Incidence and predictors of HBsAg loss in treatment-naïve children with immune-tolerant chronic hepatitis B after antiviral therapy

Background There are no established recommendations for the most suitable treatment of children with immune-tolerant chronic hepatitis B (CHB). Aims To evaluate the clinical outcome of combination therapy among treatment-naïve children with immune-tolerant CHB. Methods We retrospectively identified pediatric patients who were diagnosed with immune-tolerant CHB and who received combination therapy with interferon-alpha (IFN-α) or peginterferon-alpha-2a (Peg-IFN-α-2a) plus entecavir at Hunan Children’s Hospital between August 2014 and April 2023. A total of 106 patients were ultimately enrolled in the study. Complete clinical data were collected for all the enrolled patients. The associations between baseline characteristics and HBsAg loss were assessed using Cox proportional hazards regression. Restricted cubic spline (RCS) plots were constructed to portray the association between HBsAg loss and patient age. Results After a median follow-up of 87 weeks, 23.5% (25/106) of the participants achieved sustained HBsAg loss, with a cumulative incidence of 44.9%. Proportional hazard regression indicated a significant association between achieving HBsAg loss and age, HBsAg level, and HBsAb level at baseline. The RCS plots suggested that, for pediatric patients, initiating antiviral therapy for immune-tolerant CHB might be most beneficial when they are less than 5 years old. Seventy-five (70.8%) patients experienced adverse events (AEs) following interferon therapy, with no severe AEs leading to treatment discontinuation. Conclusion The combination therapy led to favorable clinical outcomes for children with immune-tolerant CHB. Moreover, young age and low HBsAg and high HBsAb levels at baseline are predictors of a clinical cure.