Immunogenicity, safety and reactogenicity of a mammalian cell-culture-derived influenza vaccine in healthy children and adolescents three to seventeen years of age.
BACKGROUND
The safety and immunogenicity of the cell-culture-derived seasonal trivalent influenza vaccine ([CCIV]; Optaflu) has been reported previously in adults and the elderly. In this study, we compared the safety, reactogenicity and immunogenicity of CCIV with a conventional egg-derived trivalent influenza vaccine (TIV) in a healthy pediatric population.


METHODS
A total of 3604 subjects were randomized to receive 2 doses of CCIV or TIV (3-8 years, n = 2630) at a 28-day interval or a single vaccination (9-17 years, n = 974). Antibody levels on days 1, 29 and 50 were measured by hemaglutination inhibition assay using egg-derived and cell-derived test antigens. Adverse reactions were solicited via memory aids for 7 days after each injection, and unsolicited adverse events/serious adverse events were collected for 6 months postvaccination.


RESULTS
Noninferiority of CCIV versus TIV was demonstrated for most immunogenicity measures, particularly by using cell-derived antigen in the hemaglutination inhibition assay. In 3- to 8-year-olds (the primary objective), both CCIV and TIV met all 3 Committee for Medicinal Products for Human Use immunogenicity criteria for A/H1N1 and A/H3N2 strains. Lower immune responses were observed against the B strain, fulfilling Committee for Medicinal Products for Human Use criteria only for geometric mean ratio (TIV, CCIV) and seroconversion rate (TIV, CCIV [cell-derived antigen]). Both CCIV and TIV were safe and well tolerated, with no differences in local and systemic solicited reactions or in unsolicited adverse events/serious adverse events.


CONCLUSIONS
CCIV produced in mammalian cell culture is a safe, well-tolerated and immunogenic alternative to conventional egg-derived influenza vaccines for children and adolescents.
University of Tampere Medical School, Tampere, Finland. timo.versikari@uta.fi .
Timo
T
Vesikari
Stan L
SL
Block
Fernando
F
Guerra
Maria
M
Lattanzi
Sandra
S
Holmes
Allen
A
Izu
Nicolaos
N
Gaitatzis
Anne Katrin
AK
Hilbert
Nicola
N
Groth
D000293:Adolescent; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002460:Cell Line; D002642:Chick Embryo; D002648:Child; D002675:Child, Preschool; D004311:Double-Blind Method; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology*; D009981:Influenza B virus / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D016896:Treatment Outcome; D022223:Vaccines, Subunit / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology
D000914:Antibodies, Viral; D007252:Influenza Vaccines; D022223:Vaccines, Subunit