The present invention relates to formulation comprising (i) at least one virus- based material, (ii) at least one polymer selected in the group of polyvinylpyrrolidone and derivatives thereof, (iii) at least one sugar , (iv) at least two different amino acids, (v) at least two pharmaceutical acceptable salts, wherein at least one of said salts is a phosphate salt and ,optionally (vi) a pharmaceutical acceptable buffer. Such a formulation is particularly suitable for freeze -drying. The present invention also relates to the corresponding dry product, as well as its preparation process. The present invention also relates to a reconstituted material comprising said dry product , which can be administered to a patient in need thereof. Such formulation and reconstituted material are useful as vaccines , preferably for the treatment and/or the prevention of cancers , infectious diseases and/or autoimmune disorders.
