Whose COVID-19 vaccines are coming to Canada, and when? How well do they work? Everything you need to know

The Globe and Mail

A researcher works in a lab run by Moderna Inc., one of the companies working on an experimental COVID-19 vaccine.

Moderna Inc./Handout via REUTERS

During a week when cases of COVID-19 are surging toward ever higher numbers in Canada, it’s hard to imagine more welcome news than that coming from the makers of two leading vaccine candidates. Both say their vaccines are effective and safe based on the data from two large-scale clinical trials conducted in the United States. But as public-health experts are quick to point out, it is not vaccines but vaccination that will ultimately stop the pandemic. With a rollout of vaccines expected to begin in Canada in the new year, here is what those experts are saying about what we know, what we don’t and what we can expect in the months ahead.

Watch: Ivan Semeniuk explains how Canadian authorities are assessing COVID-19 vaccine candidates while trials are under way, but it’s likely high-risk people will be prioritized for receiving any vaccine first. The Globe and Mail

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How good are the vaccines Canada has arranged to buy?

Canada was among the countries that moved quickly to ink deals for some of the leading vaccine candidates, based on recommendations from a federally appointed task force. So far, it looks like those bets are paying off. Canada has a lock on 20 million doses of vaccine produced jointly by Pfizer Inc. and Germany’s BioNtech. This week, that vaccine was the first to pass through a Phase 3 clinical trial with data showing it to be 95-per-cent effective.

The impressive score is based on just 170 people among the 45,000 participants in the trial who got COVID-19 within one month of getting their first shot. Only 5 per cent of those 170 cases occurred in people who received the vaccine. The rest received a placebo instead.

The good news was further bolstered by equally strong interim results from a vaccine produced by Moderna in Cambridge, Mass. Moderna’s vaccine is also destined for Canada with an order of up to 56 million doses. The two orders combined are enough to vaccinate every Canadian with the required two doses.

However, while Pfizer applied to the U.S. Food and Drug Administration for an emergency-use authorization on Friday and Moderna is expected to follow suit, problems could still arise as more data come in.

Both rely on a new technology. Unlike traditional vaccines, which work by delivering a weakened virus or viral proteins to help train the body’s immune system, the Pfizer and Moderna vaccines consist of tiny particles that carry genetic instructions in the form of RNA, which the body takes up and uses to generate copies of viral proteins.

Gary Kobinger, a Laval University researcher who developed the vaccine for Ebola, said he is happy that Canada has also purchased five other COVID-19 vaccines, including those based on more proven technologies. There’s a good chance that most of them will work now that two have been shown to perform well, he said.

“I think it looks good for a lot other vaccines to see some level of protection,” he said, in part because, despite their differences, the vaccines are all based on the same idea: presenting or coaxing the body to manufacture copies of the coronavirus spike protein – the knobby protrusion that surrounds the virus and allows it to infect cells.

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When will the vaccines be approved in Canada?

Health Minister Patty Hajdu watches Chief Public Health Officer Theresa Tam at a Nov. 20 news conference in Ottawa.

Justin Tang/The Canadian Press

The most important unknown remains safety. Pfizer and Moderna have said in news releases that their vaccines have produced no serious adverse effects, but detailed data have yet to be released and examined as part of the approval process by Health Canada officials, as well as for a third vaccine, developed by AstraZeneca and Oxford University. Since October, all three have been undergoing regulatory review through a “rolling submission,” which allows evaluation by regulators to begin before all the data are gathered.

While this approach is intended to advance the process more quickly, the COVID-19 vaccines will still have to meet the same safety standards that apply to all vaccines that Health Canada approves, said Supriya Sharma, the department’s chief medical adviser. “This is what our vaccine reviewers do day in and day out,” Dr. Sharma said. “They make these assessments of the data around benefits, risks and uncertainties and determine whether or not something should be authorized.”

She added that there is no way to be sure how long the process will take until all the data are in, but said that authorization could come as early as January for one or more of the vaccines under review.

Even then, the data from clinical trials involving tens of thousands of participants will not be enough to detect safety issues that could be significant but rare. These may become apparent only after millions of people have been given the vaccine. This is why monitoring of the vaccines will continue long after the approval process, as it would for any vaccine or drug, Dr. Sharma said.

Another mystery is whether the vaccines can actually stop the spread of COVID-19. Since the coronavirus can be transmitted by people before they show symptoms of the disease, including those who never show symptoms at all, it will be difficult to learn from clinical trials alone whether the vaccines reduce transmission, or simply turn more people into asymptomatic spreaders. The upshot is that until more is known, masks and physical distancing are likely to remain recommended precautions.

Finally, public-health agencies have no way to know yet how long a vaccine will confer immunity to COVID-19. “It’s early days, but I’m optimistic,” said Tal Zaks, chief medical officer for Moderna. “Immunity should hold for many months … but we will continue to follow [clinical trial] participants for two years and monitor the degree to which they’re protected.”

