Three-year antibody persistence and safety after a single dose of combined haemophilus influenzae type b (Hib)-Neisseria meningitidis serogroup C-tetanus toxoid conjugate vaccine in Hib-primed toddlers.
BACKGROUND
Persistence of seroprotective bactericidal antibody titers is important for long-term protection against meningococcal serogroup C disease in young children. Antibody persistence values were determined in children up to 3 years after vaccination with a single dose of the combined Haemophilus influenzae type b (Hib)-Neisseria meningitidis serogroup C (MenC)-tetanus toxoid (TT) conjugate vaccine (Hib-MenC-TT; www.ClinicalTrials.gov: NCT00326118).


METHODS
The children had been randomized at ages 12-18 months to receive either 1 dose of Hib-MenC-TT (Hib-MenC group) or separately administered Hib-TT conjugate vaccine and MenC-CRM197 (MCC) vaccine (Hib plus MCC group). All children had been primed in infancy with a Hib vaccine. Antibodies against MenC were measured by a serum bactericidal assay using rabbit complement (rSBA-MenC) and antibodies against Hib polyribosylribitol phosphate were assessed by enzyme-linked immunosorbent assay.


RESULTS
The rSBA-MenC titers ≥1:8 were demonstrated 3 years after vaccination in 64.2% and 53.2% of participants in the Hib-MenC group and in the Hib plus MCC group, respectively. Antipolyribosylribitol phosphate concentrations ≥0.15 µg/mL persisted in >98% of participants in both groups. The rSBA-MenC geometric mean titers and antipolyribosylribitol phosphate geometric mean concentrations remained higher 3 years after vaccination than before vaccination. No serious adverse events assessed by the investigator as being related to vaccination were reported.


CONCLUSIONS
In this antibody persistence study of Hib-primed but MenC-naïve toddlers who received a single dose of Hib-MenC-TT, protective antibody levels against Hib and MenC were maintained in the majority of children 3 years after vaccination.
National Centre for Immunisation Research and Surveillance (NCIRS), The Children's Hospital at Westmead, Sydney, Australia.
Robert
R
Booy
Peter
P
Richmond
Terry
T
Nolan
Jodie
J
McVernon
Helen
H
Marshall
Michael
M
Nissen
Graham
G
Reynolds
John B
JB
Ziegler
Tanya
T
Stoney
Leon
L
Heron
Stephen
S
Lambert
Narcisa
N
Mesaros
Kavitha
K
Peddiraju
Jacqueline M
JM
Miller
D000907:Antibodies, Bacterial / Q000097:blood; D002675:Child, Preschool; D005260:Female; D018073:Haemophilus Vaccines / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology; D006801:Humans; D007114:Immunization; D008297:Male; D013745:Tetanus Toxoid / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology
D000907:Antibodies, Bacterial; D018073:Haemophilus Vaccines; C527605:Hib-MenCY-TT vaccine; D013745:Tetanus Toxoid; D018074:Vaccines, Conjugate