Immunogenicity of a birth dose of hepatitis B vaccine in Kinshasa, Democratic Republic of Congo: a randomized, controlled trial

We aimed to assess the immunogenicity of the hepatitis B birth-dose vaccine (HepB-BD) in addition to the existing hepatitis B vaccine (HepB3) schedule in Kinshasa, Democratic Republic of Congo among HBV-unexposed and HBV-exposed infants. Using an open-label, randomized, controlled design, HBV-unexposed infants were randomized (1:1) to receive the standard HepB3 vaccine series (group U3), or to receive HepB-BD in addition to HepB3 (group U4). A supplemental cohort of HBV-exposed infants (group E4) received HepB-BD and HepB3. We compared the proportion of infants with protective antibodies against HBV (HBV surface antibody ≥ 10 mIU/mL) between groups U3 and U4 and groups U4 and E4 at 12 months of age. Between August 20 and October 9, 2019, we enrolled 281 mother/infant dyads; 88 (31.3%) returned at 12 months.