Maternal antiviral treatment safeguards infants from hepatitis B transmission in contingencies of delayed immunoprophylaxis.

Background & Aims: Effectiveness of maternal antiviral prophylaxis in mother-to-child transmission of hepatitis B virus (HBV) has been extensively explored in studies where standard immunoprophylaxis is well secured to the newborns. This real-world study aims to test if maternal antiviral prophylaxis can safeguard the newborn when immunoprophylaxis administration was delayed or missed.
Methods: Hepatitis B surface antigen-positive pregnant women were categorized into mothers with HBV DNA levels ≥2 × 10 ⁵ IU/mL receiving nucleos(t)ide analogue during the third trimester; mothers with HBV DNA levels ≥2 × 10 ⁵ IU/mL without antiviral treatment; and those with HBV DNA levels <2 × 10 ⁵ IU/mL without antiviral treatment. The immunoprophylaxis procedure was collected and verified by the delivery medical document and logbook of biological product usage. The primary end point was the rate of chronic HBV infection (CHB) in infants.
Results: From 2011 to 2017, 251 mother-child pairs were enrolled. Among 187 infants of mothers with HBV DNA levels ≥2 × 10 ⁵ IU/mL, none developed CHB when mothers received antiviral treatment, as compared to 13.0% (10/77) of infants born to untreated mothers (P < .001). None of the infants of mothers with HBV DNA levels <2 × 10 ⁵ IU/mL were infected. Stratified by the time of immunoprophylaxis administration after birth, maternal antiviral prophylaxis predominately benefited infants who failed to receive immunoprophylaxis within 24 hours (100% [6/6] vs 0% [0/2], P = .036) and those who received delayed immunoprophylaxis between 2 and 24 hours (18.8% [3/16] vs 0% [0/32], P = .032).
Conclusions: Antiviral prophylaxis in high viraemic mothers is effective in contingencies of missed or delayed neonatal immunoprophylaxis.
(© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)