Evaluation of a virosomal H5N1 vaccine formulated with Matrix M™ adjuvant in a phase I clinical trial

► Phase I clinical trial evaluating the tolerability and immunogenicity of a Matrix M™ adjuvanted virosomal H5N1 vaccine. ► Vaccination elicited homologous and heterologous H5N1-specific antibody responses. ► Two doses of Matrix M™ adjuvanted 1.5 μg HA virosomal met all the EU regulatory criteria. ► Matrix M™ adjuvant was well tolerated and augmented the antibody response allowing considerable dose sparing down to 1.5 μg HA. ► Comparison of the antibody responses by haemagglutination inhibition (HI), microneutralisation (MN) and single radial haemolysis (SRH) serological assays.