1 Departments of International Health and Pediatrics, School of Medicine, Johns Hopkins University, Baltimore, MD
2 Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD
3 Departments of Preventive Medicine, Medicine (Infectious Diseases), Vanderbilt University School of Medicine, Nashville, TN
4 Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN
5 Departments of Microbiology and Immunology and Pediatrics, Baylor College of Medicine, Houston, TX
6 Department of Pediatrics, University of Rochester School of Medicine, Rochester, NY
7 Department of Pediatrics and the Center for Vaccine Development, University of Maryland School of Medicine, Baltimore
8 Department of Medicine, St Louis University School of Medicine, Rockville, MD
9 Division of Bacterial Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Rockville, MD
Objective. To compare prospectively the reactogenicity and immunogenicity of two licensed whole-cell pertussis vaccines.
Methods. We conducted a prospective, randomized, double-blinded assessment of two licensed whole-cell pertussis vaccines with diphtheria and tetanus toxoids that were included in a multicenter trial evaluating 13 acellular pertussis vaccines. Infants were immunized at 2, 4, and 6 months of age with a single lot of Lederle (309 infants) or Massachusetts Public Health Biologic Laboratories (MPHBL; 94 infants) vaccine.
Results. The group receiving the Lederle vaccine demonstrated significantly higher antibody titers to pertussis toxin by enzyme-linked immunosorbent assay (ELISA) and by the Chinese hamster ovary cell pertussis toxin neutralization assay, and to fimbrial antigens by ELISA, as well as higher mean agglutinin titers. In contrast, the group receiving the MPHBL vaccine demonstrated higher ELISA antibody levels to filamentous hemagglutinin and pertactin. Similar differences were observed in the proportions of vaccinees seroconverting to these antigens. Rates of systemic and local reactions were relatively low for both vaccines. Although the Lederle product had substantially lower reactogenicity in this study than previously reported for that vaccine, the MPHBL vaccine was significantly less reactogenic in nearly all clinical categories.
Conclusion. The two whole-cell vaccines demonstrated statistically significant differences in postimmunization antibody levels to all six evaluated pertussis antigens. Whether these statistically significant differences in antibody levels have clinical relevance is not clear. Rates of nearly all local and systemic reactions were significantly lower among the MPHBL group than the Lederle group. Licensed whole-cell diphtheria-tetanus-pertussis vaccines produced by different manufacturers cannot be assumed to be similar in reactogenicity or immunogenecity.