Compared with the Pfizer COVID-19 vaccine, the Moderna COVID-19 vaccine has a slightly lower risk of COVID-19 outcomes, including documented SARS-CoV-2 infection, symptomatic COVID-19, and COVID-19-related hospitalization, intensive care unit admission, and death, over a 24-week period, according to a team of researchers. This pattern was consistent for periods when Alpha or Delta were the predominant variant.