How will the vaccines be distributed?

A DHL worker loads dry ice into 'Envirotainers' at a facility for the shipment of vaccines and medical supplies in Chicago.

DHL/Handout via REUTERS

While many details are still being worked out, one thing is clear: Previous vaccination programs will pale in comparison to what is about to be attempted. “This will be one of the most complicated and important mass health interventions in our lifetime,” said Kumanan Wilson, a senior scientist at the Ottawa Hospital Research Institute.

Public Service and Procurement Canada, which handles the multiple orders, could begin receiving the first batches of vaccines early next year. Once they arrive, the vaccines will fall under the purview of the Public Health Agency of Canada and will be distributed to each province and territory. Discussions around how this will happen are now under way between governments.

Pfizer and Moderna have said they expect to produce tens of millions of doses by the end of this year and hundreds of millions for the global market in 2021.

There are physical complications to transporting and storing the vaccines, particularly RNA vaccines, which are not stable at room temperature. This creates the need for a “cold chain” that allows the vaccines to be shipped to their many destination points without losing their potency. Pfizer’s vaccine must be stored at -70 C, which requires specialized equipment, while Moderna has said commercial freezers will do for its vaccine. Acuitas Therapeutics in Vancouver licenses its technology to make the tiny lipid nanoparticles that contain the RNA in the Pfizer vaccine. President and CEO Thomas Madden said the two vaccines are similar enough that Pfizer’s will likely turn out to be just as viable as Moderna’s under the same storage conditions.

Dr. Kobinger said people can feel encouraged by the fact the latest Ebola epidemic was declared over this week in the Democratic Republic of Congo, thanks in part to a vaccine that has similar cold-chain requirements to Pfizer’s COVID-19 vaccine. “It’s much easier to have cold storage in Canada, even at -70, than it is in the middle of the tropical forest in Africa,” he said.

Another hurdle will simply be keeping track of who has been vaccinated and who hasn’t – something that will be all the more challenging because multiple vaccines will be available and most will require two doses. Differences between provincial systems for vaccination record keeping will further complicate the task.

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Who will get the vaccines first?

A nurse welcomes a man to a Montreal COVID-19 testing clinic on Nov. 9.

Paul Chiasson/The Canadian Press/The Canadian Press

Public-health officials are increasingly optimistic that COVID-19 vaccines will be available to most Canadians as early as next summer. Between now and then, the number of available doses will be limited and some population groups are expected to be prioritized.

Those groups have already been identified in recommendations by an independent panel appointed by the federal government.

The high-priority groups include those who are at elevated risk of severe illness and death from COVID-19, including seniors and those with health complications. They also include health care workers and others who are part of the pandemic response, as well as providers of essential services and people who are working in settings where physical distancing and other preventive measures are challenging or who live in places where access to health care is reduced, including Indigenous communities.

Caroline Quach, an infectious-diseases specialist and microbiologist at the University of Montreal who chairs the committee, said that more details on how those priority groups should be ordered could be made public as early as next week. However, provincial and territorial governments will ultimately have to decide who fits into the groups and in what order vaccinations will be offered.

Whether someone is placed in a priority group or not, the federal government has made clear that a vaccine will eventually be made available to everyone who wants one at no cost.

A potentially more serious question is how many will choose not to be vaccinated. This will have an impact on efforts to control the pandemic and on the return to normal life.

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Ève Dubé, a professor of medical anthropology at Laval University, has been conducting weekly surveys on attitudes toward vaccination in Quebec since March. She said that while about 75 per cent of those surveyed during the first wave of the pandemic said they were willing to be vaccinated, that number fell by 15 to 20 per cent by the fall.

Good public communication will be essential to the success of the vaccination effort, she said. Her message to health agencies: “Be transparent. Be clear about what we know, what we don’t know and what we’re doing to fill the gaps.”

BY THE NUMBERS The next curve: Three stages of a vaccine rollout

Like other countries, Canada will face limited supplies of COVID-19 vaccines at first and higher-risk groups will be given priority ahead of the general population.​ While different priority groups have not yet been ranked, this chart shows a plausible plan for a vaccine rollout.

*Dotted line indicates uncertainty about

duration of vaccine immunity

Constrained supply

 

Highly targeted administration required to achieve coverage in priority populations

Health care professionals and first responders

 

People with high-risk conditions

 

Older adults, including those in long-term care homes

LARGE NUMBER OF DOSES AVAILABLE

Likely sufficient supply meet demand

 

Supply increases access

 

Broad administration network required

Non-health-care essential workers

 

People working in settings where prevention is difficult

 

Communities with reduced access to health care

 

People most likely to transmit to high-risk groups

CONTINUED VACCINATION, SHIFT TO ROUTINE

STRATEGY

Likely excess supply

 

Broad administration network for increased access

All others who did not have access in previous phases

THE GLOBE AND MAIL, SOURCE: CDC; NACI

Like other countries, Canada will face limited supplies of COVID-19 vaccines at first and higher-risk groups will be given priority ahead of the general population.​ While different priority groups have not yet been ranked, this chart shows a plausible plan for a vaccine rollout.

