A Study to Evaluate the Immunogenicity and Safety of Two Recombinant Protein COVID-19 Vaccines in Population Aged ≥18 Years as Booster Vaccines

Approximately 1,800 participants aged 18 years old and above will be enrolled in this study. 1,350 participants who previously received Sinopharm inactivated COVID-19 vaccine will be enrolled to Cohort 1. 450 participants who previously received mRNA COVID-19 vaccine or previously diagnosed with COVID-19 will be enrolled to Cohort 2.