Trial vaccine and placebo
STERILE
PTX-COVID19-B mRNA vaccine, manufactured by PT (lot number: PTX-CB-003), was supplied as a sterile solution (0.2 mg/mL). The mRNA encoding for 1273 amino acid of SARS-COV-2 whole length S protein was formulated in lipid nanoparticles as the final drug product. The placebo was injectable saline solution (sodium chloride 0.9%). Vaccine doses were diluted with injectable saline to reach the 16-µg and 40-µg doses. The 100-µg doses did not require dilution. Vaccine and placebo were administered intramuscularly into the upper arm deltoid muscle of the non-dominant side in a 0.5 mL dose with a 25G needle.