Anticipated delays for the next month to shipments of doses from Pfizer/BioNTech — one of the two COVID-19 vaccines currently approved for use in Canada — are upending vaccination programs from coast to coast.
The delays, reportedly the result of production issues in Belgium, highlight the logistical challenges that lie ahead as a global vaccination effort unfurls.
But they also raise the question of when Canada will have more than two vaccines on tap.
The vaccines from Pfizer-BioNTech and U.S.-based Moderna have been hailed around the world for their performance in clinical trials and the speed at which they were developed. They’re major scientific success stories, but they are only two of the dozens of vaccines still under development.
Canada’s plan has long been to lock down not one or two vaccines but, hopefully, a portfolio of them.
To that end, federal officials have inked deals with seven different vaccine manufacturers that represent four different “platforms,” or ways of making vaccines.
“The more vaccines that we have at our disposal, the better it will be and the more quickly and the more equitably we can use vaccination to try and prevent disease going forward,” said Nicole Basta, an associate professor of epidemiology at McGill University who runs an online vaccine tracker that has charted the progress of various vaccines since early in the pandemic.
Of particular interest at the moment is the vaccine developed by British-Swedish multinational AstraZeneca in partnership with Oxford University. Their vaccine was approved by the United Kingdom in late December and shots started rolling out across the pond early in the new year. But Canada is still assessing the vaccine.
Ontario Premier Doug Ford has called on the federal government to approve it, a call repeated by his Alberta counterpart, Jason Kenney, last week.
“Of course we want candidates to maintain high standards, but if there was ever an emergency, this is it. I hope that they have Health Canada operating around the clock to ensure the fastest possible approval times,” Kenney said.
The federal regulatory body is currently reviewing both AstraZeneca and another vaccine made by Janssen, which is Johnson & Johnson’s pharmaceutical arm.
Health Minister Patty Hajdu told reporters last week that a decision was expected on AstraZeneca in the “near future,” though a spokesperson for Health Canada would not confirm that Monday, saying they could not provide a “definite timeline” for when the reviews might be done.
In the meantime, delays in the supply of the Pfizer vaccine — which represented the lion’s share of Canada’s expected deliveries — are already being felt.
Toronto’s first non-hospital vaccination clinic, which opened Monday at the Metro Toronto Convention Centre, will have to shut down Friday. The goal had been to vaccinate 250 health-care workers a day, for at least six weeks.
Canada was supposed to get four million Pfizer doses by the end of March, but the company is cutting deliveries in half for the next month. Federal officials say they’ll get bigger deliveries after that and still expect to have received four million doses by the end of the first quarter.
Toronto medical offer of health Dr. Eileen de Villa said deliveries of the Pfizer vaccine are expected to catch up through February and March.
Basta says it’s not unusual for different regulators to approve vaccines at different times. Still, she says having multiple vaccines at our disposal will be an important part of ending the pandemic.
“There are even more that are still in Phase 3 trials that we expect to find out soon about how well those protect, and how safe they will be,” she said. (Phase 3 is the final stage of human testing.)
“There’s a lot of hope that we’ll continue to add to the arsenal that we have to fight COVID-19 with vaccines.”
All vaccines try to prevent disease, but there are a lot of ways to do that, and public health officials hoped that different vaccines would allow experts to target certain doses to particular segments of the population in order to achieve the best results.
In some ways, that has already been the case in Canada, as the territories have been given priority access to the Moderna vaccine, which is much easier to transport than the Pfizer alternative.
More vaccines also mean more doses.
Federal officials have said they’re relying on Health Canada to approve more vaccines if they’re to meet the goal of getting most people in the country vaccinated by the end of September.
So where are the other five vaccines that Canada has agreed to purchase?
AstraZeneca
How many doses Canada has an agreement for: 20 million
Who makes it: AstraZeneca is a British-Swedish pharmaceutical company that partnered with the University of Oxford.
In a nutshell: This vaccine is expected to be cheaper and easier to distribute than currently available shots, which bodes well for the developing world, but has raised concerns about what dosing regime to use.
What do we know: This appears set to become the third vaccine approved in Canada. The fact that it can be stored at normal refrigerator conditions means it will likely be much easier to transport.
Although Canada has not made public how much it is paying for vaccines, this one is expected to be cheaper for everyone as the company has pledged not to profit from its vaccine during the pandemic.
