Safety and immunogenicity of a heptavalent pneumococcal conjugate vaccine in infants.
OBJECTIVE
To evaluate the safety and immunogenicity of two lots of a heptavalent Streptococcus pneumoniae conjugate vaccine (PCV) containing seven capsular polysaccharide serotypes (4, 6B, 9V, 14, 18C, 19F, and 23F) conjugated to the outer membrane complex of Neisseria meningitidis serogroup B (OMPC) and administered to infants at 2, 4, 6, and 12 months of age.


METHODS
One hundred twenty infants were randomly assigned to concurrently receive PCV-OMPC and one of two Haemophilus influenzae type b (Hib) conjugate-DTwP combination vaccines: (1) Hib with a heterologous protein carrier (CRM(197), TETRAMUNE, Group 1) or (2) an experimental Hib-hepatitis b combination vaccine with the homologous carrier (OMPC, Group 2). All infants in Groups 1 and 2 received PCV-OMPC (lot 1) at 12 months of age. Another separate group of 120 infants (Group 3) received a different lot of PCV-OMPC concurrently with Hib-CRM(197) (TETRAMUNE) at 2, 4, and 6 months of age and then were randomized to receive either PCV-OMPC or a 23-valent polysaccharide (PS) pneumococcal vaccine at 12 months of age.


RESULTS
Each PCV-OMPC lot was generally well tolerated and no vaccine-related serious adverse events were reported. Following the primary series, serotype-specific anti-pneumococcal geometric mean concentrations (GMC) were highest for serotypes 14, 19F, and 4 and lowest for serotypes 6B and 23F. GMC and seroconversion rates in Group 3 (lot 2) were lower than in Group 1 (lot 1) for serotypes 6B, 14, 18C, and 23F. Antibody responses to serotypes 6B, 14, and 18C were significantly lower in Group 2 compared to Group 1. Following a booster dose of PCV-OMPC at 12 months of age, each lot was immunogenic with at least a 5-10-fold increase in antibody levels, and responses were significantly higher among those who received the PS vaccine.


CONCLUSIONS
PCV-OMPC is generally safe in infants, displays variable immune response by serotype, and concomitant receipt of Hib vaccine with homologous carrier may impact on its immunogenicity.
Zangwill
Kenneth M
KM
UCLA Center for Vaccine Research, Harbor-UCLA Medical Center, Liu Research Building, 1124 W. Carson Street, Torrance, CA 90502, USA. kzangwill@rei.edu
Greenberg
David P
DP
Chiu
Chung-Yin
CY
Mendelman
Paul
P
Wong
Victor K
VK
Chang
Swei-Ju
SJ
Partridge
Susan
S
Ward
Joel I
JI
D006192:Haemophilus Infections / Q000276:immunology*; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007117:Immunization, Secondary; D007223:Infant; D022401:Meningococcal Vaccines / Q000009:adverse effects / Q000627:therapeutic use*; D011008:Pneumococcal Infections / Q000276:immunology*; D022242:Pneumococcal Vaccines / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D018074:Vaccines, Conjugate / Q000009:adverse effects / Q000627:therapeutic use*
D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022401:Meningococcal Vaccines; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate