A Heterologous Prime-boost Study to Evaluate Immunogenicity and Safety of mRNA-1273 With MVC-COV1901 in Adults

The primary objective of the study is to evaluable the safety and to demonstrate the immunogenicity of heterologous prime-boost (mRNA-1273, MVC-COV1901), compared to homologous prime-boost (mRNA-1273), with an interval of 8-12 weeks, This study also assesses the safety and tolerability of the study intervention and explores the immunogenicity by the antigen-specific immunoglobulin, the immunogenicity against the VoCs, the antigen specific cellular immune response, as well as the potential efficacy of study intervention in preventing COVID-19.