Polysaccharide-protein conjugate vaccines

摘要

Methods for synthesis and manufacture of polysaccharide-protein conjugate vaccines at high yield are provided. The methods involve reaction of a hydrazide group on one reactant with an aldehyde or cyanate ester group on the other reactant. The reaction proceeds rapidly with a high conjugation efficiency, such that a simplified purification process can be employed to separate the conjugate product from the unconjugated protein and polysaccharide and other small molecule by-products.

主权项

1. A method for preparing a conjugate vaccine, the method comprising:
reacting a polysaccharide with an oxidizing agent, whereby a solution of an aldehyde-activated polysaccharide is obtained; buffer exchanging the solution of the aldehyde-activated polysaccharide to a pH of from 7 to 8; reacting a protein with carbohydrazide or a dihydrazide in the presence of 1-[3-(dimethylamino)propyl]-3-ethyl carbodiimide hydrochloride at a pH of from 6 to 7, whereby a solution of an hydrazide-activated protein is obtained; raising a pH of the solution of the hydrazide-activated protein to from 7.0 to 11; buffer exchanging the solution of the hydrazide-activated protein to a pH of from 10.0 to 11.0; reacting the aldehyde-activated polysaccharide with the hydrazide-activated protein at a pH of from 6 to 8, whereby a conjugate comprising one or more C═N double bonds is obtained; and reducing the C═N double bonds of the conjugate to C—N single bonds, whereby a conjugate vaccine capable of stimulating an immune response is obtained.