On Nov. 16, 2020, Moderna announced that the independent, NIH-appointed Data Safety Monitoring Board (DSMB) for the Phase 3 study of mRNA-1273, its vaccine candidate against COVID-19, had informed Moderna that the trial had met the statistical criteria pre-specified in the study protocol for efficacy, with a vaccine efficacy of 94.5%.

This study, known as the COVE study, enrolled more than 30,000 participants in the U.S. and was conducted in collaboration with the National Institute of Allergy and Infectious Diseases.