title: Antibody Persistence at 1 and 4 Years Following a Single Dose of MenAfriVac or Quadrivalent Polysaccharide Vaccine in Healthy Subjects Aged 2-29 Years.
abstract: BACKGROUND
  Mass vaccination campaigns of the population aged 1-29 years with 1 dose of group A meningococcal (MenA) conjugate vaccine (PsA-TT, MenAfriVac) in African meningitis belt countries has resulted in the near-disappearance of MenA. The vaccine was tested in clinical trials in Africa and in India and found to be safe and highly immunogenic compared with the group A component of the licensed quadrivalent polysaccharide vaccine (PsACWY). Antibody persistence in Africa and in India was investigated.
  
  
  METHODS
  A total of 900 subjects aged 2-29 years were followed up for 4 years in Senegal, Mali, and The Gambia (study A). A total of 340 subjects aged 2-10 years were followed up for 1 year in India (study B). In study A, subjects were randomized in a 2:1 ratio, and in study B a 1:1 ratio to receive either PsA-TT or PsACWY. Immunogenicity was evaluated by measuring MenA serum bactericidal antibody (SBA) with rabbit complement and by a group A-specific immunoglobulin G (IgG) enzyme-linked immunosorbent assay.
  
  
  RESULTS
  In both studies, substantial SBA decay was observed at 6 months postvaccination in both vaccine groups, although more marked in the PsACWY group. At 1 year and 4 years (only for study A) postvaccination, SBA titers were relatively sustained in the PsA-TT group, whereas a slight increasing trend, more pronounced among the youngest, was observed in the participants aged <18 years in the PsACWY groups. The SBA titers were significantly higher in the PsA-TT group than in the PsACWY group at any time point, and the majority of subjects in the PsA-TT group had SBA titers ≥128 and group A-specific IgG concentrations ≥2 µg/mL at any point in time in both the African and Indian study populations.
  
  
  CONCLUSIONS
  Four years after vaccination with a single dose of PsA-TT vaccine in Africa, most subjects are considered protected from MenA disease.
  
  
  BACKGROUND
  PsA-TT-003 (ISRCTN87739946); PsA-TT-003a (ISRCTN46335400).
authors.affiliation: Institut de Recherche pour le Développement, Niakhar, Sénégal.
authors.forename: Aldiouma
authors.initials: A
authors.lastname: Diallo
authors.affiliation: Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali.
authors.forename: Samba O
authors.initials: SO
authors.lastname: Sow
authors.affiliation: Medical Research Council Laboratories, Basse, The Gambia.
authors.forename: Olubukola T
authors.initials: OT
authors.lastname: Idoko
authors.affiliation: Shirdi Sai Baba Hospital, Vadu/King Edward Memorial Hospital and Research Centre, Pune, India.
authors.forename: Siddhivinayak
authors.initials: S
authors.lastname: Hirve
authors.affiliation: Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom.
authors.forename: Helen
authors.initials: H
authors.lastname: Findlow
authors.affiliation: Meningitis Vaccine Project, PATH, Ferney-Voltaire, France Meningitis Vaccine Project, Department of Immunization, Vaccines and Biologicals, World Health Organization, Geneva, Switzerland.
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Preziosi
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Elie
authors.affiliation: Serum Institute of India, Ltd, Pune.
authors.forename: Prasad S
authors.initials: PS
authors.lastname: Kulkarni
authors.affiliation: DiagnoSearch Life Sciences, Mumbai, India.
authors.forename: Varsha
authors.initials: V
authors.lastname: Parulekar
authors.affiliation: Institut de Recherche pour le Développement, Niakhar, Sénégal.
authors.forename: Bou
authors.initials: B
authors.lastname: Diarra
authors.affiliation: Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali.
authors.forename: Fadima
authors.initials: F
authors.lastname: Cheick Haidara
authors.affiliation: Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali.
authors.forename: Fatoumata
authors.initials: F
authors.lastname: Diallo
authors.affiliation: Department of Pediatrics, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore.
authors.forename: Milagritos
authors.initials: M
authors.lastname: Tapia
authors.affiliation: Medical Research Council Laboratories, Basse, The Gambia.
authors.forename: Adebayo K
authors.initials: AK
authors.lastname: Akinsola
authors.affiliation: GlaxoSmithKline Vaccines, Wavre, Belgium.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Adegbola
authors.affiliation: Shirdi Sai Baba Hospital, Vadu/King Edward Memorial Hospital and Research Centre, Pune, India.
authors.forename: Ashish
authors.initials: A
authors.lastname: Bavdekar
authors.affiliation: Shirdi Sai Baba Hospital, Vadu/King Edward Memorial Hospital and Research Centre, Pune, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Juvekar
authors.affiliation: Meningitis Vaccine Project, PATH, Ferney-Voltaire, France.
authors.forename: Julie
authors.initials: J
authors.lastname: Chaumont
authors.affiliation: Meningitis Vaccine Project, PATH, Ferney-Voltaire, France.
authors.forename: Lionel
authors.initials: L
authors.lastname: Martellet
authors.affiliation: Meningitis Vaccine Project, PATH, Ferney-Voltaire, France.
authors.forename: Elisa
authors.initials: E
authors.lastname: Marchetti
authors.affiliation: Serum Institute of India, Ltd, Pune.
authors.forename: Marc F
authors.initials: MF
authors.lastname: LaForce
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Plikaytis
authors.affiliation: Meningitis Vaccine Project, PATH, Ferney-Voltaire, France.
authors.forename: Godwin C
authors.initials: GC
authors.lastname: Enwere
authors.affiliation: Meningitis Vaccine Project, PATH, Seattle, Washington.
authors.forename: Yuxiao
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom.
authors.forename: Ray
authors.initials: R
authors.lastname: Borrow
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: George
authors.initials: G
authors.lastname: Carlone
authors.affiliation: Meningitis Vaccine Project, PATH, Ferney-Voltaire, France.
authors.forename: Simonetta
authors.initials: S
authors.lastname: Viviani
mesh_terms: D000293:Adolescent; D000328:Adult; D000349:Africa; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D001770:Blood Bactericidal Activity; D002648:Child; D002675:Child, Preschool; D003165:Complement System Proteins; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D064368:Healthy Volunteers; D006801:Humans; D007194:India; D008297:Male; D022401:Meningococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D011817:Rabbits; D013997:Time Factors; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; C573970:MenAfriVac; D022401:Meningococcal Vaccines; C000610192:PsACWY vaccine; D003165:Complement System Proteins
keywords: African meningitis belt; India; MenA conjugate vaccine; antibody persistence