The federal government has reached a deal to receive an additional 20 million doses of COVID-19 vaccines this spring while provinces look at whether to stretch out the timeline between shots to give as many people a first injection as possible.
The expert committee that advises the Public Health Agency of Canada on vaccinations released new recommendations Tuesday saying it was safe to increase the interval between shots to six weeks, longer than the three or four weeks vaccine makers used in their clinical trials.
Cecely Roy, a spokesperson for Procurement Minister Anita Anand, said that any updated guidance on the use of COVID-19 vaccines in Canada will be brought to negotiations with drug makers as Canada continues to press for accelerated deliveries of vaccines. Earlier Tuesday, Ms. Anand told a news conference that she had been hearing from manufacturers that it’s important to stick to the recommended schedule.
The more that provinces and territories adhere to this strengthens Canada’s position at the negotiating table on earlier deliveries, she added.
Both Pfizer and Moderna said late Tuesday they are reviewing the findings from the National Advisory Committee on Immunization (NACI).
“Pfizer’s primary concern remains with respecting the dosing interval authorized by Health Canada (two doses administered 21 days apart),” said Christina Antoniou, the director of corporate affairs for Pfizer Canada.
The committee’s non-binding advice was published in the midst of a global scientific debate about how best to deploy a limited supply of vaccines against the coronavirus. In Canada, Quebec has already decided to follow the lead of Britain and stretch the interval to at least 12 weeks, while British Columbia has said it intends to offer second doses at the five-week mark, within the NACI guidelines.
Other provinces are trying to roll out the vast majority of their first doses quickly, while relying on future shipments for second doses they hope to inject as close to the vaccine-makers’ timelines as possible.
Mathematical modelling shows that more infections and severe cases of COVID-19 could be averted if the maximum number of first doses is injected as swiftly as possible, said Caroline Quach-Thanh, chair of the NACI.
“Given the vaccine scarcity, what we’ve said is, ‘use your first doses and then aim, with the vaccine supply chain, to give your second dose within the next six weeks,’ " she said. “Keep it as close as possible to the three or four weeks if you’re able, but you have some leeway.”
Dr. Quach-Thanh, an infectious diseases physician and epidemiologist at Montreal’s Sainte-Justine Hospital, said NACI set a cut-off of six weeks because there are no data for delaying the interval any longer for the Pfizer-BioNTech or Moderna vaccines approved for use in Canada. She said some of the vaccine recipients in the trials received their second doses a few weeks late.
However, data from the trials show the efficacy of the first injection tops 90 per cent shortly before the second dose is due, Dr. Quach-Thanh added. The booster shot is necessary for longer-lasting protection, she said.
Marc-André Langlois, Canada Research Chair in molecular virology and intrinsic immunity at the University of Ottawa, sees merit in delaying second doses by a few weeks as Canada races to stay ahead of the fast-spreading variants of the coronavirus first identified in South Africa and Britain.
But delaying second doses by two or three months, longer than NACI recommends, poses some risks, he said.
“By not having an optimal immune response, you’re not quenching that infection properly,” Dr. Langlois said, noting that could lead to the “possible generation of mutant [variants] that would be resistant to vaccine.”
With the arrival of additional doses in the spring, public health experts are looking at the case for vaccinating as many people as possible now.
Mr. Trudeau said Tuesday the 20 million doses will arrive in April or May, meaning the country will now have 80 million doses of vaccines arriving this year. Although Canada had already ordered enough doses to vaccinate every adult twice, the extra 20 million doses coming in the spring will allow the country to access them faster.
He also reiterated that the government is on track to ensure every Canadian who wishes to receive a vaccine will be able to do so by September.
Ms. Anand said the government currently has enough vaccinations “to at least perform the initial vaccination.”
Ottawa hopes to move up the schedule even more with the approval of other vaccines, she added.
Health Canada is working on the review of two additional vaccines from Johnson & Johnson and AstraZeneca.
Meanwhile, provinces including Ontario, Quebec, Manitoba, British Columbia and Alberta have called on Ottawa to ensure there are is a steady, reliable flow of vaccines.
Alberta Premier Jason Kenney, who has criticized the federal government for the pace of the vaccine rollout, said Tuesday that the government is looking into signing its own deals with vaccine makers to boost supply to the province.
Mr. Kenney said the federal government has signed exclusive Canadian rights to purchase several vaccines, including those produced by Pfizer-BioNTech, Moderna and AstraZeneca, which is already approved in Britain. He said his government is now looking at other prospective vaccines whose manufactures haven’t already signed deals with Ottawa.
“There is a reason that the provinces have agreed to come together under federal procurement, because in a scramble where every country in the world is trying to obtain these vaccines, obviously having purchasing power matters a lot,” he told Global News Radio in Calgary.
“But if there are smaller producers that have not signed contracts with the government of Canada, I have asked whether we can get into those systems.”
Mr. Kenney said Alberta expects to run out of vaccines – meaning that deliveries won’t be able to keep up with the province’s capacity to administer vaccines – by next week.
Ms. Anand said that vaccine companies are very willing to do negotiations and contracts with the federal government because they are buying in bulk for the country.
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