Prospective Randomized Controlled Phase 4 Study on the Safety and Immunogenicity of Sequential Pneumococcal Immunization in Preschool Asthmatics
Prospective Randomized Controlled Phase 4 Study on the Safety and Immunogenicity of Sequential Pneumococcal Immunization in Preschool Asthmatics
Asthma is a major health problem in preschool children. Infections by pneumococci a the most frequent cause of airway infections, which tend to cause worsening of asthma. Vaccination against pneumococci is recommended by scientific boards and the medical community, in order to reduce the burden of disease. Data on the immunogenicity and safety of pneumococcal immunization in preschool asthmatics are scarce.
Respiratory infections are major triggers of exacerbations in preschool asthma. Many countries' guidelines recommend immunization against pneumococci for patients suffering from chronic airway disease. Also the interval between priming and booster is a matter of debate.
We immunize a large group of preschool asthmatics (2-5 years old) sequentially: one dose of seven-valent pneumococcal conjugate vaccine (PCV-7) followed by a single dose of 23-valent pneumococcal polysaccharide vaccine (PPV-23). We randomly assign half of the vaccinees to receive PPV-23 eight weeks after PCV-7 (group A), and the rest to a 10-month interval (group B). Pneumococcal antibody concentrations to serotype 4, 5, 6B, 7, 9V, 14, 18c, 19F, and 23F are determined initially, after two, and 12 months after PCV-7. Local and systemic reactions to each vaccine are recorded.
Inclusion Criteria:
Exclusion Criteria: