A vial of AstraZeneca vaccine is seen at a mass COVID-19 vaccination clinic in Calgary, Alta., on April 22, 2021. THE CANADIAN PRESS/Jeff McIntosh

A vial of AstraZeneca vaccine is seen at a mass COVID-19 vaccination clinic in Calgary, Alta., on April 22, 2021. THE CANADIAN PRESS/Jeff McIntosh

AstraZeneca expiry change based on science but communication is key: experts

Medical advisor said decision made after AstraZeneca submitted data supporting the change

Many immunologists and infectious disease experts are rushing to convince Canadians that extending the expiration date on some Oxford-AstraZeneca doses is a normal and scientifically sound decision.

Health Canada said Saturday it had approved adding another month to the shelf life of two lots of Oxford-AstraZeneca vaccine that were due to expire Monday.

Ontario asked the company if the change could happen to save up to 45,000 doses that were expiring, but the decision affects remaining doses from the two affected lots in every province. Fewer than 100,000 doses are left from those two lots.

Health Canada’s chief medical adviser, Dr. Supriya Sharma, said in an interview with The Canadian Press Monday that the decision was made after AstraZeneca submitted data supporting the change last week.

That included the results of testing doses from the two lots that were expiring, and modelling data from the company that showed the doses would remain stable for at least the next month.

“We’ve been really clear that we’re making decisions based only on science and evidence, and this is no exception,” Sharma said.

But the decision to adjust the expiration date at the 11th hour on the weekend led many Canadians to express frustration and concern about whether it was truly being made because of science, or because of a policy failure to use the doses in time.

“The feedback I’m getting is this idea that it was done out of desperation,” said Timothy Caulfield, the Canada Research Chair in health law and policy at the University of Alberta.

“That’s the way it looks from the outside. It’s a really good example of why context matters.”

Pharmacologist Sabina Vohra-Miller, founder of the science communication website Ambiguous Science, said it is not uncommon at all for companies to get calls from pharmacies asking if a patient can use their drug beyond the expiration.

“Most of the time when these expiry dates are extended, people don’t get to know about it,” she said.

She said vaccines and other medications are tested constantly to determine how they perform in various scenarios, including past their expiration.

“For all we know we might next year find out that based on long-term shelf life studies that in fact the vaccines are totally OK for an entire year, so maybe for future batches the expiry date will be a year,” she said. “We just don’t know this yet, because these vaccines are so new.”

AstraZeneca, Pfizer-BioNTech and Moderna all have six-month life spans at the moment, if stored properly. That means in a fridge for AstraZeneca, an ultralow temperature freezer for Pfizer and a normal freezer for Moderna.

The Johnson & Johnson vaccine, the only other one authorized by Health Canada though it’s not in use here yet, can be stored frozen for up to two years.

Sharma said there are no other requests to adjust expirations for COVID-19 vaccines, but also noted that doses expiring is not a big issue when people still want more doses than we have in our supply.

It was an issue for these doses because Ontario had paused the use of AstraZeneca while awaiting more data on the risk of vaccine-induced blood clots. It is now using them only for second doses but didn’t decide to proceed with second doses early enough to avoid the risk the expiring doses would go to waste.

Sharma said she can understand the perception that the decision was made out of desperation but said that is not something Health Canada would do.

“I mean, I think it would have been better if the submission came to us earlier,” she said. “It only came to us on May 27. And so we looked at it as soon as we could. If that data did not support the extension, we would have said no.”

Caulfield said communicating scientific decisions in a pandemic is really hard, but doing it well is also critical.

“When I first heard this story my immediate reaction was anything that invites doubt, anything that injects more skepticism into the calculus, for those that are sitting on the fence (about getting vaccinated) is problematic,” he said.

More than two-thirds of eligible Canadians are now vaccinated with at least one dose. Caulfield said Canada is getting close to what he calls the “hesitancy hurdle” where the people not yet vaccinated may need some convincing.

The impact of framing how we talk about vaccines matters “more and more” right now, he said.

Dr. Allison McGeer, an infectious disease consultant at Mount Sinai Hospital in Toronto, said the change to the vaccine expiry is a normal part of the process and should not be viewed with alarm.

“Yeah, it will come at the last minute but that’s that’s a pandemic thing,” she said. “I have absolute faith in Health Canada, that they know what they’re doing, and that we have solid processes for managing this and extending expiry dates. This isn’t anything out of the ordinary.”

