Safety assessment
≤28
ADVERSE REACTIONS, ADVERSE EVENTS
The primary safety objective was to evaluate the safety and reactogenicity of 50 µg mRNA‑1273.222 when administered as a second booster dose. Safety assessments included solicited local and systemic adverse reactions ≤7 days and unsolicited adverse events ≤28 days post booster administration, and serious adverse events, adverse events leading to discontinuation from study vaccine and/or participation, medically attended adverse events and adverse events of special interest from day 1 through the entire study period (~6 months).