A(H7N9) VLP Antigen Dose-Ranging Study With Matrix-M1™ Adjuvant

This is a randomized, observer-blinded, placebo-controlled trial in adults 18 to 64 years old. Randomization will be stratified by age (18 to 49 years and 50 to 64 years) and by prior influenza immunization within the past three months. Subjects 18 to 49 years of age will comprise \~67% of subjects in each treatment group, and the balance will comprise subjects 50 to 64 years. Each subject will receive two identical IM doses of test article at a 21-day interval (Day 0 and Day 21), in alternate deltoids. For each subject, study follow-up will span approximately 385 days total, or approximately 13 months from the first dose.