—Mia Rabson, The Canadian Press

RELATED: Health Canada extends expiry of thousands of AstraZeneca shots by another month

Coronavirusvaccines

Just Posted

File photo
Leduc RCMP request assistance to identify armed robbery suspect

Leduc RCMP are looking for male responsible for an armed robbery at Super Car and RV Wash in Leduc.

Alberta Premier Jason Kenney arrives at the 2021 budget in Edmonton on Thursday, Feb. 25, 2021.THE CANADIAN PRESS/Jason Franson
Alberta launches COVID vaccine lottery with million-dollar prizes to encourage uptake

The premier says the lottery will offer three prizes worth $1 million a piece, as well as other prizes

The City of Red Deer sits at 249 active cases of the virus, after hitting a peak of 565 active cases on Feb. 22. (Black Press file image)
Red Deer down to 119 active COVID-19 cases

Province identifies 179 new cases Saturday

Member Terry Parsons’ custom built track vehicle.
Forestburg’s Area 53 Racetrack gears up for action-packed season

Site will also host a portion of the ‘Miles of Mayhem’ event in July

Sabrina Wilde in front of a recently purchased monster truck. Submitted.
Thorsby business women a finalist for 2021 Alberta Women’s Entrepreneurship Award

Sabrina Wilde with Lone Wolf Mechanical is a finalist for the entrepreneurial award.

Canadian Prime Minister Justin Trudeau participates in a plenary session at the G7 Summit in Carbis Bay, England on Friday June 11, 2021. THE CANADIAN PRESS/Adrian Wyld
Canada donating 13M surplus COVID-19 vaccine doses to poor countries

Trudeau says the government will pay for 87 million shots to be distributed to poor countries

Calgary Stampeders’ Jerome Messam leaps over a tackle during second half CFL western semifinal football action in Calgary, Sunday, Nov. 15, 2015.THE CANADIAN PRESS/Jeff McIntosh
CFL football will be played this summer in Canada

Governors vote unanimously in favour to start the ‘21 campaign on Aug. 5

Citizenship Minister Marco Mendicino holds a press conference in Ottawa on Thursday, Nov. 12, 2020. The federal government is announcing that Indigenous people can now apply to reclaim their names on passports and other government documents. THE CANADIAN PRESS/Sean Kilpatrick
Indigenous people can now reclaim traditional names on their passports and other ID

Announcement applies to all individuals of First Nations, Inuit and Métis background

This undated photo provided by Girl Scouts of New Mexico Trails shows a scout donating cookies to firefighters in Rio Rancho, New Mexico, as part of the Hometown Heroes program. As the coronavirus pandemic wore into the spring selling season, many Girl Scout troops nixed their traditional cookie booths for safety reasons. That resulted in millions of boxes of unsold cookies. (Girl Scouts of New Mexico Trails via AP)
Thinner Mints: Girl Scouts have millions of unsold cookies

Since majority of cookies are sold in-person, pandemic made the shortfall expected

In this artist’s sketch, Nathaniel Veltman makes a video court appearance in London, Ont., on June 10, 2021 as Justice of the Peace Robert Seneshen (top left) and lawyer Alayna Jay look on. THE CANADIAN PRESS/Alexandra Newbould
Terror charges laid against London attack suspect

Crown says Nathaniel Veltman’s four counts of first-degree murder constitute an act of terrorism

Indigenous Services Minister Marc Miller is seen during a news conference, Wednesday May 19, 2021 in Ottawa. THE CANADIAN PRESS/Adrian Wyld
Indigenous child-welfare battle heads to court despite calls for Ottawa to drop cases

Feds are poised to argue against two Canadian Human Rights Tribunal rulings

The Great Ogopogo Bathtub Race has been held in Summerland as a fundraising event. Do you know which Canadian city introduced this sport? (Black Press file photo)
QUIZ: A summer’s day at the water

How much do you know about boats, lakes and water?

Flowers and cards are left at a makeshift memorial at a monument outside the former Kamloops Indian Residential School to honour the 215 children whose remains are believed to have been discovered buried near the city in Kamloops, B.C., on Monday, May 31, 2021. THE CANADIAN PRESS/Darryl Dyck
‘Pick a Sunday:’ Indigenous leaders ask Catholics to stay home, push for apology

Indigenous leaders are calling on Catholics to stand in solidarity with residential school survivors by not attending church services

“They will never be forgotten, every child matters,” says Sioux Valley Chief Jennifer Bone in a video statement June 1. (Screen grab)
104 ‘potential graves’ detected at site of former residential school in Manitoba

Sioux Valley Dakota Nation working to identify, repatriate students buried near former Brandon residential school

Most Read