Tolerability and immunogenicity of an 11-valent pneumococcal conjugate vaccine in adults

We studied the safety and immunogenicity in healthy adults of an 11-valent pneumococcal conjugate vaccine. Capsular polysaccharides (PS) of serotypes 1, 4, 5, 7F, 9V, 19F and 23F were conjugated to tetanus toroid, and of sero types 3, 6B, 14 and 18C to diphtheria toroid. Ten subjects received the con jugate vaccine with and the other ten subjects without aluminium hydroxide adjuvant. The reference vaccine was a marketed 23-valent PS vaccine. Safety data were recorded over 5 days after the immunisation. IgG antibody concen trations, avidity and subclass distribution were measured by EIA. The conju gate without aluminium induced more local adverse effects than the conjugat e with aluminium or PS vaccine. All vaccines evoked significant antibody in creases to all vaccine specific antigens. Both conjugate vaccines induced a ntibodies mainly of IgG(2) subclass, and adjuvanted conjugate vaccine induc ed IgG antibodies with increased avidity. This first administration, to man , of a mixed protein carrier 11-valent pneumococcal conjugate vaccine demon strated its ability to induce an immune response without significant advers e effects, enabling further study on its use in paediatric populations. (C) 2001 Elsevier Science Ltd. All rights reserved.