The invention provides immunogenic compositions comprising (a) a capsular saccharide antigen from serogroup C of N. meningitidis, and (b) a chitosan adjuvant. The composition preferably comprises (c) one or more further antigens and/or (d) one or more further adjuvants. The compositions are particularly suitable for mucosal delivery, including intranasal delivery. The invention also provides immunogenic compositions for mucosal delivery comprising capsular saccharides from at least two of serogroups A, C, W135 and Y of N. meningitidis. It is preferred that the capsular saccharides in the compositions of the invention are conjugated to carrier protein(s) and/or are oligosaccharides. Conjugated oligosaccharide antigens are particularly preferred.
