title: Safety, immunogenicity, and immune memory of a novel meningococcal (groups A, C, Y, and W-135) polysaccharide diphtheria toxoid conjugate vaccine (MCV-4) in healthy adolescents.
abstract: OBJECTIVE
  A meningococcal (groups A, C, Y, and W-135) polysaccharide diphtheria toxoid conjugate vaccine (MCV-4; Menactra; Sanofi Pasteur Inc, Swiftwater, Pa) was developed to improve the profile of currently licensed products. The objective of this study was to compare the tolerability, immunogenicity, and immune memory of MCV-4 with those of a quadrivalent polysaccharide vaccine (PSV-4; Menomune A/C/Y/W-135; Sanofi Pasteur Inc).
  
  
  METHODS
  A randomized, double-blind trial was performed at 11 clinical centers in the United States. The vaccine MCV-4 or PSV-4 was administered to 881 healthy 11- to 18-year-olds. Sera were collected prevaccination and 28 days postvaccination. Three-year follow-up and booster vaccination with MCV-4 were performed in a participant subset from each group and a control group.
  
  
  METHODS
  Proportion of participants with a 4-fold or greater increase in serum bactericidal antibody against each serogroup 28 days after initial vaccination, geometric mean serum bactericidal antibody titers, and safety assessments.
  
  
  RESULTS
  Both vaccines were well tolerated; most reactions were mild. More MCV-4 recipients reported solicited local reactions (68.9%) than PSV-4 recipients (30.2%). Both MCV-4 and PSV-4 were highly immunogenic; similar proportions of participants had 4-fold or greater increases in serum bactericidal antibody (range, 80.1%-96.7%) to the 4 serogroups. Three-year follow-up showed persistence of serum bactericidal antibody and booster responses to MCV-4 consistent with immune memory in participants previously vaccinated with MCV-4, but not in those who had previously received PSV-4.
  
  
  CONCLUSIONS
  The vaccine MCV-4 was well tolerated and highly immunogenic. Persistence of bactericidal activity with MCV-4, but not PSV-4, was evident 3 years after the initial immunization. Booster response was demonstrated after a second vaccination with MCV-4.
authors.affiliation: School of Medicine, Emory University, 2015 Uppergate Drive NE, Atlanta, GA 30322, USA. hkeyser@emory.edu
authors.forename: Harry
authors.initials: H
authors.lastname: Keyserling
authors.forename: Thomas
authors.initials: T
authors.lastname: Papa
authors.forename: Katalin
authors.initials: K
authors.lastname: Koranyi
authors.forename: Robert
authors.initials: R
authors.lastname: Ryall
authors.forename: Ehab
authors.initials: E
authors.lastname: Bassily
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Bybel
authors.forename: Kevin
authors.initials: K
authors.lastname: Sullivan
authors.forename: Gregory
authors.initials: G
authors.lastname: Gilmet
authors.forename: Al
authors.initials: A
authors.lastname: Reinhardt
mesh_terms: D000293:Adolescent; D000907:Antibodies, Bacterial / Q000032:analysis; D002648:Child; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D008297:Male; D022401:Meningococcal Vaccines / Q000009:adverse effects* / Q000276:immunology*; D009345:Neisseria meningitidis / Q000276:immunology; D015610:Serum Bactericidal Test; D018074:Vaccines, Conjugate / Q000009:adverse effects / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D022401:Meningococcal Vaccines; D018074:Vaccines, Conjugate