On Nov. 4, 2022, Moderna announced that Health Canada had authorized the use of its BA.4/BA.5 Omicron-targeting bivalent COVID-19 booster vaccine, mRNA-1273.222, as a booster dose for active immunization against COVID-19 caused by the SARS-CoV-2 virus in individuals 18 years of age and older.

The 50 ﾵg booster dose of mRNA-1273.222 includes 25 ﾵg of mRNA encoding for the spike protein of BA.4/BA.5 and 25 ﾵg encoding for the original strain of the SARS-CoV-2 virus.