Immunogenicity and Safety of an Inactivated Enterovirus 71 Vaccine Administered Simultaneously With Hepatitis B Vaccine and Group A Meningococcal Polysaccharide Vaccine: A Phase 4, Open-Label, Single-Center, Randomized, Noninferiority Trial

Background This study tested the hypothesis that the immunogenicity and safety of the simultaneous administration of enterovirus 71 (EV71) vaccine (dose 1) with recombinant hepatitis B vaccine (HepB) on day 1 and EV71 vaccine (dose 2) with group A meningococcal polysaccharide vaccine (MenA) on day 30 is not inferior to separate administration of each vaccine. Methods The study was designed as a randomized, open-label, noninferiority trial. A total of 775 healthy infants aged 6 months were randomly assigned in a ratio of 1:1:1 to receive simultaneous administration of EV71 vaccine (dose 1) and HepB on day 1 and EV71 vaccine (dose 2) and MenA on day 30 (the SI group); administration of doses 1 and 2 of EV71 vaccine on days 1 and 30, respectively (the SE1 group); or administration of HepB and MenA on days 1 and 30, respectively (the SE2 group). Results According to the per protocol set, antibody responses against EV71, hepatitis B virus (HBV), and group A meningococcal polysaccharide were similar regardless of administration schedule. With the non-inferiority margin setting at 10%, the seroconversion rates of the three pathogens in the SI group (100% [98.25, 100], 44.84% [38.20, 51.63] and 27.83% [21.91, 34.38]) were not inferior to those in SE1 or SE2 group (100% [98.31, 100], 44.35% [37.82, 51.02] and 29.17% [23.20, 35.72], respectively). Frequencies of adverse reactions to each vaccination regimen were comparable (60.62% in the SI group vs 52.33% in the SE1 group and 56.98% in the SE2 group; P = .16). Conclusions Simultaneous administration of combined EV71 vaccine with HepB and MenA has noninferior immunogenicity and safety, compared with separate administration of these vaccines. Clinical Trials Registration NCT03274102. We proved that simultaneous administration of enterovirus 71 vaccine with hepatitis B vaccine and group Ameningococcal polysaccharide vaccine has noninferior immunogenicity and safety, compared with separate administration of each vaccine, through a phase 4, open-label, single-center, randomized, noninferiority clinical trial.