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Effects of Prior Polysaccharide Vaccination on Magnitude, Duration, and Quality of Immune Responses to and Safety Profile of a Meningococcal Serogroup C Tetanus Toxoid Conjugate Vaccination in Adults

2004; American Society for Microbiology; Volume: 11; Issue: 6 Linguagem: Inglês

10.1128/cdli.11.6.1100-1104.2004

1556-6811

Jo Southern, Sarah Deane, Lindsey Ashton, Ray Borrow, David Goldblatt, Nick Andrews, Paul Balmer, Rhonwen Morris, J. Simon Kroll, Elizabeth Miller,

Inhalation and Respiratory Drug Delivery

ABSTRACT Extensive use of meningococcal AC polysaccharide (MACP) vaccines has raised concerns about induction of immunologic hyporesponsiveness to C polysaccharide. We investigated the immunogenicity and safety of a meningococcal C-tetanus conjugate (MCC-TT) vaccine in naïve adults and prior MACP vaccinees. Laboratory staff ( n = 113) were recruited; 73 were naïve to meningococcal vaccination, and 40 had previously received ≥1 dose of MACP vaccine. Blood was taken prior to MCC-TT vaccination and 1 week, 1 month, and 6 months later. At each time point, proportions of subjects with serum bactericidal antibody (SBA) titers of ≥8 or ≥128 were similar ( P > 0.46); >94% of subjects achieved titers of ≥128 at 1 month. However, the geometric mean titer (GMT) of SBA at 1 month was higher in the naïve (1,757; 95% confidence interval [95% CI], 1,102 to 2,803) than in the previously vaccinated (662; 95% CI, 363 to 1,207) group ( P = 0.02), and similarly at 6 months ( P < 0.001). Conversely, geometric mean concentrations (GMCs) of serogroup C-specific immunoglobulin G (IgG) were significantly higher in the previously vaccinated group pre-MCC-TT and at 1 week; the groups were similar at 1 month, and there was some evidence that the GMC for the previously vaccinated group was higher at 6 months. Qualitative differences in antibodies between groups were demonstrated by using the SBA/IgG ratio, though avidity measures were similar for the two groups throughout the study. MCC-TT was well tolerated, with similar safety profiles in the two groups. Pain in the arm and headache were the most frequently reported events following vaccination. The study shows that MCC-TT is safe and immunogenic in naïve and previously MACP-vaccinated adults, though the magnitude and persistence of postvaccination SBA responses in the latter group were lower.