Pneumococcal polysaccharides and their use in immunogenic polysaccharide-carrier protein conjugates

Abstract

The present invention provides capsular polysaccharides from Streptococcus pneumoniae serotypes identified using NMR. The present invention further provides polysaccharide-protein conjugates in which capsular polysaccharides from one or more of these serotypes are conjugated to a carrier protein such as CRM197. Polysaccharide-protein conjugates from one or more of these serotypes may be included in multivalent pneumococcal conjugate vaccines having polysaccharides from multiple additional Streptococcus pneumoniae serotypes.

1 - 30 . (canceled) 
     
     
         31 . A method of inducing an immune response to a  Streptococcus pneumoniae  capsular polysaccharide, comprising administering to a human an immunologically effective amount of an immunogenic composition comprising-a polysaccharide-carrier protein conjugate and a pharmaceutically acceptable carrier, wherein the polysaccharide of the polysaccharide-carrier protein conjugate comprises an  S. pneumoniae  serotype 23A polysaccharide repeating unit of the following structure: 
       
         
           
           
               
               
           
         
         wherein the carrier protein is CRM197; and further wherein the polysaccharide-carrier protein conjugate has a molecular weight from 1,000 kDa to 10,000 kDa; and further wherein the polysaccharide-carrier protein conjugate has a polysaccharide to carrier protein mass ratio from 0.5 to 3.0. 
       
     
     
         32 - 34 . (canceled) 
     
     
         35 . The method of  claim 31 , wherein the immunogenic composition further comprises one or more additional polysaccharide-carrier protein conjugates, wherein each of the conjugates comprises a polysaccharide of a particular  S. pneumoniae  serotype conjugated to CRM197, and wherein the  S. pneumoniae  serotypes are selected from the group consisting of: 1, 2, 3, 4, 5, 6A, 6B, 6C, 6D, 7B, 7C, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15A, 15B, 15C, 17F, 18C, 19A, 19F, 20, 21, 22A, 22F, 23B, 23F, 24F, 27, 28A, 31, 33F, 34, 35A, 35B, 35F, and 38. 
     
     
         36 . The method of  claim 35 , wherein the one or more additional polysaccharide-carrier protein conjugates comprises a polysaccharide of  S. pneumoniae  23B. 
     
     
         37 . The method of  claim 35 , wherein the immunogenic composition is formulated to comprise: 0.4 to 4 μg/mL of each polysaccharide present, except for serotype 6B polysaccharide which, if present, comprises 0.8 to 8 μg/mL of polysaccharide; and CRM197 carrier protein in an amount from about 0.5× to 3× the total amount of polysaccharide. 
     
     
         38 . The method of  claim 37 , wherein the immunogenic composition is formulated to further comprise 150 mM sodium chloride, 20 mM L-histidine buffer, and 0.05 to 2% w/v surfactant. 
     
     
         39 . The method of  claim 38 , wherein the immunogenic composition further comprises an adjuvant. 
     
     
         40 . The method of  claim 39 , wherein the adjuvant is an aluminum-based adjuvant. 
     
     
         41 . The method of  claim 40 , wherein the adjuvant is selected from the group consisting of aluminum phosphate, aluminum sulfate, and aluminum hydroxide. 
     
     
         42 . The method of  claim 41 , wherein the adjuvant is aluminum phosphate. 
     
     
         43 . The method of  claim 31 , wherein the 23A polysaccharide repeating unit is conjugated at the 2 nd  or 3 rd  carbon position of α-Rhap or β-Glcp. 
     
     
         44 . The method of  claim 31 , wherein the degree of conjugation of the conjugate is between 2 and 15. 
     
     
         45 . The method of  claim 31 , wherein the degree of conjugation of the conjugate is between 8 and 12. 
     
     
         46 . The method of  claim 31 , wherein the polysaccharide has a molecular weight of between 50 kDa and 1,000 kDa. 
     
     
         47 . The method of  claim 31 , wherein the polysaccharide has a molecular weight of between 100 kDa and 300 kDa. 
     
     
         48 . The method of  claim 31 , wherein the polysaccharide-carrier protein conjugate has a polysaccharide to carrier protein mass ratio from 0.5 to 1.5. 
     
     
         49 . The method of  claim 31 , wherein the polysaccharide-carrier protein conjugate has a polysaccharide to carrier protein mass ratio from 0.8 to 1.2. 
     
     
         50 . The method of  claim 31 , wherein the immunogenic composition comprises less than about 25% of non-covalently associated polysaccharide compared to the total amount of polysaccharide. 
     
     
         51 . The method of  claim 31 , wherein the immunogenic composition comprises less than about 15% of non-covalently associated polysaccharide compared to the total amount of polysaccharide. 
     
     
         52 . The method of  claim 31 , wherein the 23A polysaccharide repeating units are conjugated at the 2 nd  or 3 rd  carbon position of α-Rhap or β-Glcp; wherein the polysaccharide has a molecular weight of between 100 kDa and 300 kDa; wherein the degree of conjugation of the conjugate is between is between 8 and 12; wherein the mass ratio of polysaccharide to carrier protein in the conjugate is between 0.8 and 1.2; and wherein the conjugate comprises less than about 15% of non-covalently associated polysaccharide compared to the total amount of polysaccharide. 
     
     
         53 . The method of  claim 35 , wherein the immunogenic composition is a single 0.5 mL dose formulated to comprise: 2 μg of each polysaccharide present, except for serotype 6B polysaccharide which, if present, is 4 μg; about 32 μg CRM197 carrier protein; 0.125 mg aluminum phosphate adjuvant; 150 mM sodium chloride, 20 mM L-histidine buffer, and 0.2% w/v PS-20.