Provided is an immunogenic composition comprising 13 different polysaccharide-protein conjugates. Each of the conjugates comprises a capsular polysaccharide prepared from a different serotype Streptococcus pneumoniae conjugated to a carrier protein, that is, 12 serotypes selected from the group consisting of 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F and serotype 2 or 9N. The immunogenic composition formulated into a vaccine comprising an aluminum-based adjuvant increases coverage with respect to pneumococcal diseases in infants and children.
