Report of meeting on the development of influenza vaccines with broad spectrum and long-lasting immune responses, February 2004
General Recommendations from Meeting Participants
- Increase awareness of the impact of influenza in general populations so as to increase vaccine demand, providing enhanced incentives for manufacturers to increase vaccine production and invest resources in development of more effective influenza vaccines.
- Expand the understanding of how different components of the immune system induce protection against influenza following immunization. Research on this area should include the elucidation of immunological factors responsible for heterotypic and heterosubtypic protection and specifically the role of CTL-based immunity in humans.
- Conduct clinical studies comparing the efficacy of LAIV and IIV vaccines in children and adults. Include assessments of potential correlates of immunity other than serum anti-HA antibody and of the value of each type of vaccine for induction of heterotypic immunity in the different age groups.
- Continue studies towards development of novel influenza vaccines that target conserved influenza proteins (e.g. M1, M2 and NP).
- Reassess efficacy of DNA-based influenza vaccines by using adjuvants and delivery systems. These vaccines have shown efficacy in pre-clinical studies and are an attractive alternative to the current vaccine technologies because they are easy and fast to manufacture in large scale.
- Conduct additional studies to further evaluate immunogenicity and efficacy of the various adjuvant systems in pre-clinical and clinical studies.
- Compare delivery systems of influenza vaccines – including intramuscular and intranasal, aerosol and transcutaneous routes – for safety, immunogenicity and efficacy of influenza vaccines in controlled clinical trials.
- Improve vaccine-induced immune responses in the elderly. Approaches include further evaluation of higher vaccine dosages and the use of adjuvants.
- Continue attention to both short-term and long-term occurrence of adverse events in clinical trials that evaluate new vaccine approaches.