The invention relates to the use of fraction A of Quil A together with atleast one other adjuvant for the preparation of an adjuvant composition, wherethe included adjuvant components act synergistically to enhance level ofimmune response and (with) and have synergistic immunomodulating activity onthe co-administered antigens or immunogens. The at least one other adjuvantmay be chosen from saponins, naturally occurring, synthethic or semisyntheticsaponin molecules； e.g. saponins and saponin fractions from Quil A, cell wallskeleton, blockpolymers, TDM, lipopeptides, LPS and LPS-derivatives, Lipid Afrom different bacterial species and derivatived thereof, e.g., monophosphoryllipid A. CpG variants. CT and LT or fractions (derivates) thereof.
