Licensing the first reduced, 6 µg dose whole virion, aluminum adjuvanted seasonal influenza vaccine – A randomized-controlled multicenter trial

Z. Vajó, L. Kalabay, Peter Vajo, Gergely Balaton, N. K. Rózsa, Peter Torzsa

Research output: Contribution to journalArticle


Introduction: Shortages of vaccine supplies repeatedly occur, limiting our abilities to prevent influenza. Therefore, increasing production volume remains a priority. The presently licensed seasonal influenza vaccines contain 15 µg of viral hemagglutinin per strain in adult, and up to 60 µg in elderly patients. Decreasing the amount of viral parts while maintaining efficacy is one way of increasing production capacity. Methods: This was multicenter, stratified (18–60 years and >60 years of age), prospective, randomized, double-blind, active-controlled, parallel-arm, non-inferiority clinical trial, conducted in the European Union, involving 1206 patients. We used hemagglutination inhibition assay to assess the immunogenicity of a newly developed, whole virion, seasonal trivalent influenza vaccine, containing 6 µg hemagglutinin per strain (FluArt, Hungary) and to assess whether it is non-inferior to the presently licensed vaccine containing 15 µg hemagglutinin per strain. Safety and tolerability of both vaccines were assessed based on EMEA guidelines. Results: The reduced dose vaccine containing 6 µg of hemagglutinin per strain was safe and non-inferior to the currently licensed 15 µg vaccine, not only in adult, but also in elderly patients, according to the immunogenicity criteria by the FDA and EMEA (seroconversion, seroprotection and post/pre vaccination GMT ratios), and it fulfilled all applicable licensing requirements for both age groups. Conclusions: Based on the results, the reduced dose vaccine was licensed in the EU member state Hungary and safely administered in over 1.5 million cases so far. The amount of viral hemagglutinin needed can be reduced by using a whole virion vaccine with aluminum phosphate adjuvants. Registration: This study was registered by the European Clinical Trials Database, EudraCT, number: 2011-003314-16.

Original languageEnglish
Pages (from-to)258-264
Number of pages7
Issue number2
Publication statusPublished - Jan 7 2019



  • Dose
  • Influenza
  • Trial
  • Vaccine

ASJC Scopus subject areas

  • Molecular Medicine
  • Immunology and Microbiology(all)
  • veterinary(all)
  • Public Health, Environmental and Occupational Health
  • Infectious Diseases

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