Health Canada Approves New Moderna Vaccine for COVID-19

A pharmacist holds up a vial of the bivalent Moderna COVID-19 vaccine in a file image. Ringo Chiu/AFP via Getty Images

Health Canada has approved a new Moderna COVID-19 vaccine for all Canadians over the age of six months based on preliminary clinical data.

Health Canada posted authorization of the new shot on Sept. 12, saying the vaccine targets an Omicron subvariant called XBB.1.5.

Shots recommended are as follows: One dose for ages five years and older, and as a booster for ages six years and older. For children between six months and four years old, the government suggests they have two doses if they have not previously been given a COVID shot.

On Sept. 12, Health Canada officials delivered a technical briefing on the new Moderna vaccine. A spokeswoman said the vaccine was authorized “after an independent and thorough scientific review for safety, efficacy, and quality, including a review of data from several studies of the primary series and booster doses of the VX vaccine collected over the past two years.”

“After assessing all the data, we’ve concluded that there is strong evidence showing that the benefits of this vaccine outweigh the potential risks,” she said, adding that the shot was “anticipated to provide a robust immune response.”

Moderna, in a news release issued Aug. 17, stated its own “preliminary” clinical trial data “confirm its updated COVID-19 vaccine generates robust immune response in humans.”

“These results suggest that Moderna’s updated COVID-19 vaccine may effectively target the expected circulating variants of COVID-19 during the upcoming vaccination season,” stated the pharmaceutical giant.

Side Effects

In its safety information, Moderna said the vaccine should not be given to individuals with a known history of severe allergic reaction to any component in its vaccine.

“Postmarketing data demonstrate increased risks of myocarditis and pericarditis, particularly within 7 days following the second primary series dose or first booster dose,” said the company. The 72-page fact sheet lists warnings and precautions. The highest risk for myocarditis and pericarditis, it cites, is in males 18 to 24 years old.

The company said “information is not yet available about potential long-term” after effects. It also states, “The vaccines may not protect all vaccine recipients.”

Adverse reactions to the vaccine listed by Moderna for six to 36 months of age include: “injection site erythema, pain and swelling; axillary (or groin) swelling/tenderness, fever, irritability/crying, loss of appetite and sleepiness.”

In ages 37 months and older, adverse reactions include all of the above plus,” arthralgia, chills, fatigue, headache, myalgia, nausea/vomiting, and rash.”

Health Canada said it is actively reviewing submissions from Pfizer Biotech and Novavax, both looking for authorization of two new versions of COVID vaccines.

NACI Advice

The National Advisory Committee on Immunization (NACI) updated its guidance on the use of COVID vaccines in the fall of 2023, saying it continues to recommend that those who have already received a COVID vaccine obtain one dose of XBB.1.5 formulation if it has been six months since a previous shot or known infection.

NACI continues to recommend COVID vaccines for adults 65 and older, long-term care home residents, individuals with underlying medical conditions, pregnant women, members of indigenous communities and “racialized and other equity-deserving communities,” plus those who provide “essential community services.”

Syringes of Moderna COVID-19 vaccines at a vaccination site in Los Angeles on Feb. 16, 2021. Apu Gomes/AFP via Getty Images

The organization says there are still COVID variants circulating in Canada, with the most prevalent being one called XBB.1.9.2.

“Individuals vaccinated with the updated XBB.1.5-containing COVID-19 vaccine are expected to benefit from a better immune response against currently circulating strains, compared to earlier formulations. Preliminary clinical data demonstrated that a booster dose of a monovalent XBB.1.5-containing COVID-19 vaccine generated similar immune responses against XBB* sub-lineages XBB.1.5, XBB.1.16 and XBB.2.3.2,” wrote NACI.

It said that it had yet not determined if there should be an “annual COVID-19 vaccination program” similar to the annual flu drives.

The U.S. Food and Drug Administration (FDA) has also cleared new COVID-19 vaccines, including one from Moderna and Pfizer. The FDA approved the vaccines for people aged 12 and older. Regulators granted emergency authorization of the shots for people aged 6 months to 11 years.

The vaccines also target XBB.1.5, a subvariant already largely displaced by newer strains of the Omicron virus, according to the U.S. Centers for Disease Control and Prevention.

The Canadian Press, Naveen Athrappully, and Zachary Stieber contributed to this report.