Sanofi 2017 H7N9 With/Without AS03 in Adults/Elderly

This is a randomized, double-blinded, Phase II study in healthy males and non-pregnant females 19 years and older that is designed to assess the safety, reactogenicity, and immunogenicity of a pre-pandemic 2017 monovalent inactivated influenza A/H7N9 virus vaccine (2017 H7N9 IIV) administered at different dosages given with AS03 adjuvant and phosphate buffered saline (PBS) diluent, with AS03 adjuvant only, and without adjuvant. Eligible subjects will be randomized into 5 study groups, stratified by age. The study will enroll up to 420 individuals 19-64 years old and up to 300 individuals who are 65 years old and older. Study duration is approximately 16 months with subject participation duration approximately 13 months. The primary objectives of this study are: 1) to assess the safety and reactogenicity following receipt of two doses of 2017 H7N9 IIV administered intramuscularly at different dosages approximately 21 days apart given with or without AS03 adjuvant; 2) to assess the serum hemagglutination inhibition (HAI) and neutralizing (Neut) antibody responses following receipt of two doses of 2017 H7N9 IIV administered intramuscularly at different dosages approximately 21 days apart with or without AS03 adjuvant, stratified by age of recipient.