Kinetic fusion assay data outlined here indicate that the hemagglutinin (HA) viral spike glycoprotein, purified from influenza virions and reconstituted in magnetic erythrocyte vehicles, maintains its fusogenic properties thus determining the integration of the delivery system with the cytoplasmatic membranes of target cells notwithstanding the dimension (8 micron) of the erythro-magneto-HA virosomes. Here, ART4 is linked to influenza.