This vaccine model differs fundamentally from the current influenza virus vaccines, as it does not contain the variable regions of the virus hemagglutinin and hence does not induce hemagglutination inhibition antibodies that serve as surrogate markers for protection. In order to demonstrate the potential efficacy of the Multimeric-001, an alternative assay was employed, in which the lysis of MDCK cells infected with different virus strains was shown, with the involvement of the complement mechanism. The humoral and cellular responses suggest a cross-immunity of the vaccine toward influenza virus strains regardless of mutations. These results corroborate the protective effect of the vaccine, previously shown in animals. Larger-scale studies are under way to further substantiate the safety and efficacy of the vaccine candidate.