Safety and long-term humoral immune response in adults after vaccination with an H1N1 2009 pandemic influenza vaccine with or without AS03 adjuvant.
BACKGROUND
In this study (NCT00985088) we evaluated different formulations of an H1N1 2009 pandemic influenza vaccine that deliver various viral hemagglutinin (HA) doses with or without AS03 (a tocopherol-based oil-in-water adjuvant system).


METHODS
A total of 1340 healthy subjects aged ≥18 years were randomized to receive 1 or 2 doses of an adjuvanted (3.75-μg HA/AS03(A) or 1.9-μg HA/AS03(B)) or nonadjuvanted vaccine formulation. Safety and immunogenicity (by hemagglutination-inhibition [HI] assay) after each dose and 6 months after dose 1 are reported here.


RESULTS
A single dose of AS03(A)-adjuvanted 3.75-μg HA H1N1 2009 induced the strongest immune responses in subjects aged 18-64 years (seroprotection rate [SPR], 97.2%; seroconversion rate [SCR], 90.1%) as well as in subjects aged >64 years (SPR, 91.1%; SCR, 78.2%) 21 days after vaccination. Six months after dose 1, subjects who received 2 doses of either the adjuvanted formulation or 1 dose of the adjuvanted 3.75-μg HA formulation continued to meet all Center for Biologics Evaluation and Research and Committee for Medicinal Products for Human Use criteria. All formulations had clinically acceptable safety profiles.


CONCLUSIONS
A single dose of the 3.75-μg HA AS03(A)-adjuvanted H1N1 2009 influenza vaccine was highly immunogenic in both age strata (18-64 and >64 years), inducing long-term persistence of the immune response until at least 6 months after dose 1.
Colchester Research Group, Truro, Nova Scotia, Canada.
Murdo
M
Ferguson
George
G
Risi
Matthew
M
Davis
Eric
E
Sheldon
Mira
M
Baron
Ping
P
Li
Miguel
M
Madariaga
Louis
L
Fries
Olivier
O
Godeaux
David
D
Vaughn
D000276:Adjuvants, Immunologic / Q000008:administration & dosage* / Q000009:adverse effects; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D005221:Fatigue / Q000209:etiology; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006388:Hemagglutinins / Q000276:immunology; D006801:Humans; D056724:Immunity, Humoral; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000009:adverse effects / Q000276:immunology* / Q000592:standards; D007251:Influenza, Human / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D016037:Single-Blind Method; D013997:Time Factors; D024505:Tocopherols / Q000008:administration & dosage* / Q000009:adverse effects; D014611:Vaccination / Q000379:methods; D055815:Young Adult
D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D006388:Hemagglutinins; D007252:Influenza Vaccines; D024505:Tocopherols