Multivalent pneumococcal glycoconjugate vaccines containing emerging serotype 24F

A method of manufacture of an immunogenic composition containing at least 25 capsular polysaccharides of Streptococcus pneumonia comprising Streptococcus pneumonia capsular polysaccharides of serotypes 1, 2, 3, 4, 5, 6B, 6C, 7F, 8, 9N, 9V, 10A, 12F, 14, 15A, 15B, 16F, 18C, 19A, 19F, 22F, 23F, 24F, 33F and 35B,

• activating the at least 25 capsular polysaccharides;
• conjugating the activated capsular polysaccharides directly or indirectly through linkers to carrier proteins;
• isolating individual conjugates by diafiltration;
• sterilizing individual conjugates;
• and
• collecting the sterilized individual conjugates as the immunogenic composition,
• wherein the 24F serotype capsular polysaccharide comprises a repeating unit of the chemical structure:
• and wherein the at least 25 capsular polysaccharides are conjugated to one or more carrier proteins, and at least one conjugation is through a bi-functional or a multifunctional spacer/linker.