This study is a randomized, double-blind, single-center, controlled phase III clinical trial in children aged 36-71 months, and bridging trial between agegroup of 6-35 and 36-71 months. The purpose of this study is to evaluate the immunogenicity and safety of the experimental EV71 vaccine in children aged 36-71 months. The primary objective of this study is to evaluate the non-inferiority of experimental EV71 vaccine compared to the control EV71 vaccine in children aged 36-71 months, and the non-inferiority of EV71 vaccine used in children aged 36-71 months compared to 6-35 months. The secondary objective is to evaluate the safety of the experimental vaccine used in children aged 36-71 months. The experimental vaccine is manufactured by Sinovac Biotech Co., Ltd, and the control vaccine is manufactured by Institute of Medical Biology Chinese Academy of Medical Sciences. 600 children aged 36-71 months will be randomly assigned in to receive the experimental vaccine or control vaccine, and 300 children aged 6-35 months will receive the experimental vaccine.
The purpose of this study is to evaluate the non-inferiority of experimental EV71 vaccine compared to the control EV71 vaccine in children aged 36-71 months, to evaluate the non-inferiority of EV71 vaccine used in children aged 36-71 months compared to 6-35 months. The experimental vaccine was manufactured by Sinovac Biotech Co., Ltd, and the control vaccine was manufactured by Institute of Medical Biology Chinese Academy of Medical Sciences.