Immunogenicity and safety of MF59-adjuvanted H5N1 influenza vaccine from infancy to adolescence.
OBJECTIVE
This study evaluated the immunogenicity, safety, and tolerability of a MF59-adjuvanted H5N1 vaccine in a population 6 months through 17 years of age.


METHODS
Healthy subjects 6 to <36 months, 3 to <9 months, and 9 to <18 years of age were assigned randomly to receive 2 doses of either a MF59-adjuvanted H5N1 vaccine (7.5 μg/dose) or a MF59-adjuvanted trivalent seasonal influenza control vaccine (15 μg/dose for each antigen). Immunogenicity against the A/Vietnam/1194/2004-like vaccine strain was measured before and 3 weeks after the 2-dose primary series, through hemagglutination inhibition (HI), single radial hemolysis (SRH), and microneutralization. Local and systemic reactions were recorded.


RESULTS
A total of 335 subjects received the H5N1 vaccine, and 137 subjects received the seasonal vaccine. Rates of seroprotection (HI titer of ≥40) against the H5N1 vaccine antigen were 97% for children 6 to 36 months and 3 to 9 years of age and 89% for older children. All subjects seroconverted in the SRH assay. Microneutralization titers of ≥40 were achieved by 99% of subjects, and ≥98% of subjects, respectively. Local reactions, particularly injection site pain in older children, were common, generally mild to moderate in nature, and transient and resolved spontaneously. Up to 5% of participants. There were no vaccine-related serious adverse events in either group.


CONCLUSIONS
In this pediatric population, MF59-adjuvanted H5N1 vaccine was highly immunogenic, had a good safety profile, reactogenicity comparable with that of an adjuvanted seasonal influenza control vaccine.
Vesikari
Timo
T
University of Tampere, School of Medicine, Vaccine Research Center, FM3, Biokatu 10, 33520 Tampere, Finland. timo.vesikari@uta.fi
Karvonen
Aino
A
Tilman
Sandrine
S
Borkowski
Astrid
A
Montomoli
Emanuele
E
Banzhoff
Angelika
A
Clemens
Ralf
R
D000276:Adjuvants, Immunologic; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007114:Immunization; D007223:Infant; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000009:adverse effects / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology / Q000517:prevention & control*; D011136:Polysorbates; D013185:Squalene / Q000276:immunology*; D015164:Vaccines, Inactivated
D000276:Adjuvants, Immunologic; D007252:Influenza Vaccines; C089950:MF59 oil emulsion; D011136:Polysorbates; D015164:Vaccines, Inactivated; D013185:Squalene