A study to evaluate efficacy, safety, and immunogenicity of mRNA-1273 vaccine in adults aged 18 years and older to prevent COVID-19

The Phase 3 clinical trial, taking place in the USA, will evaluate the efficacy and safety of the candidate vaccine mRNA-1273 

Primary objective:  

  • To demonstrate the efficacy of mRNA-1273 to prevent COVID-19 
  • To evaluate the safety and reactogenicity of 2 injections of mRNA-1273 given 28 days apart


Type of studyInterventionalclinical trial phase III


Treatment testedVaccine


Countries: USA


Number of sites100


Sample size30,000


Study participants:  Participants (males and females 18 years of age or older at time of consent), who are at risk of SARS-CoV-2 infection with no known history of SARS-CoV-2 infection


Study status Recruiting

More information


Last updated: September 2020


Note that study-related documents posted on the COVID-19 Clinical Research Coalition (COVID-19 CRC) website have been shared by coalition members for information. Some may have been approved by Ethics Review Boards and others may still be in draft form. Documents posted here may have been further amended before being used in the conduct of the respective trials they were designed for. It is recommended that users review these documents carefully and, if they plan to use them, adapt them appropriately for their intended use. The COVID-19 CRC and its members cannot accept any liability for any claim, loss or damages as a result of any reliance placed on, or use of, these documents.