Development of a new 15-valent pneumococcal conjugate vaccine (PCV15) and evaluation of its immunogenicity. (September 2019)

• Record Type: Journal Article
• Authors: Lee, Chankyu; Choi, Seuk Keun; Kim, Rock Ki; Kim, Heeyoun; Whang, Yoon Hee; Pharm, Huyen; Cheon, Hyunwoo; Yoon, Do-Young; Kim, Chan Wha; Baik, Yeong Ok; Park, Sung Soo; Lee, Inhwan
• Is Part Of: Biologicals. Volume 61(2019)
• Page Start: 32
• Page End: 37
• Publication Date: 2019-09
• Subjects: Polyvalent pneumococcal conjugate vaccine -- Immunogenicity -- Enzyme-linked immunosorbent assay -- Opsonophagocytic activity; Biological products -- Standards -- Periodicals; Biological Products -- Periodicals; Biological Products -- standards -- Periodicals; Produits biologiques -- Normes -- Périodiques; Biological products -- Standards; Periodicals; 615.37
• DOI: 10.1016/j.biologicals.2019.07.005
• Languages: English
• ISSNs: 1045-1056

Abstract

Abstract: A new 15-valent pneumococcal conjugate vaccine (PCV15) against serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 11A, 14, 18C, 19A, 19F, 22F, and 23F has been developed using aluminum phosphate as an adjuvant. Using the rabbit model, immunogenicity of each serotype was evaluated by measuring antigen specific antibodies and functional antibody titers and comparing them to a control vaccine, Prevnar13®. Among the shared serotypes in both PCV15 and Prevnar13®, Type 3 and 23F in PCV15 exhibited a lower opsonic index than Prevnar13®. Conversely, the other types showed greater or nearly the same immunogenic effects. Type 11A and 22F are two additional serotypes included in PCV15, and only 22F showed a reasonable opsonic index compared with other types. Type 11A exhibited a basal level fold-increase in OPA; thus, we further optimized 11A as well as 3 and 23F by controlling the polysaccharide-to-protein conjugation ratio as a variable. Antibody levels and functional antibody activities were evaluated by ELISA and OPA, and improved levels of immunogenic activities were observed for all three serotypes. In this study, we propose a new PCV15 candidate, in which the common 13 serotypes and a licensed control vaccine have equivalent efficacy while two additional serotypes showed adequate immunogenicity in the rabbit model.