This is the clinical trial including an open-label, single-arm Phase I study and a subsequent randomized, blind, placebo-parallel controlled Phase II study to evaluate the safety, immunogenicity and immune persistence of COVID-19 mRNA vaccine in healthy people aged 18-60 years and ≥18 years respectively, whose locations or circumstances put them at appreciable risk of acquiring COVID-19 and/or SARS-CoV-2 infection.
This clinical trial is a phase I/II clinical trial to evaluate the safety, immunogenicity and immune persistence of COVID-19 mRNA vaccine in healthy people aged 18 years and above.