title: The Antibody Response Following a Booster With Either a 10- or 13-valent Pneumococcal Conjugate Vaccine in Toddlers Primed With a 13-valent Pneumococcal Conjugate Vaccine in Early Infancy.
abstract: Both the 13- and 10-valent pneumococcal conjugate vaccines (PCV-13; PCV-10) are immunogenic and effective against vaccine-type pneumococcal disease when given to young children. However, limited data are available regarding the interchangeability of these 2 vaccines.
  
  
  
  UK children (n = 178) who had previously been vaccinated with PCV-13 at 2 and 4 months were randomized to receive either a PCV-13 or a PCV-10 booster at 12 months of age. PCV-13 vaccine-type antipolysaccharide serum immunoglobulin G (IgG) concentrations and opsonophagocytic assay titers were measured before and at 1 and 12 months following vaccination. The primary objective was to assess noninferiority of PCV-10 compared with PCV-13.
  
  
  
  For 8 of the PCV-10 serotypes at least 97% of participants in both groups had IgG concentrations ≥0.35 µg/mL at 1 month after vaccination; inferior responses were seen for serotypes 5 and 9V following the PCV-10 compared with the PCV-13 booster. Post booster geometric mean IgG concentrations and opsonophagocytic assay titers were significantly superior for most serotypes in PCV-13 compared with PCV-10 recipients, whereas similar or inferior responses were seen for serotypes 4, 18C, and 19F. Although some increase in antibody was seen in PCV-10 recipients against the serotypes 6A and 19A (serotypes that cross-react with 6B and 19F in PCV-10, respectively) at 1-month post booster, these responses were significantly lower than in the PCV-13 group.
  
  
  
  In PCV-13 primed infants, a PCV-10 booster is generally less immunogenic than a PCV-13 booster. For the 3 serotypes in PCV-10 with higher antigen content and/or conjugation to diphtheria or tetanus toxoid carrier proteins, higher or similar booster responses were seen in PCV-10 recipients. Although these findings suggest that responses are generally better with a PCV-13 booster among PCV-13 primed children, the clinical significance of these differences in immunogenicity is unclear.
authors.affiliation: From the *Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom; †Paediatric Immunology, University Children's Hospital Zürich, Zürich, Switzerland; ‡Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, United Kingdom; and §Institute of Child Health, University College London, London, United Kingdom.
authors.forename: Johannes
authors.initials: J
authors.lastname: Trück
authors.forename: Sena
authors.initials: S
authors.lastname: Jawad
authors.forename: David
authors.initials: D
authors.lastname: Goldblatt
authors.forename: Lucy
authors.initials: L
authors.lastname: Roalfe
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Snape
authors.forename: Merryn
authors.initials: M
authors.lastname: Voysey
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Pollard
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D000917:Antibody Formation / Q000187:drug effects / Q000276:immunology; D004165:Diphtheria / Q000276:immunology / Q000517:prevention & control; D005260:Female; D006801:Humans; D007117:Immunization, Secondary / Q000379:methods; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D008297:Male; D011008:Pneumococcal Infections / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D006113:United Kingdom; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology
chemical_list: C586648:10-valent pneumococcal conjugate vaccine; C538862:13-valent pneumococcal vaccine; D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate