The study is a randomized, double-blind, and approved vaccine-controlled Phase II booster study. It will evaluate the immunogenicity and safety of one dose of SCTV01C or SCTV01E as booster compared with one dose of Sinopharm inactivated COVID-19 vaccine or one dose of Commirnaty as booster. The study will also evaluate the immunogenicity and safety of 2-dose vaccinations (1-dose of SCTV01C and 1-dose of SCTV01E, or 2-dose of SCTV01E, or 1-dose of Sinopharm inactivated COVID-19 vaccine and 1-dose of SCTV01E, 1-dose of Comirnaty and 1-dose of SCTV01E).
The objective of study is to evaluate the immunogenicity and safety of SCTV01C or SCTV01E as booster compared with Sinopharm inactivated COVID-19 vaccine as booster. The study will also evaluate the immunogenicity and safety of 2-dose vaccinations.