This study is a phase Ⅲ, double-blind, randomized and active-controlled clinical trial to evaluate the safety and immunogenicity of Influenza vaccine (Split virion), Inactivated, Quadrivalent developed by Sinovac Biotech Co., Ltd. (Sinovac-QIV) as compared to a licensed comparator in Chile, Vaxigrip Tetra™ (Vaxigrip Tetra-QIV) in individuals aged 3 years and older. Subjects will be randomized 1:1 to received either Sinovac-QIV or Vaxigrip Tetra-QIV. Vaccine-primed subjects will receive one 0.5ml dose of Sinovac-QIV or Vaxigrip Tetra-QIV on day 0. Vaccine-unprimed subjects will receive two 0.5ml doses of Sinovac-QIV or Vaxigrip Tetra-QIV and day 0 and day 28, respectively. Subjects who are 3-8 years of age had prior receipt of ≥2 doses of influenza vaccine at least 4 weeks apart or who are ≥9 years old are considered vaccine-prime. Subjects who are 3-8 years of age had prior receipt of <2 dose of influenza vaccine are considered vaccine-unprimed.
The purpose of this study is to evaluate the safety and immunogenicity of Influenza vaccine (Split virion), Inactivated, Quadrivalent developed by Sinovac Biotech Co., Ltd. (Sinovac-QIV) as compared to a licensed comparator in Chile and Philippines, Vaxigrip Tetra™ (Vaxigrip Tetra-QIV) in individuals aged 3 years and older.