661. Long-Term Immune Responses to Pneumococcal Conjugate Vaccines in Children Previously Vaccinated with 7-valent Pneumococcal Conjugate Vaccine
Session: Poster Abstract Session: Pneumococcal Vaccines
Friday, October 21, 2011
Room: Poster Hall B1
Handouts
  • 661_NicolaKlein.pdf (2.1 MB)
  • Background: 7-valent pneumococcal conjugate vaccine (PCV7) has reduced the incidence of pneumococcal diseases caused by vaccine serotypes. We evaluated late immune responses following vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) >10 years after vaccination with PCV7 in infancy compared with a PCV7-naïve cohort.

    Methods: In this single-center, open-label study we provided a single dose of PCV13 to children aged 11–14 years who had received either PCV7 (PCV7/PCV13 arm) or meningococcal C conjugate vaccine (MnCC/PCV13 arm) during infancy. Endpoints included the proportions of subjects 1 month after vaccination achieving serotype-specific IgG concentrations ≥0.35 µg/mL by standard ELISA and the proportions of subjects achieving opsonophagocytic activity (OPA) assay titers ≥ the lower limit of quantitation (LLQ). We recorded local reactions and systemic events for 4 days postvaccination and adverse events (AEs) for 6 months.

    Results: 74 subjects were vaccinated with PCV13 (PCV7/PCV13, n = 38; MnCC/PCV13, n = 36). Prevaccination with PCV13, both arms had similar proportions of subjects with IgG ≥0.35 µg/mL (>62.9% for all PCV13 serotypes except serotype 4 [≥28%]). Proportions of subjects with OPA ≥LLQ ranged from 21.4% (23F) to 90.6% (6B) for the PCV7 serotypes and from 2.8% (5) to 72.7% (19A) for the 6 additional serotypes. One month postvaccination, all subjects in both arms achieved IgG ≥0.35 µg/mL for all vaccine serotypes except serotype 14 (MnCC/PCV13, 97.1%) and PCV13-specific serotype 3 (PCV7/PCV13, 94.7%; MnCC/PCV13, 97.0%); and OPA ≥LLQ for all serotypes except 19F (PCV7/PCV13, 97.4%), 1 (MnCC/PCV13, 97.1%), 5 (PCV7/PCV13, 89.5%; MnCC/PCV13, 88.6%), and 19A (PCV7/PCV13, 97.4%). Local reactions and fever were mild or moderate; no serious AEs were reported.

    Conclusion: A single dose of PCV13 was immunogenic in children aged 11–14 years regardless of previous vaccination with PCV7 or MnCC vaccine. PCV13 was safe and well tolerated.


    Subject Category: I. Adult and Pediatric Vaccines

    Nicola Klein, MD, PhD1, Kathleen Ensor, BA, RN1, Sylvie Jouve, PhD2, Michele Moscariello3 and Paul McGovern3, (1)Kaiser Permanente Vaccine Study Center, Oakland, CA, (2)Pfizer Inc, Paris La Defense, France, (3)Pfizer Inc, Collegeville, PA

    Disclosures:

    N. Klein, Sanofi Pasteur: Grant Investigator, Research grant
    Merck & Co.: Grant Investigator, Research grant
    GSK: Grant Investigator, Research grant
    Novartis: Grant Investigator, Research grant
    MedImmune: Grant Investigator, Research grant
    Pfizer: Grant Investigator, Research grant

    K. Ensor, Sanofi Pasteur: Grant Investigator, Research grant
    Merck & Co.: Grant Investigator, Research grant
    GSK: Grant Investigator, Research grant
    Novartis: Grant Investigator, Research grant
    MedImmune: Grant Investigator, Research grant
    Pfizer Inc: Grant Investigator, Research grant

    S. Jouve, Pfizer Inc: Employee, Salary

    M. Moscariello, Pfizer Inc: Employee, Salary

    P. McGovern, Pfizer Inc.: Employee, Salary

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.