*Dotted line indicates uncertainty about duration of vaccine immunity

Constrained supply

 

Highly targeted administration required to achieve coverage in priority populations

Health care professionals and first responders

 

People with high-risk conditions

 

Older adults, including those in long-term care homes

LARGE NUMBER OF DOSES AVAILABLE

Likely sufficient supply meet demand

 

Supply increases access

 

Broad administration network required

Non-health-care essential workers

 

People working in settings where prevention is difficult

 

Communities with reduced access to health care

 

People most likely to transmit to high-risk groups

CONTINUED VACCINATION, SHIFT TO ROUTINE STRATEGY

Likely excess supply

 

Broad administration network for increased access

All others who did not have access in previous phases

THE GLOBE AND MAIL, SOURCE: CDC; NACI

Like other countries, Canada will face limited supplies of COVID-19 vaccines at first and higher-risk groups will be given priority ahead of the general population.​ While different priority groups have not yet been ranked, this chart shows a plausible plan for a vaccine rollout.

DOSES AVAILABLE AT DIFFERENT STAGES

LARGE NUMBER OF DOSES AVAILABLE*

CONTINUED VACCINATION, SHIFT TO ROUTINE

STRATEGY*

*Dotted line indicates uncertainty about duration of vaccine immunity

Likely sufficient supply meet demand

 

Supply increases access

 

Broad administration network required

Constrained supply

 

Highly targeted administration required to achieve coverage in priority populations

Likely excess supply

 

Broad administration network for increased access

Health care professionals and first responders

 

People with high-risk conditions

 

Older adults, including those in long-term care homes

All others who did not have access in previous phases

Non-health-care essential workers

 

People working in settings where prevention is difficult

 

Communities with reduced access to health care

 

People most likely to transmit to high-risk groups

THE GLOBE AND MAIL, SOURCE: CDC; NACI

How RNA vaccines work

The COVID-19 pandemic has led to the debut of RNA vaccines, which are designed to harness the body’s own cells to imitate a viral infection and train the immune system to attack the coronavirus. RNA vaccines, which are faster to produce, have emerged as front-runners, but other types of vaccines that may ultimately be less costly or provide other advantages are also being developed.

RNA VACCINE

Vaccine delivers RNA sequence inside a protective envelope

RNA enters host cell and provides instructions to make coronavirus spike protein

RNA enters host cell and provides instructions to make coronavirus spike protein

Presence of spike protein stimulates production of antibodies and other responses

The immune system is now primed to recognize the coronavirus and generate antibodies that prevent the virus from attaching to host cells via the ACE2 receptor.

MURAT YÜKSELIR AND IVAN SEMENIUK /

THE GLOBE AND MAIL

The COVID-19 pandemic has led to the debut of RNA vaccines, which are designed to harness the body’s own cells to imitate a viral infection and train the immune system to attack the coronavirus. RNA vaccines, which are faster to produce, have emerged as front-runners, but other types of vaccines that may ultimately be less costly or provide other advantages are also being developed.

RNA VACCINE

Vaccine delivers RNA sequence inside a protective envelope

RNA enters host cell and provides instructions to make coronavirus spike protein

RNA enters host cell and provides instructions to make coronavirus spike protein

Presence of spike protein stimulates production of antibodies and other responses

The immune system is now primed to recognize the coronavirus and generate antibodies that prevent the virus from attaching to host cells via the ACE2 receptor.

MURAT YÜKSELIR AND IVAN SEMENIUK /

THE GLOBE AND MAIL

The COVID-19 pandemic has led to the debut of RNA vaccines, which are designed to harness the body’s own cells to imitate a viral infection and train the immune system to attack the coronavirus. RNA vaccines, which are faster to produce, have emerged as front-runners, but other types of vaccines that may ultimately be less costly or provide other advantages are also being developed.

RNA VACCINE

Vaccine delivers RNA sequence inside a protective envelope

RNA enters host cell and provides instructions to make coronavirus spike protein

RNA enters host cell and provides instructions to make coronavirus spike protein

Presence of spike protein stimulates production of antibodies and other responses

The immune system is now primed to recognize the coronavirus and generate antibodies that prevent the virus from attaching to host cells via the ACE2 receptor.

MURAT YÜKSELIR AND IVAN SEMENIUK / THE GLOBE AND MAIL

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