title: Long-term persistence of humoral and cellular immune responses induced by an AS03A-adjuvanted H1N1 2009 influenza vaccine: an open-label, randomized study in adults aged 18-60 years and older.
abstract: This manuscript presents data on the persistence of Hemagglutination Inhibition (HI) immune response against the A/California/7/2009 strain, six and 12 mo after adults received one dose (n = 138) or two doses (n = 102; 21 d apart) of a 3.75 µg Hemagglutinin antigen AS03-adjuvanted H1N1 2009 vaccine (NCT00968526). Two hundred forty subjects (18-60 y: 120;>60 y: 120) were vaccinated. Immunogenicity end points were based on the European licensure criteria for pandemic influenza vaccines. Exploratory analyses assessed the cell-mediated immune response (CMI) up to Month 12 and the influence of previous influenza vaccination on persistence of immune response. At Month 6, the CHMP criteria were met in subjects aged 18-60 y who received one or two vaccine doses and in subjects aged>60 y who received two vaccine doses. At Month 12, the CHMP criteria were met only in subjects aged 18-60 y who received two vaccine doses. Persistence of HI immune response against the vaccine strain was higher in subjects without prior influenza vaccination. Exploratory analyses showed that two doses of the H1N1 2009 vaccine induced persistence of H1N1-specific CD4+ T cells up to Month 6 and memory B cells up to Month 12. In conclusion, HI immune responses persisted up to 12 mo after vaccination with one-dose and two-dose regimens of the AS03-adjuvanted 3.75 µg HA H1N1 2009 pandemic influenza vaccine, although not all three CHMP guidance criteria for both groups were met at Month 6 and Month 12. The CD4+ T cell and B cell responses also persisted up to Month 12.
authors.affiliation: Vaccine and Infectious Disease Institute; Centre for the Evaluation of Vaccination; University of Antwerp; Antwerp, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Van Damme
authors.forename: Froukje
authors.initials: F
authors.lastname: Kafeja
authors.forename: Vinod
authors.initials: V
authors.lastname: Bambure
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Hanon
authors.forename: Philippe
authors.initials: P
authors.lastname: Moris
authors.forename: François
authors.initials: F
authors.lastname: Roman
authors.forename: Paul
authors.initials: P
authors.lastname: Gillard
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D004334:Drug Administration Schedule; D004338:Drug Combinations; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007111:Immunity, Cellular / Q000276:immunology; D007156:Immunologic Memory / Q000276:immunology; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D008297:Male; D008875:Middle Aged; D011136:Polysorbates / Q000008:administration & dosage; D013185:Squalene / Q000008:administration & dosage / Q000276:immunology*; D014611:Vaccination; D055815:Young Adult; D024502:alpha-Tocopherol / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D004338:Drug Combinations; D007252:Influenza Vaccines; D011136:Polysorbates; D013185:Squalene; C550253:AS03 adjuvant; D024502:alpha-Tocopherol
keywords: H1N1; cellular immune response; long-term; persistence