Procedures
ADVERSE EVENTS
Participants received two intramuscular injections of either a 10-µg vaccine or a placebo (an adjuvant-only preparation) at 2-week intervals. FAKHRAVAC inactivated vaccine was made of SARS-CoV-2 strains isolated from the oropharyngeal Swabs of Iranian hospitalized patients replicated using Vero cells (Cat. # 88020401), a WHO-approved cell line for vaccine production. Aluminum sulfate was used as the adjuvant. The participants' immunogenicity responses and the occurrence of solicited and unsolicited adverse events were assessed over the study period of up to 6 months (see Additional file 