An immunogenic compositions comprising influenza virus antigen derived from at least 5 influenza virus strains and one or more compounds of formula (I) or a physiologically acceptable salt or ester thereof； Wherein R1 represents H or C1-6 alkyl； R2 and R3 independently represent C1-6 alkyl. The composition preferably comprises influenza virus antigens derived from 8-18 influenza virus strains, in particular 15 strains； and preferably from at least two different virus types, in particular types A and B. The compositions preferably comprises at least one influenza virus antigen derived from a H1N1 subtype of type A and at least one derived from a H3N2 subtype of type A. The compound of formula (I) is preferably either dimethylglycine or trimethylglycine or both. The composition is preferably prepared via freezing, heat-treating and/or freeze drying a single aqueous composition comprising the influenza virus antigens and the compound of formula (I)； or at least two aqueous compositions comprising at least one influenza virus antigen and a compound of formula (I) and combining the resulting compositions. Uses of and methods of treatment comprising the compositions are also disclosed for inducing an immune response against influenza virus.
