.546, P = .006) were predictors of HBsAg loss. After achieving SVR, HBsAg loss rates were higher than 30% in 5 years among patients with either younger age or lower HBsAg at baseline. Conclusions. HBsAg loss rate continues to increase after peginterferon treatment in HBeAg-negative CHB patients with SVR. Age, baseline HBsAg levels, on-treatment HBsAg decline, and achieving SVR are factors associated with long-term HBsAg loss.