This study a randomized, double-blinded, phase Ⅳ clinical trial of COVID-19 vaccine (Vero cell), Inactivated.The purpose of this study is to evaluate the safety and immunogenicity of booster vaccination using high-dosage or medium-dosage of COVID-19 vaccine (Vero cell), Inactivated in populations who have completed primary immunization 5-9 months.A total of 340 subjects who have completed primary immunization using two-dose Coronavac® 5-9 months were be enrolled.All of subjects were be randomly divided into two groups in a 1:1 ratio to receive high-dosage or medium-dosage of COVID-19 vaccine (Vero cell), Inactivated.
This is a randomized, double-blinded, phase Ⅳ clinical trial of COVID-19 vaccine (Vero cell), Inactivated manufactured by Sinovac Life Sciences Co. , Ltd. The purpose of this study is to evaluate the safety and immunogenicity of booster vaccination using high-dosage or medium-dosage of COVID-19 vaccine (Vero cell), Inactivated in populations who have completed primary immunization 5-9 months