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. Health Canada’s authorization of mRNA-1273.222 was based both on pre-clinical data for mRNA-1273.222 as well as clinical data from a Phase 2/3 trial studying mRNA-1273.214. A Phase 2/3 clinical trial for mRNA-1273.222 is fully enrolled and currently underway, with initial data expected later the year.