Interim guidance on the use of bivalent Omicron containing COVID-19 vaccines for primary series

Bivalent Omicron-containing mRNA COVID-19 vaccines are authorized as booster doses for those 5 years of age and older, but there is currently no bivalent vaccine authorized for a primary series in any age group or as a booster dose for those less than 5 years of age. Several regulatory submissions for the use of bivalent mRNA COVID-19 vaccines as a primary series are currently under review by Health Canada. Many original monovalent mRNA vaccines will no longer be available in the coming months, and PHAC has asked NACI to consider how jurisdictions can ensure COVID-19 product options for the primary series are available to all recommended populations.

This includes consideration of off-label use of bivalent vaccines using age-based dosages that are different from those currently authorized for the primary series with the original mRNA COVID-19 vaccines. As regulatory submissions progress over the summer, vaccine schedules and/or dosages may change for some age groups. New formulations of COVID-19 vaccines that reflect changes in circulating Omicron subvariants may also become available in the fall of 2023.