On Sept. 28, 2023, Pfizer and BioNTech that Health Canada had authorized the companies’ Omicron XBB.1.5-adapted monovalent COVID-19 vaccine (COMIRNATY Omicron XBB.1.5) for ages 6 months and older. For children 6 months through 4 years of age the updated vaccine was authorized for administration as a three-dose series in those without a history of completion of a COVID-19 primary vaccination course, or as a single dose for those with a history of completion of a COVID-19 primary vaccination course.

The authorization of is based on the full body of previous clinical, non-clinical, and real-world evidence supporting the safety and efficacy of the Pfizer-BioNTech COVID-19 Vaccines. Further, the application included pre-clinical data on the neutralization potential of serum antibodies induced by the updated monovalent COVID-19 vaccine against multiple XBB-related sublineages, including XBB.1.5, XBB.1.16, XBB.2.3 and EG.5.1 (Eris).

Pfizer and BioNTech continue to monitor emerging SARS-CoV-2 strains and continue to conduct studies to monitor the vaccine’s effectiveness, including the recently emerged Omicron BA.2.86 (Pirola) variant and the globally dominant EG.5.1 (Eris) subvariant.