Health Canada approves updated Moderna vaccine targeting Omicron subvariant

As the United States makes significant moves to get an updated COVID-19 vaccine to pharmacies nationwide, Canadian health officials have approved an updated Moderna booster for everyone over six months.

Health Canada made the announcement ahead of a scheduled press conference and COVID-19 briefing.

The new vaccine targets the XBB.1.5 variant of the virus that causes COVID-19. Health Canada received Moderna’s submission for its new COVID-19 vaccine on June 29, 2023.

The health regulator said it’s “actively reviewing submissions from Pfizer” seeking authorization of their COVID-19 vaccine targeting the Omicron subvariant.

“According to the product label, individuals five years of age and older should receive one dose, regardless of their COVID-19 vaccination history,” a Health Canada spokesperson said.

“Children between six months and four years of age should receive two doses if they have not been previously vaccinated with a COVID-19 vaccine, or one dose if they have been previously vaccinated with one or more doses of a COVID-19 vaccine.”

Health officials said an updated vaccine composition with a revised construct encoding the spike protein for “prominent variants of concern” may provide a better antibody response against circulating and emerging COVID-19 variants, such as XBB.1.5.

“Based on the totality of the information, the benefit-risk profile for a dose of Spikevax XBB.1.5 is considered favourable in individuals six months of age and older.”

The U.S. approved updated COVID-19 vaccines from Pfizer and Moderna on Monday, hoping to rev up protection against the latest coronavirus strains and blunt any surge this fall and winter.

Canada is one of 12 countries currently dealing with the Omicron variant BA.2.86, which has been detected in wastewater samples in additional countries, the U.S. Centre of Disease Control and Prevention (CDC) said. The BA.2.86 variant was first discovered a few weeks ago in British Columbia.

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Canadian health officials referenced a new vaccine study conducted on mice. It revealed that when administered as a two-dose primary series, the monovalent and bivalent formulations of the XBB.1.5-variant matched vaccines elicited “robust binding antibody titers” against the spike protein as well as neutralizing antibody titers against both XBB.1.5 and XBB.1.16 strains.

BA.2.86, which health experts have named “Pirola,” was first detected in late July. Early data show that BA.2.86 has 34 more mutations in its spike protein than BA.2, which drove a global COVID-19 surge in 2022.

It’s unclear whether BA.2.86 will cause a surge in infections this fall as the CDC said there is no evidence that this variant is causing more severe illness.

Canada’s National Advisory Committee on Immunization (NACI) has published updated information showing that since the fall of 2022, national surveillance data has shown a surge in COVID-19 cases from late September to November 2022 and a lesser wave in December 2022 and January 2023.

NACI said beginning in the fall of 2023, for those previously vaccinated against COVID-19, they recommend a dose of the new formulation of the COVID-19 vaccine for individuals over six months if it has been at least six months from the previous vaccine dose or known infection (whichever is later).

For booster doses, NACI previously recommended that at least one booster dose be offered to all adults 18 years of age and over and adolescents 12 to 17 years of age who are at increased risk of severe illness.

Data shows vaccine protection wanes over time, and COVID-19 continually churns out new variants that can dodge prior immunity. It’s been a year since the last time the vaccines were tweaked.

With files from CityNews Parliament Hill reporter Cormac MacSweeney and The Associated Press