Results for Phase 3 testing were published in an academic journal in early December, and found that the vaccine was between 70 and 90 per cent effective depending on the specific dosing regime. Researchers have faced criticism since it was revealed that an early mistake led to some volunteers getting a smaller first dose than intended, although that ended up appearing to make the vaccine more effective.
This vaccine has been approved by the U.K., but its regulator has instructed it to be distributed in two full doses, citing a lack of data about the reduced dose plan.
Current status: Under review by Health Canada.
Janssen
How many doses Canada has an agreement for: As many as 38 million
Who makes it: Janssen is the pharmaceutical arm of Johnson & Johnson. Its headquarters are in Belgium.
In a nutshell: This is the only vaccine Canada is betting on that would require just one dose.
What do we know: The company published some results from its early Phase 1 and 2 trials last week that suggested most volunteers generated an immune response and that the dose was “generally well-tolerated.”
Although it’s too early to know how effective it will be, Moncef Slaoui, chief adviser for the American vaccine development program, dubbed Operation Warp Speed, said last week it could show efficacy of 80 per cent or higher, according to Reuters.
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According to the company’s website, it’s expecting to release some information from the final stage of human testing in late January, though it notes that timing is approximate.
Current status: Under review by Health Canada
Sanofi and GlaxoSmithKline
How many doses Canada has an agreement for: As many as 72 million
Who makes it: Sanofi is a French pharmaceutical company, while GSK is headquartered in England.
In a nutshell: The companies announced a setback in December after their vaccine didn’t work in seniors as well as they had hoped.
What we know: It was a big disappointment but researchers remained “confident and committed,” according to the news release in December.
Although an early clinical study found that the vaccine triggered an immune response in many volunteers that was comparable to people who’d recovered from COVID-19, the immune response in older adults was “low,” according to the statement.
At the time, the companies said they planned a new trial with a tweaked formula that would start in February.
Current status: delayed
Novavax
How many doses Canada has an agreement for: As many as 76 million
In a nutshell: An American-made vaccine that is now in the final stage of human testing.
Who makes it: Novavax is an American company based in Maryland.
What we know: This vaccine moved into the final stage of human testing just before the holidays, and is currently looking to enrol 30,000 volunteers at 115 sites in the United States and Mexico, according to the American National Institutes of Health.
“The launch of this study — the fifth investigational COVID-19 vaccine candidate to be tested in a Phase 3 trial in the United States — demonstrates our resolve to end the pandemic through development of multiple safe and effective vaccines,” Anthony S. Fauci said in a release at the time.
Current status: Recruiting for a Phase 3 study
Medicago
How many doses Canada has an agreement for: As many as 76 million
Who makes it: This is Canada’s leading homegrown candidate, as Medicago is based in Quebec.
In a nutshell: This vaccine is made in Canada, and it’s made from plants.
What do we know: Medicago is taking a unique approach to vaccine making. It is using a cousin of a tobacco plant to make what are called virus-like particles that are designed to trick your body into thinking they’re coronavirus particles — but they’re not.
The hope is that they’ll be a close enough match to teach your body to generate an immune response when it sees the real thing.
“It will self-assemble in a way that it will look, under an electron microscope, like the virus. It’s pretty similar, but it’s not the virus, it’s not infectious, it cannot replicate or induce any disease,” Nathalie Landry, Medicago’s executive vice-president of scientific and medical affairs, told the Star in November.
The federal government has given the company $173 million to supply as many as 76 million doses of its vaccine — should it be successful — and to build a manufacturing facility in Quebec City.
Current status: Recruiting for a phase 2 and phase 3 study
https://news.google.com/__i/rss/rd/articles/CBMidWh0dHBzOi8vd3d3LnRoZXN0YXIuY29tL25ld3MvY2FuYWRhLzIwMjEvMDEvMTgvb25lLWRvc2UtaXMtZGVsYXllZC1idXQtd2hlcmUtYXJlLWNhbmFkYXMtb3RoZXItY292aWQtMTktdmFjY2luZXMuaHRtbNIBeWh0dHBzOi8vd3d3LnRoZXN0YXIuY29tL2FtcC9uZXdzL2NhbmFkYS8yMDIxLzAxLzE4L29uZS1kb3NlLWlzLWRlbGF5ZWQtYnV0LXdoZXJlLWFyZS1jYW5hZGFzLW90aGVyLWNvdmlkLTE5LXZhY2NpbmVzLmh0bWw?oc=5
2021-01-19 01:28:58Z
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