A lyophilised formulation for vaccines against Neisseria meningitidis comprises (i) an immunogen for raising an immune response against N.meningitidis serogroup B, and (ii) a conjugated capsular saccharide from one or more of N.meningitidis serogroups A, C, W135 and/or Y. The lyophilised antigens can be reconstituted into liquid form at the time of use ready for administration to a patient, and reconstitution can use an adjuvant comprising an oil-in-water emulsion. The formulation gives excellent result in terms of both stability and immunogenicity.