Functional cure is associated with younger age in children undergoing antiviral treatment for active chronic hepatitis B.

BACKGROUND AND AIMS: Functional cure is difficult to achieve using current antiviral therapies; moreover, limited data are available regarding treatment outcomes in children. This retrospective study aimed to assess the frequency of functional cure among children undergoing antiviral treatment for active chronic hepatitis B (CHB).

METHODS: A total of 372 children aged 1-16 years, with active CHB were enrolled and underwent either nucleos(t)ide analog monotherapy or combination therapy with interferon-α (IFN-α) for 24-36 months. All children attended follow-up visits every 3 months. Functional cure was defined as evidence of hepatitis B virus (HBV) DNA loss, circulating hepatitis B e antigen (HBeAg) loss/seroconversion, and hepatitis B surface antigen (HBsAg) loss.

RESULTS: After 36 months of antiviral treatment and/or follow-up visits, children with CHB aged 1- < 7 years exhibited higher rates of HBV DNA clearance, HBeAg seroconversion, and HBsAg loss than CHB children ≥ 7-16 years of age (93.75% versus [vs.] 86.21% [p < 0.0001]; 79.30% vs. 51.72% [p < 0.0001]; and 50.78% vs. 12.93% [p < 0.0001], respectively). Longitudinal investigation revealed more rapid dynamic reduction in HBV DNA, HBeAg, and HBsAg levels in children aged 1-7 years than in those aged ≥ 7-16 years with CHB. According to further age-stratified analysis, HBsAg loss rates were successively decreased in children with CHB who were 1- < 3, 3- < 7, 7- < 12, and 12-16 years of age (62.61% vs. 41.13% vs. 25.45% vs. 1.64%, respectively; p < 0.0001) at 36 months. In addition, baseline HBsAg level < 1,500 IU/mL was found to favor disease cure among these pediatric patients. No serious adverse events were observed throughout the study period.

CONCLUSION: Results of the present study demonstrated that children aged 1- < 7 years, with active CHB can achieve a high functional cure rate by undergoing antiviral therapy compared to those aged ≥ 7 years, who undergo antiviral therapy. These data support the use of antiviral treatment at an early age in children with CHB. However, future prospectively randomized controlled trials are necessary to validate the findings of this study.