title: Immunogenicity and Safety of a Trivalent Inactivated Influenza Vaccine in Children 6 Months to 17 Years of Age, Previously Vaccinated with an AS03-Adjuvanted A(H1N1)Pdm09 Vaccine: Two Open-label, Randomized Trials.
abstract: BACKGROUND
  During the influenza pandemic 2009-2010, an AS03-adjuvanted A(H1N1)pdm09 vaccine was used extensively in children 6 months of age and older, and during the 2010-2011 influenza season, the A(H1N1)pdm09 strain was included in the seasonal trivalent inactivated influenza vaccine (TIV) without adjuvant. We evaluated the immunogenicity and safety of TIV in children previously vaccinated with the AS03-adjuvanted A(H1N1)pdm09 vaccine.
  
  
  METHODS
  Healthy children were randomized (1:1) to receive TIV or a control vaccine. Children were aged 6 months to 9 years (n = 154) and adolescents 10-17 years (n = 77) when they received AS03-adjuvanted A(H1N1)pdm09 vaccine at least 6 months before study enrolment. Hemagglutination inhibition (HI) and neutralizing antibody responses against the A(H1N1)pdm09 strain were evaluated before (day 0) and at day 28 and month 6 after study vaccination. Reactogenicity was assessed during the 7 day postvaccination period, and safety was assessed for 6 months.
  
  
  RESULTS
  At day 0, >93.9% of all children had HI titers ≥1:40 for the A(H1N1)pdm09 strain, which increased to 100% at both day 28 and month 6 in the TIV group. Between days 0 and 28, HI antibody geometric mean titers against A(H1N1)pdm09 increased by 9-fold and 4-fold in children 6 months to 9 years of age and 10-17 years of age, respectively.
  
  
  CONCLUSIONS
  AS03-adjuvanted A(H1N1)pdm09 vaccine-induced robust immune responses in children that persisted into the next season, yet were still boosted by TIV containing A(H1N1)pdm09. The reactogenicity and safety profile of TIV did not appear compromised by prior receipt of AS03-adjuvanted A(H1N1)pdm09 vaccine.
authors.affiliation: From the *Vaccine Research Center, University of Tampere Medical School, Tampere, Finland; †Department of Infectious Disease Control, Municipal Public Health Service (GGD) Rotterdam-Rijnmond, Rotterdam, The Netherlands; ‡School of Health Science, Blekinge Institute of Technology, Karlskrona, Sweden; §Childhood Obesity Unit, Skåne University Hospital, Malmö, Sweden; ¶Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden; ‖Department of Clinical Sciences, Umeå University, Umeå, Sweden; **Quanticate, Bangalore, India; ††GSK Vaccines, Wavre, Belgium; ‡‡GSK Vaccines, Rixensart, Belgium; and §§GSK Vaccines, King of Prussia, PA.
authors.forename: Timo
authors.initials: T
authors.lastname: Vesikari
authors.forename: Jan Hendrik
authors.initials: JH
authors.lastname: Richardus
authors.forename: Johan
authors.initials: J
authors.lastname: Berglund
authors.forename: Tiina
authors.initials: T
authors.lastname: Korhonen
authors.forename: Carl-Erik
authors.initials: CE
authors.lastname: Flodmark
authors.forename: Ann
authors.initials: A
authors.lastname: Lindstrand
authors.forename: Sven Arne
authors.initials: SA
authors.lastname: Silfverdal
authors.forename: Vinod
authors.initials: V
authors.lastname: Bambure
authors.forename: Adrian
authors.initials: A
authors.lastname: Caplanusi
authors.forename: Ilse
authors.initials: I
authors.lastname: Dieussaert
authors.forename: Sumita
authors.initials: S
authors.lastname: Roy-Ghanta
authors.forename: David W
authors.initials: DW
authors.lastname: Vaughn
mesh_terms: D000293:Adolescent; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D002648:Child; D002675:Child, Preschool; D004338:Drug Combinations; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007223:Infant; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D011136:Polysorbates / Q000008:administration & dosage; D013185:Squalene / Q000008:administration & dosage; D016896:Treatment Outcome; D014611:Vaccination / Q000009:adverse effects* / Q000379:methods*; D024502:alpha-Tocopherol / Q000008:administration & dosage
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D004338:Drug Combinations; D007252:Influenza Vaccines; D011136:Polysorbates; D013185:Squalene; C550253:AS03 adjuvant; D024502:alpha-Tocopherol