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

Traffic will be diverted through Radium along highways 93 and 95 as a part of the closures. (Claire Palmer photo)
Extended closures to Trans-Canada Highway announced east of Golden this fall

It’s the second round of extended closures as a part of Phase 4 of the Kicking Horse Canyon Project

FILE – Perry Bellegarde, National Chief of the Assembly of First Nations, takes part in an event on Parliament Hill in Ottawa on Tuesday, July 7, 2020. THE CANADIAN PRESS/Sean Kilpatrick
Indigenous Peoples Day must be a ‘call to action’, says Assembly of First Nations chief

Discovery of children at Kamloops residential school site must lead to change, Perry Bellegarde says

This undated file photo provided by Ernie Carswell & Partners shows the home featured in the opening and closing scenes of The Brady Bunch in Los Angeles. Do you know the occupation of Mike Brady, the father in this show about a blended family? (Anthony Barcelo/Ernie Carswell & Partners via AP, File)
QUIZ: A celebration of dad on Father’s Day

How much do you know about famous fathers?

Fruit farmers in the Okanagan and Creston valleys are in desperate need of cherry harvesters amid COVID-19 work shortages. (Photo: Unsplash/Abigail Miller)
‘Desperate’ need for workers at Okanagan cherry farms

Fruit farmers are worried they’ll have to abandon crops due to COVID-19 work shortages

A tent housing a mobile vaccination clinic. (Interior Health/Contributed)
Over 5K jabbed at Interior Health mobile COVID-19 vaccine clinics

The clinics have made stops in more than 40 communities since launching last week

The border crossing into the United States is seen during the COVID-19 pandemic in Lacolle, Que. on February 12, 2021. THE CANADIAN PRESS/Paul Chiasson
VIDEO: Border quarantine to soon lift for fully vaccinated Canadians

Eligible travellers must still take multiple COVID-19 tests

Chilliwack secondary school’s principal is apologizing after a quote equating graduation with the end of slavery in the U.S. was included in the 2020-2021 yearbook. (Screenshot from submitted SnapChat)
B.C. student’s yearbook quote equates grad to end of slavery; principal cites editing error

Black former student ‘disgusted’ as CSS principal apologizes for what is called an editing error

Skeena MLA Ellis Ross. (Photo by Peter Versteege)
BC Liberal leadership candidate condemns ‘senseless violence’ of Okanagan church fires

Skeena MLA Ellis Ross says reconciliation isn’t about revenge for past tragedies

A coroner’s inquest will be taking place at the Capitol Theatre in Port Alberni for the next week. (ELENA RARDON / ALBERNI VALLEY NEWS)
Teen B.C. mom who died following police custody recalled as ‘friend to many’

Police sent Jocelyn George to hospital after intoxication had gone ‘beyond the realm’ of normal detox

FILE - In this Nov. 29, 2020, file photo, Las Vegas Raiders defensive end Carl Nassib leaves the field after an NFL football game against the Atlanta Falcons in Atlanta. Nassib on Monday, June 21, 2021, became the first active NFL player to come out as gay. Nassib announced the news on Instagram, saying he was not doing it for the attention but because “I just think that representation and visibility are so important.” (AP Photo/John Bazemore, File)
Nassib becomes first active NFL player to come out as gay

More than a dozen NFL players have come out as gay after their careers were over

Photograph By MICHAEL POTESTIO.KTW
Former Kamloops security gaurd wants job back after kicking incident caught on video

Rick Eldridge quit when a video surfaced of him kicking a man outside a facility for homeless

Penticton Indian Band Chief Greg Gabriel speaks to the Sacred Hearts Catholic Church burning down early Monday morning, June 21, 2021. (Monique Tamminga Western News)
Penticton band chief condemns suspicious burning of 2 Catholic churches

Both Catholic church fires are deemed suspicious, says RCMP

People participated in a walk to honour the 215 children found at a former Kamloops residential school, as well as residential school survivors. (Twila Amato/Black Press Media)
Kelowna marks National Indigenous Peoples’ Day with walk to remember Kamloops 215

“Let’s speak the truth and deal with the truth, and heal.”

COVID-19 daily cases reported to B.C. public health, seven-day moving average to June 17, 2021. (B.C. Centre for Disease Control)
B.C.’s COVID-19 infections drop to 90 on Sunday, 45 Monday

Pandemic spread dwindles as 77% of adults receive vaccine

Most Read