title: Safety and immunogenicity of three doses of a five-valent pneumococcal conjugate vaccine in children younger than two years with and without human immunodeficiency virus infection.
abstract: OBJECTIVE
  To assess the safety and immunogenicity of three doses of a five-valent (types 6B, 23F, 14, 18C, and 19F) pneumococcal conjugate vaccine (PCV) among children younger than 2 years who are and are not infected with human immunodeficiency virus (HIV).
  
  
  METHODS
  A convenience sample of 18 HIV-infected children 2 years and younger (mean, 12.9 months) received three doses (each separated by 2 months) of PCV. An additional convenience sample of 33 non-HIV-infected children of virtually identical age, race, and sex as the HIV-infected group were randomized in a double-blind fashion to receive three doses of PCV or saline placebo. Safety data were collected for 72 hours after each vaccination. Sera were obtained before each and 1 month after the third vaccination to determine vaccine type-specific immunoglobulin G pneumococcal antibody titers by an enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Seventeen HIV- and 30 non-HIV-infected children completed the study. The PCV was well tolerated by both HIV- and non-HIV-infected children. No significant differences in local or systemic reactions were noted between HIV- and non-HIV-infected PCV or placebo recipients. Three doses of PCV were immunogenic, as evidenced by 16- to 659-fold increases in type-specific geometric mean antibody titers over prevaccination levels in HIV- and non-HIV-infected children. With respect to an arbitrary protective level, 78% of the antibody titers from HIV-infected children and 88% of the titers from non-HIV-infected children were 1.0 microgram/mL or greater 1 month after the third PCV dose. HIV-infected children with milder disease (Centers for Disease Control and Prevention classes N1-2, A1-2, and B1) were more likely to have protective antibody titers after the first and second PCV doses than HIV-infected children with more advanced disease (Centers for Disease Control and Prevention classes N3, A3, B2-3, and C1-3). However, after the third PCV dose, these differences disappeared.
  
  
  CONCLUSIONS
  Three doses of PCV seem safe and immunogenic in both HIV- and non-HIV-infected children younger than 2 years. This type of vaccine should result in a marked reduction in systemic pneumococcal disease in both HIV- and non-HIV-infected children. Given the high incidence of invasive pneumococcal disease in HIV-infected children, this vaccine may markedly improve the quality of life for this unfortunate group of children.
authors.affiliation: Department of Pediatrics, University of Maryland at Baltimore, School of Medicine 21201, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: King
authors.forename: P E
authors.initials: PE
authors.lastname: Vink
authors.forename: J J
authors.initials: JJ
authors.lastname: Farley
authors.forename: M
authors.initials: M
authors.lastname: Smilie
authors.forename: M
authors.initials: M
authors.lastname: Parks
authors.forename: R
authors.initials: R
authors.lastname: Lichenstein
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000276:immunology*; D001428:Bacterial Vaccines / Q000009:adverse effects / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D007223:Infant; D011008:Pneumococcal Infections / Q000276:immunology*; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate / Q000009:adverse effects / Q000276:immunology
chemical_list: D001428:Bacterial Vaccines; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate; C105256:five-valent pneumococcal conjugate vaccine