After a months-long review, Health Canada regulators today approved the COVID-19 vaccine from Oxford University-AstraZeneca for use in Canada — clearing the way for millions more inoculations in the months ahead.
The department’s regulators concluded the shot has an efficacy rate of 62 per cent and have authorized it for use in all adults 18 and older.
“Overall, there are no important safety concerns, and the vaccine was well tolerated by participants,” the decision reads.
Canada has secured access to 22 million doses of the AstraZeneca vaccine, most of which are slated to arrive in the second and third quarters of this year.
Public Services and Procurement Minister Anita Anand has said the government is trying to negotiate faster delivery of these doses now that new, more contagious COVID-19 variants are taking hold in Canada.
Health Canada also has authorized the vaccine manufactured by the Serum Institute, which has partnered with AstraZeneca to make that company’s COVID-19 product at its facilities in India.
The Serum Institute, which is working with Mississauga, Ont.-based Verity Pharmaceuticals, will send 500,000 doses of its vaccine “within weeks,” Prime Minister Justin Trudeau said. He added that 1.5 million doses from Serum will arrive in “the coming months.”
With these new doses coming from Serum, Canada now stands to receive about 6.5 million doses of the AstraZeneca, Moderna and Pfizer vaccines by the end of March. That’s enough to fully vaccinate just over 3.2 million people.
“This is very encouraging news. It means more people vaccinated, and sooner. Because for AstraZeneca, just like we were for Pfizer and Moderna, we are ready to get doses rolling,” Trudeau said.
“Vaccines will keep arriving faster and faster as we head into the spring.”
Some countries — such as France — have restricted the AstraZeneca vaccine to people under the age of 65, even though the World Health Organization insists the product is safe and effective for all age groups. Health Canada said it has no immediate safety concerns for those 65 and older.
‘Promising evidence’
The regulator said the clinical trial results “were too limited to allow a reliable estimate of vaccine efficacy in individuals 65 years of age and older,” but the department was comfortable with approving the shot because of “post-market experience in regions where the vaccine has already been deployed.”
Speaking at a technical briefing today, Dr. Supriya Sharma, Health Canada’s chief medical adviser, conceded there was limited clinical trial data about the efficacy of the shot in people over the age of 65 but said regulators approved it because of “promising evidence from real-world use of the vaccine.”
Other countries — notably Australia, the European Union and the United Kingdom — have authorized AstraZeneca already for use in their jurisdictions.
In a study of vaccine efficacy in Scotland — where both the AstraZeneca and Pfizer products have been in widespread use for weeks — researchers found the AstraZeneca product reduced the risk of COVID-19 hospital admissions by roughly 94 per cent, 28 to 34 days after the first shot. The researchers also warned that the study sample was quite small.
And while the AstraZeneca product was found to be less effective than the Pfizer and Moderna shots already approved, Sharma said there’s no doubt that a dose of this vaccine is better than no dose at all.
While there are risks associated with any vaccine, Sharma said, the benefits of getting an AstraZeneca shot “outweigh their potential risks.”
Sharma said it will be up to the National Advisory Committee on Immunization (NACI) to decide which groups should get each type of vaccine.
She also cautioned Canadians against comparing efficacy rates of the various vaccine products, saying that in the areas that matter most — preventing serious illness, reducing hospitalizations and curbing the number of deaths — “all these vaccines are good.”
“If you look across all the clinical trials of the tens of thousands of people who were involved, the number of cases of people who died from COVID-19 that got vaccines was zero,” Sharma said.
“The number of people that were hospitalized because their COVID-19 disease was so severe was zero. The number of people that died because of an adverse event or effect of the vaccine was zero.”
Health Canada is recommending that the second dose of the AstraZeneca product be administered four to 12 weeks after the first, but Sharma said there is early evidence suggesting it’s best to wait the full 12 weeks to deploy the second shot.
“With an increased interval, the efficacy might be much higher,” she said.
The product was approved in Australia, for example, but regulators there recommended a three-month wait between shots.
Regulator still reviewing 2 other vaccine candidates
Health Canada is still reviewing two other vaccine candidates: one from Johnson & Johnson and another from Novavax.
The U.S. Food and Drug Administration’s vaccines advisory committee will meet today to review the clinical trial data for the Johnson & Johnson vaccine. A final U.S. decision on issuing emergency use authorization (EUA) could come as early as this weekend.
Canada has ordered 10 million doses from Johnson & Johnson with options for up to 28 million more, if necessary. Most of those shots are expected to arrive by the end of September.
While Health Canada regulators are aiming to make a decision on this product on a timeline similar to that of the FDA, Sharma said the department is still collecting some data from the manufacturer and a final decision is not expected this weekend.