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

Vaccine. 2011 Oct 19;29(45):8049-59. doi: 10.1016/j.vaccine.2011.08.042. Epub 2011 Aug 22.


The avian influenza H5 virus epizootic continues to cause zoonosis with human fatalities, highlighting the continued need for pandemic preparedness against this subtype. This study evaluated the tolerability and immunogenicity of a Matrix M™ adjuvanted virosomal H5N1 vaccine in a phase I clinical trial. Sixty healthy adults were vaccinated intramuscularly with two doses of influenza H5N1 (NIBRG-14) virosomal vaccine alone (30 μg haemagglutinin (HA)) or 1.5, 7.5 or 30 μg HA formulated with 50 μg Matrix M™ adjuvant. The antibody response was analysed by haemagglutination inhibition (HI), microneutralisation (MN) and single radial haemolysis (SRH) assays. The vaccine was well tolerated in all groups but injection site pain was more frequently observed in the Matrix M™ adjuvanted groups. The vaccine elicited homologous and heterologous H5N1-specific antibody responses and the Matrix M™ adjuvanted formulations met all the EU regulatory criteria. In conclusion, Matrix M™ adjuvant was well tolerated and augmented the antibody response allowing considerable dose sparing down to 1.5 μg HA.

Publication types

  • Clinical Trial, Phase I
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic / administration & dosage*
  • Adjuvants, Immunologic / adverse effects*
  • Adult
  • Antibodies, Viral / blood
  • Chemistry, Pharmaceutical
  • Drug-Related Side Effects and Adverse Reactions / epidemiology
  • Female
  • Hemagglutination Inhibition Tests
  • Hemolysis
  • Humans
  • Immunization, Secondary / methods
  • Influenza A Virus, H5N1 Subtype / immunology*
  • Influenza Vaccines / administration & dosage
  • Influenza Vaccines / adverse effects*
  • Influenza Vaccines / immunology*
  • Injections, Intramuscular
  • Male
  • Middle Aged
  • Neutralization Tests
  • Pain / epidemiology
  • Vaccination / methods
  • Vaccines, Virosome / administration & dosage
  • Vaccines, Virosome / adverse effects
  • Vaccines, Virosome / immunology


  • Adjuvants, Immunologic
  • Antibodies, Viral
  • Influenza Vaccines
  • Vaccines, Virosome