High rate of functional cure in infants with chronic hepatitis B following a definite duration of antiviral treatment

Background: Data on antiviral treatment for infants with chronic hepatitis B (CHB) are limited. This study is aimed to investigate whether and how antiviral treatment can achieve a functional cure in infants with CHB. Methods: This real-world study enrolled 21 infants (9 boys and 12 girls) with active hepatitis B e antigen (HBeAg)-positive CHB from the Fifth Medical Center of Chinese PLA General Hospital, who were perinatally infected with hepatitis B virus (HBV) by mother-to-child transmission. The median baseline age was 9 months. Twenty-one cases initially received Lamivudine (LAM) monotherapy, and interferon-α (IFN-α) treatment was added when they were more than 12 months old. The virological responses, functional cure, and treatment safety were analyzed for 36 months (treatment plus follow-up visit duration). Results: All 21 infants with CHB (baseline median HBV DNA was 7.75 log 10 IU/mL) had full viral suppression on antiviral treatment, and the median time taken for undetectable HBV DNA was 6 months (range: 1–19 months). Correspondingly, the median time taken for HBeAg seroconversion was 7 months (range: 3–18 months) for 20 infants, and one case did not obtain HBeAg seroconversion; 19 of the 21 infants achieved a functional cure through a median time of 9 months (range: 4–27 months) since baseline. Two infants did not achieve a functional cure at the 36-month endpoint, but they achieved undetectable HBV DNA, and one of them had HBeAg seroconversion. Flu-like symptoms associated with IFN-α treatment were the common side effects; however, no serious adverse events were observed. Conclusion: Our findings indicate that under 1-year-old infants with active CHB can achieve a significantly high probability of a functional cure when they receive a definite duration of antiviral treatment using LAM add-on IFN-α therapy.