OTTAWA — Canada on Wednesday become only the second Western country to approve a coronavirus vaccine, a week after Britain did so and a day before U.S. regulators will meet to consider taking that step, opening the possibility that Canadians will start being inoculated next week.
The regulatory agency Health Canada approved the same vaccine, created by the American company Pfizer and a German firm, BioNTech, that was authorized in Britain and is up for a decision in the United States. Canada’s move marks another milestone in the global fight against a pandemic that has killed more than 1.5 million people, continues to spread rapidly and has driven the world into a deep recession.
Health Canada said that it had completed a rigorous, independent review of the data from clinical trials on the vaccine’s safety and effectiveness, which involved tens of thousands of people — the same kind of scrutiny applied by the U.S. Food and Drug Administration. British regulators, in giving emergency approval, relied largely on Pfizer’s own analysis of that data, which is the standard approach in much of the world. Bahrain approved the same vaccine on Friday.
“It’s a testament to the work of regulators internationally,” said Dr. Supriya Sharma, the chief medical adviser at Health Canada, the regulator. “It’s an exceptional day for Canada.”
The go-ahead means that Canadians could receive the vaccine — which requires two doses, weeks apart — before Americans do, though Pfizer is based in the United States. That is likely to aggravate President Trump, who has demanded faster action by the F.D.A. and was angry that Britain, which began inoculating people on Tuesday, had acted before the United States.
The first shipments to Canada, of 249,000 doses, will come from a plant in Belgium, officials said.
Other vaccines are close behind in the approval processes in Europe and North America, and still others are in development. Vaccines developed in Russia and China are already in use — the United Arab Emirates gave full approval to a Chinese inoculation on Wednesday — though clinical trials on them are still underway.
Canada has ordered 6 million doses from Pfizer, and millions of doses of other potential vaccines from other companies, but the rollout will take months.
A Canadian official said on Wednesday that Pfizer would ship the first vaccines on Friday and they were expected to arrive on Monday. While the vaccine must be prepared before injections, the official said that they may start as early as the middle of next week. The vaccine must be kept at extremely cold temperatures until within a few days of use, making transportation and storage a challenge.
Dr. Sharma said that the vaccine had been subjected to the same degree of scrutiny as any previous drug or vaccine. But to accelerate the process, Health Canada reviewed data from clinical trials and manufacturing tests as the data was being generated, allowing for a “rolling review.” In the past, the department only opened reviews when all trials and tests were complete.
She said that the final data needed for approval arrived late Tuesday evening and was reviewed overnight, which allowed the approval to go forward.
Canada’s review, she said, supported Pfizer’s finding that the vaccine was 95 percent effective.
When asked why her group was able to approve the vaccine ahead of the F.D.A. in the United States, Dr. Sharma said, apparently jokingly, “we’re just better.”
She added, “We’re not in a race with any other regulator, we’re trying to beat the virus.”
For now, Health Canada has approved the vaccine only for people over the age of 16; it is waiting for further data from Pfizer before approving it for children.