IMMUNE RESPONSE AND ONE-YEAR ANTIBODY PERSISTENCE AFTER A FOURTH DOSE OF A NOVEL HAEMOPHILUS INFLUENZAE TYPE B AND NEISSERIA MENINGITIDIS SEROGROUPS C AND Y-TETANUS TOXOID CONJUGATE VACCINE (HibMenCY) AT 12 TO 15 MONTHS OF AGE
A total of 236 infants received a fourth Haemophilus influenzae type b-Neisseria meningitidis serogroups C and Y-tetanus toxoid conjugate vaccine (HibMenCY) dose at 12 to 15 months. One month later, the proportion with anti–PRP antibody ≥1.0 μg/mL and bactericidal titers ≥1:8 to MenC and MenY was 98.9%, 96.9%, and 95.4%, respectively. One year later, anti-PRP concentrations ≥0.15 μg/mL, and MenC and MenY bactericidal titers ≥1:8 persisted in 100%, 96.6%, and 83.8%, respectively. The safety profile of HibMenCY was comparable to Hib.