Analysis of saccharide vaccines without interference

Abstract

The invention is based on methods that allow analysis of mixed meningococcal saccharides from multiple serogroups even though they share monosaccharide units. With a combination of saccharides from serogroups C, W135 and Y, the invention analyses sialic acid, glucose and galactose content. The glucose and galactose results are used to directly quantify saccharides from serogroups Y and W135, respectively, and the combined glucose and galactose content is subtracted from the sialic acid content to quantify saccharides from serogroup C. The three serogroups can thus be resolved even though their monosaccharide contents overlap. The three different monosaccharide analyses can be performed on the same material, without interference between the monosaccharides and without interference from any other saccharide materials in the composition (e.g. lyophilisation stabilisers). The method can be used to analyse total and free saccharide in conjugate vaccines and simplifies quality control of vaccines containing capsular saccharides from multiple serogroups.

1 . Two batches of a vaccine, wherein:
 (a) each of the batches of vaccine comprises: a conjugate of a capsular saccharide from serogroup C of  Neisseria meningitidis  and one or both of: (i) a conjugate of a capsular saccharide from serogroup W135 of  Neisseria meningitidis ; and/or (ii) a conjugate of a capsular saccharide from serogroup Y of  Neisseria meningitidis;      (b) the concentration of conjugated serogroup C saccharide in the first batch is C 1 ;   (c) the concentration of conjugated serogroup C saccharide in the second batch is C 2 ;   if applicable, (d) the concentration of conjugated serogroup W135 saccharide in the first batch is W 1 ;   if applicable, (e) the concentration of conjugated serogroup W135 saccharide in the second batch is W 2 ;   if applicable, (f) the concentration of conjugated serogroup Y saccharide in the first batch is Y 1 ;   if applicable, (g) the concentration of conjugated serogroup Y saccharide in the second batch is Y 2 ;   and wherein (h) the ratios C 1 /C 2 , W 1 /W 2  and Y 1 /Y 2  are each between 0.90 and 1.10.   
     
     
         2 . The batches of  claim 1 , wherein: (i) the concentration of unconjugated serogroup C saccharide in the first batch is C 3 ; (j) the concentration of unconjugated serogroup C saccharide in the second batch is C 4 ; if applicable, (k) the concentration of unconjugated serogroup W135 saccharide in the first batch is W 3 ; if applicable, (l) the concentration of unconjugated serogroup W135 saccharide in the second batch is W 4 ; if applicable, (m) the concentration of unconjugated serogroup Y saccharide in the first batch is Y 3 ; if applicable, (n) the concentration of unconjugated serogroup Y saccharide in the second batch is Y 4 ; (o) the ratios C 3 /C 4 , W 3 /W 4  and Y 3 /Y 4  are each between 0.90 and 1.10, and preferably are each between 0.95 and 1.05. 
     
     
         3 . The batches of  claim 2 , wherein (p) the ratios C 3 /C 1 , C 4 /C 2 , W 3 /W 1 , W 4 /W 2 , Y 3 /Y 1  and Y 4 /Y 2  are each less than 0.20. 
     
     
         4 . The batches of  claim 1 , wherein each of the batches of vaccine comprises a conjugate of a capsular saccharide from serogroup C of  Neisseria meningitidis  and a conjugate of a capsular saccharide from serogroup W135 of  Neisseria meningitidis.    
     
     
         5 . The batches of  claim 1 , wherein each of the batches of vaccine comprises a conjugate of a capsular saccharide from serogroup C of  Neisseria meningitidis  and a conjugate of a capsular saccharide from serogroup Y of  Neisseria meningitidis.    
     
     
         6 . The batches of  claim 1 , wherein each of the batches of vaccine comprises a conjugate of a capsular saccharide from serogroup C of  Neisseria meningitidis  and both of: (i) a conjugate of a capsular saccharide from serogroup W135 of  Neisseria meningitidis ; and (ii) a conjugate of a capsular saccharide from serogroup Y of  Neisseria meningitidis.    
     
     
         7 . The batches of  claim 1 , wherein the ratios specified in (h) are based on a single sample from each batch being compared. 
     
     
         8 . The batches of  claim 1 , wherein the ratios specified in (h) are based on means from multiple samples of each batch. 
     
     
         9 . The batches of  claim 1 , wherein the two different batches are made by separate mixings of the same bulk single conjugates. 
     
     
         10 . The batches of  claim 1 , wherein the two different batches are made by mixing bulk single conjugates that were separately prepared. 
     
     
         11 . The batches of  claim 1 , wherein the saccharides are oligosaccharides. 
     
     
         12 . The batches of  claim 1 , wherein the saccharides are polysaccharides. 
     
     
         13 . The batches of  claim 1 , wherein the carrier proteins in the conjugates are diphtheria toxoid, tetanus toxoid or CRM 197 . 
     
     
         14 . The batches of  claim 1 , wherein the conjugates have a saccharide:protein ratio (w/w) of between 1:5 and 5:1. 
     
     
         15 . The batches of  claim 1 , wherein a sugar alcohol is included in the vaccine as a lyophilisation stabiliser. 
     
     
         16 . A process for quantifying saccharides from individual serogroups within a mixture of capsular saccharides from at least two different meningococcal serogroups, wherein:
 (a) the different serogroups comprise serogroup C of  Neisseria meningitidis  and one or both of:
 (i) serogroup W135 of  Neisseria meningitidis ; and/or (ii) serogroup Y of  Neisseria meningitidis;    
   (b) the process comprises a step of depolymerizing the capsular saccharides within the mixture. to give a depolymerized mixture; and   (c) the different serogroups are quantified by comparing the monosaccharide composition of the depolymerized mixture.