A Phase 3b/4, Open-label Study to Assess the Immunogenicity and Safety of mRNA COVID-19 Variant-containing Vaccine Formulations
The purpose of this study is to investigate the immunogenicity and safety of mRNA COVID-19 variant-containing vaccine formulations against the vaccine-matched variants and newly emerged variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
• mRNA-1273.167 and mRNA-1273.712: Previously vaccinated adults aged ≥18 years
• mRNA-1273.251: Participants ≥65 years of age, ≥12 to \<65 years of age, or ≥6 months to \<12 years of age with at least 1 risk factor for severe outcomes from COVID-19.
• mRNA-1273.261: ≥65 years of age at the time of signing the informed consent or ≥18 to \<65 years of age at the time of signing the informed consent with at least 1 risk factor for severe outcomes from COVID-19.
• Able to comply with study procedures based on the assessment of the Investigator.
• Female participants of childbearing potential may be enrolled in the study if the participant fulfills all the following criteria:
‣ Has a negative pregnancy test at the Screening Visit and on the day of vaccination prior to vaccine dose being administered on Day 1.
⁃ Has practiced adequate contraception or has abstained from all activities that could result in pregnancy for at least 28 days prior to the first dose.
⁃ Has agreed to continue adequate contraception through 28 days following vaccine administration.