Influenza is a serious infectious disease exhibiting high mortality in vulnerable populations of all ages, as well as causing significant morbidity in the general population. In 1918, 50 million of the world population was killed by a pandemic Flu. Nowadays, molecule biology has revealed the mechanism of influenza infection, and the awareness of the impact of influenza is increasing, with relevance to the national economic burden and to health care systems. Vaccination is the main tool for influenza prevention. The available, long-used inactivated vaccines are often unsatisfactory and many individuals are reluctant to receive injections. The efficacies of current influenza vaccines range from 70 to 80% to as low as 30% or less, dependent on age and the status of the immune system. WHO has stated that both influenza-specific IgG and IgA antibodies provide protection against clinical diseases and resistance against infection, respectively. Nonetheless, the influenza-specific mucosal IgA responses to vaccines are poor. To meet the medical demand, novel strategies for developing vaccines that activate both mucosal and humoral immunity with improved immunogenicity and efficacy have been put to test.

Mucosal immunization is a vaccination route that offers improved immunity, reduced stress and pain, and may encourage individuals to participate in the vaccination programs. Advagene’s novel nasal influenza vaccine (AD07030) with inactivated influenza antigens in combination with detoxified LTh(αK) has finished phase II study which showed a good safety profile and induced good serum and mucosal immunogenicity. Advagene’s nasal influenza vaccine could be potentially used in medical and health care personals, seniors, children, and immunocompromised patients in the future.