title: Cross-clade immunogenicity and antigen-sparing with an AS03(A)-adjuvanted prepandemic influenza vaccine in a Thai population.
abstract: OBJECTIVE
  The present study (NCT00449670) in Asian subjects (18-60 years) evaluated the manufacturing consistency of four formulations of 3.75 mg AS03(A)-adjuvanted H5N1 influenza vaccine, in terms of post-immunization Hemagglutination Inhibition (HI) titers against the A/Vietnam/1194/2004 and A/Indonesia/05/2005 strains. The immunogenicity and safety of the vaccine in the Thai population are reported herein.
  
  
  METHODS
  Subjects were randomized (2:2:2:2.:1:1) between four vaccine groups and two control groups to receive two doses of either the AS03(A)-adjuvanted or non-adjuvanted H5N1 vaccine formulations, 21 days apart. Sera were assayed for HI antibody titers against the two strains.
  
  
  RESULTS
  After the second dose of AS03(A)-adjuvanted vaccine, 94.2% subjects in the H5N1-AS03(A) groups seroconverted and 94.9% subjects were seroprotected against the A/Vietnam/1194/2004 strain. Cross-clade immune response against the A/Indonesia/05/2005 strain was observed. All vaccine formulations had an acceptable safety profile.
  
  
  CONCLUSIONS
  This antigen-sparing AS03(A)-adjuvanted influenza vaccine could be a suitable candidate for combating and mitigating future influenza pandemics.
authors.affiliation: Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. siptc@mahidol.ac.th
authors.forename: Prasert
authors.initials: P
authors.lastname: Thongcharoen
authors.forename: Prasert
authors.initials: P
authors.lastname: Auewarakul
authors.forename: Yanee
authors.initials: Y
authors.lastname: Hutagalung
authors.forename: Gary
authors.initials: G
authors.lastname: Ong
authors.forename: Paul
authors.initials: P
authors.lastname: Gillard
authors.forename: Mamadou
authors.initials: M
authors.lastname: Drame
authors.forename: Hans L
authors.initials: HL
authors.lastname: Bock
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007115:Immunization Schedule; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D058873:Pandemics / Q000517:prevention & control*; D013785:Thailand; D014611:Vaccination; D055815:Young Adult
chemical_list: D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D007252:Influenza Vaccines