Immunogenicity and safety of a pneumococcal conjugate 7-valent vaccine in infants with sickle cell disease.
OBJECTIVE
To evaluate safety and immunogenicity of the pneumococcal 7-valent conjugate vaccine (PCV7) when administered to infants with sickle cell disease (SCD) at 2, 3, and 4 months of age with a booster dose of a 23-valent pneumococcal polysaccharide vaccine (PS-23) at 15 to 18 months of age.


METHODS
This open-label multicenter study in France enrolled 2-month-old infants with SCD. Blood samples for the determination of antibody concentrations to vaccine serotypes were obtained immediately before and 1 month after the primary immunization, and before and 1 month after the PS-23 booster. Local and systemic reactions were recorded on diary cards.


RESULTS
Of the 51 infants enrolled, 49 received primary immunization and 46 received the booster dose. After primary immunization > or =95% of the subjects had antibody titers > or =0.35 microg/mL for the 7 serotypes. After boosting, geometric mean concentrations were high for all serotypes, ranging from 6.32 microg/mL (serotype 18C) to 29.49 microg/mL (serotype 4). Except for 1 case after administration of the booster dose, all fevers reported were less than 39 degrees C. No vaccine-related serious adverse events were reported.


CONCLUSIONS
PCV7 administered at 2, 3, and 4 months of age in infants with SCD was well-tolerated, highly immunogenic, and primed for immune memory as indicated by the dramatic response to the PS-23 dose administered at 15-18 months in this study. However, the current recommended schedule is to boost with the PCV7 at 12-15 months of age and for these high-risk children, to enlarge the protection with a subsequent PS-23 dose at 2 years of age.
CHI Créteil, France. preinert@club-internet.fr
Philippe
P
Reinert
Malika
M
Benkerrou
Mariane
M
de Montalembert
Emmanuelle
E
Lesprit
Isabelle
I
Abadie
Françoise
F
Bernaudin
Catherine
C
Doit
Edouard
E
Bingen
Robert
R
Tetelboum
Eric
E
Bonnet
D000755:Anemia, Sickle Cell / Q000276:immunology*; D000907:Antibodies, Bacterial / Q000097:blood*; D006450:Hemoglobin SC Disease / Q000276:immunology; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007114:Immunization; D007115:Immunization Schedule; D007117:Immunization, Secondary; D007223:Infant; D022401:Meningococcal Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D011008:Pneumococcal Infections / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D012805:Sickle Cell Trait / Q000276:immunology; D013296:Streptococcus pneumoniae / Q000276:immunology*; D013789:Thalassemia / Q000276:immunology; D016896:Treatment Outcome
D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022401:Meningococcal Vaccines; D022242:Pneumococcal Vaccines