Timetable still unclear for promising virus vaccines
Once drug is approved, Canada has agreement for 20 million doses
The completion of human trials on one of the leading COVID-19 vaccine candidates has ratcheted up speculation about when Canadians might be able to start rolling up their sleeves. Pfizer and BioNTech announced Wednesday they had finished the final round of human trials on their COVID-19 vaccine candidate — testing they say found the vaccine to be 95 per cent effective with no serious safety concerns.
After a promising early look at results last week, the experimental vaccine is now the first to complete the clinical testing process, having been tested on more than 40,000 people at 150 sites scattered across the United States, Germany, Turkey, South Africa, Brazil and Argentina since July.
The results still must be peerreviewed, which means independent scientists look at the data before the results are published.
U.S. company Moderna, which is using similar technology to Pfizer, has also announced promising early results for its vaccine candidate in recent days, though its testing is ongoing.
Pfizer said it hopes to submit to the U.S. Food and Drug Administration for “emergency use” approval within days; but for Canadians, it will be Health Canada that has the final say on whether or not to approve this vaccine for use, after a review process that has already begun.
Before the vaccine is approved, federal scientists will go through all of the testing results, ask any questions they have and make a decision based on whether they conclude the dose is both safe and effective against coronavirus.
If the vaccine passes approval, Canada has an advance-purchase agreement for 20 million doses.
Ontario Health Minister Christine Elliott said the province is gearing up for the expected vaccine. “We are expecting that we will receive shipments from both Pfizer and Moderna,” Elliott said Wednesday at Queen’s Park.
Though there has been no confirmation on the point from the federal government, an Alberta health ministry official told the Star recently that vaccines, once available, will be handed out to provinces based on population.
“The doses for Canada — we expect to receive four million doses between January and March of the Pfizer vaccine, two million for Moderna — of which we anticipate that we (in Ontario) will receive 1.6 million of Pfizer and 800,000 of Moderna,” Elliott said.
When asked directly to confirm the dates and numbers, federal Health Minister Patty Hajdu would only say it was “really exciting” that Canada is well-positioned to receive millions of doses from both companies.
“There are a number of steps to go through before we actually get to the point of distribution, including the regulatory review with Health Canada to ensure the safety of both vaccines.”
If true, six million doses arriving early next year would be a significant amount, says Dr. Prabhat Jha, an epidemiologist and professor of global health at the University of Toronto, but significant questions remain about who would get them.
To put the number in context, he points to the World Health Organization, which estimates it would take 4.3 billion doses to vaccinate all the seniors, health-care workers and people with high-risk conditions in the world. (That number assumes two doses per person and 15 per cent wastage.)
Jha notes that, roughly adjusting for population, Canada would need about 20 million doses to do the same, so this number would get us almost a third of the way there.
Canada’s National Advisory Council on Immunization has released a list of priority groups, which are roughly in line with WHO guidelines, but the final distribution decisions will be up to the provinces and territories.
“Getting excited about six million doses sounds great,” he said. “But we need to think about who it would be delivered to.”
While any vaccine will need a stamp of approval from Health Canada, the department has taken steps to expedite the approval process.
The federal government has made what’s called a “rolling submission” an option for companies working on the COVID-19 vaccine. Through this process, rather than waiting until all testing is done to walk it over to federal government scientists, a company can share things such as safety data and test results as they go. Pfizer and BioNTech applied for a rolling submission last month.
Still, an exact timeline for vaccine delivery remains unclear. Prime Minister Justin Trudeau has said he hopes to have a vaccine available in as early as the first quarter of next year.
According to Pfizer, its results show that its vaccine, which requires two doses, is 95 per cent effective beginning 28 days after the first shot.
The Pfizer results suggest good news for seniors: Experts had worried that vaccines tend to be less effective in older adults, but Pfizer says the efficacy in those over 65 has also been over 94 per cent.
The dose was “well tolerated” by the thousands of volunteers, according to the company’s statement. The only adverse event, noted in more than two per cent of people, was fatigue (3.8 per cent) and headache (two per cent).
The company expects to produce as many as 50 million doses in 2020 and as many as 1.3 billion doses by the end of 2021.
Although this vaccine has raised eyebrows for the cold temperatures in which it must be stored, Pfizer said it is “confident” in its “experience, expertise and existing cold-chain infrastructure.”
Pfizer said it has developed specially designed shipping containers that use dry ice to keep the temperature around -70 C. The containers can also be used as storage for 15 days, if the dry ice is refreshed.
Elliott acknowledged there will be challenges with the vaccines currently seen as frontrunners.
“There are significant issues with respect to the Pfizer vaccine in particular,” she noted, referring to the temperature at which it must be stored.
“People do have to receive two doses 21 days apart. This is a major logistical challenge, but we have an entire group within the Ministry of Health right now that are planning for that as soon as we receive those shipments from the federal government.”