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Opsonophagocytic Killing Assay to Assess Immunological Responses Against Bacterial Pathogens
Published on: April 5, 2019
Essential criteria for evaluation of pneumococcal conjugate vaccine candidates
1Wyeth Vaccines, Wyeth Pharmaceuticals, 500 Arcola Road, Collegeville, PA 19426, USA. paradipr@wyeth.com
Abstract:
In 2003, the World Health Organization recommended a concentration of enzyme-linked immunosorbent assay (ELISA) immunoglobulin G (IgG) anti-capsular antibody of 0.35 microg/mL as a reference value that correlates to protection against invasive pneumococcal disease. This threshold can be used to demonstrate immunologic non-inferiority of a new vaccine in comparison trials that use pneumococcal conjugate vaccines (PCVs) as a comparator. An investigational 13-valent PCV (PCV13) compared with seven-valent PCV (PCV7) demonstrated that all of the pneumococcal serotypes contained in PCV13 were immunogenic, with 88-98% of vaccinees achieving antibody concentration > or = 0.35 microg/mL for serotypes shared with PCV7 and >96% for six additional serotypes.
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