Immune Response to SARS-CoV-2 after a Booster of mRNA-1273: An Open-Label Phase II Trial

Investigators reported the results of the open-label, non-randomized part B of a Phase II trial in which they evaluated the safety and immunogenicity of a booster injection of 50 µg of the COVID-19 vaccine mRNA-1273 in 344 adult participants immunized 6–8 months earlier with a primary series of two doses of 50 µg or 100 µg of mRNA-1273.