title: Immune response, antibody persistence, and safety of a single dose of the quadrivalent meningococcal serogroups A, C, W-135, and Y tetanus toxoid conjugate vaccine in adolescents and adults: results of an open, randomised, controlled study.
abstract: BACKGROUND
  The best strategy to protect individuals against meningococcal disease is to immunize against multiple serogroups. Immunogenicity, antibody persistence, and safety of the EU-licensed meningococcal ACWY-tetanus toxoid conjugate vaccine (MenACWY-TT) were evaluated in healthy participants aged 11-55 years from the Philippines and Saudi Arabia.
  
  
  METHODS
  In this phase IIb, open, controlled study, 500 participants were randomised (3:1) to receive one dose of MenACWY-TT or a licensed meningococcal polysaccharide vaccine (Men-PS). Functional antibody responses against meningococcal serogroups A, C, W-135, and Y were assessed by a serum bactericidal antibody assay using rabbit complement (rSBA) at Month 0, Month 1, Year 1, Year 2, and Year 3. Vaccine response was defined as an rSBA titre ≥32 at Month 1 in participants who were seronegative (rSBA titre <8) pre-vaccination and as at least a four-fold increase in titre in participants who were seropositive pre-vaccination. Solicited symptoms were recorded up to Day 4, safety outcomes up to Month 6, and serious adverse events related to vaccination up to Year 3.
  
  
  RESULTS
  Pre-specified criteria for non-inferiority of MenACWY-TT versus Men-PS were met in terms of rSBA vaccine response and incidence of grade 3 general symptoms. At Month 1, 82.7%-96.3% of MenACWY-TT and 69.7%-91.7% in Men-PS recipients had a vaccine response for each serogroup. At Year 3, ≥99.1% and ≥92.9% of MenACWY-TT recipients retained rSBA titres ≥8 and ≥128, respectively, as compared to ≥86.7% and ≥80.0% in the Men-PS group. Both vaccines had a clinically acceptable safety profile, although injection site redness and swelling were more frequent in MenACWY-TT recipients.
  
  
  CONCLUSIONS
  These results suggest that MenACWY-TT could protect adolescents and adults against meningococcal disease up to three years post-vaccination.
  
  
  BACKGROUND
  This study is registered at http://www.clinicaltrials.gov/NCT00356369.
authors.affiliation: Research Institute for Tropical Medicine, Muntinlupa City, Philippines.
authors.forename: Charissa
authors.initials: C
authors.lastname: Borja-Tabora
authors.forename: Cecilia
authors.initials: C
authors.lastname: Montalban
authors.forename: Ziad A
authors.initials: ZA
authors.lastname: Memish
authors.forename: Marie
authors.initials: M
authors.lastname: Van der Wielen
authors.forename: Veronique
authors.initials: V
authors.lastname: Bianco
authors.forename: Dominique
authors.initials: D
authors.lastname: Boutriau
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Miller
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D032541:Mass Vaccination / Q000706:statistics & numerical data; D022401:Meningococcal Vaccines / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology; D008875:Middle Aged; D010679:Philippines; D012529:Saudi Arabia
chemical_list: D000907:Antibodies, Bacterial; D022401:Meningococcal Vaccines; C576777:tetravalent meningococcal serogroups A, C, W-135 and Y tetanus toxoid conjugate vaccine