Safety Assessments
ADVERSE EVENTS
Solicited local and systemic adverse events were collected via electronic diary for 7 days following each injection. Participants were assessed for all unsolicited adverse events from the first dose through 28 days after the second dose (day 49); serious adverse events, adverse events of special interest, and medically attended adverse events related to vaccination are to be collected from the first dose until the end of the study, which will occur approximately 2 years after enrollment. This report only includes data until the precrossover, placebo-controlled part of the study (April to September 2021).