The Current

No cause for alarm after pause in COVID-19 trial, says co-chair of Canada's Vaccine Task Force

Dr. Joanne Langley says vaccine trials have inbuilt safety measures that will catch any adverse event that may or may not be related to immunization.

Trials have safety measures that will catch any adverse event, even a car accident

A scientist works at Argentina's mAbxience biopharmaceutical company, which is under contract to make an experimental coronavirus vaccine developed by Oxford University and the laboratory AstraZeneca. (Juan Mabromata/AFP/Getty Images)

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AstraZeneca paused trials of a COVID-19 vaccine Tuesday after a patient experienced an "unexplained illness," but that's not a cause for great concern, says the co-chair of the federal government's COVID-19 Vaccine Task Force.

"Every clinical trial has built into it safety measures that will allow you to detect — as soon as they occur in the earlier stages — any adverse events," said co-chair Dr. Joanne Langley, a pediatric infectious diseases expert and physician based at the Canadian Center for Vaccinology at Dalhousie University.

"Someone could have, for example, a car accident, and that is considered an adverse event following immunization," she told The Current's Matt Galloway.

AstraZeneca announced the temporary halt Tuesday, saying it affected its late-stage studies in the U.S., Britain, Brazil and South Africa. The company did not give specific detail about the illness, but said it was "working to expedite the review of the single event to minimize any potential impact on the trial timeline."

COVID-19 vaccine trial paused over 'unexplained illness'

2 years ago
Duration 3:37
AstraZeneca has paused global trials of its experimental coronavirus vaccine due to an unexplained illness in a study participant. The company is investigating whether the illness is a side-effect from the shot.

Two other companies, Moderna and Pfizer/BioNTech are in large final-phase tests in the United States, with Langley suggesting that "all of the trials could potentially have pauses." 

"It doesn't mean they wouldn't ultimately be safe vaccines," she said. "There could be other very good explanations for each of these adverse events."

The international standard is to first provide immediate care to the participant, and then conduct an investigation into whether there's a link between the vaccine and the event, Langley said.

"It's a very sensitive way to detect anything, so … nothing falls through the sieve and you don't miss any adverse events," she said. 

"We don't want anyone else exposed to the vaccine, in the event that it is related to the vaccine."

Backing for early-stage vaccines criticized

The members of Canada's COVID-19 Vaccine Task Force were revealed by the federal government last month, tasked with advising Canadian leaders on the more than 150 vaccine candidates under development globally.

The federal government has so far made agreements with Pfizer/BioNTech, Moderna Therapeutics, Novavax and Janssen Pharmaceutical Companies, a subsidiary of Johnson & Johnson.

Ottawa secures access to 2 more potential COVID-19 vaccines

2 years ago
Duration 2:07
The federal government has announced deals to buy millions of potential COVID-19 vaccine doses from two American drug companies, on top of its existing deal with two other U.S. firms. The government is aggressively looking for backup plans after its deal with a Chinese company CanSino fell apart recently.

The government has also invested in Canadian researchers exploring vaccine candidates — a move that Amir Attaran, a professor in the Faculty of Law at the School of Epidemiology and Public Health at the University of Ottawa, criticized in a Maclean's column.

"You have several companies in the third and final phase of clinical trials, they're very near the finish line," Attaran told The Current

"But instead of putting money towards those companies and getting them across the finish line, the Vaccine Task Force seems to have recommended that the federal government put money towards upstart, new, inexperienced Canadian companies."

Those companies "aren't at the third phase, or even the second phase, but they're just starting the first phase or hoping to start it in a few months," he said.

Mark Lievonen, Langley's co-chair on the Task Force, said the panel is "trying to find the best vaccine candidate, and some of that effort includes supporting companies in Canada."

"In looking at the data and having discussions amongst us, we've been able to arrive at consensus recommendations as to those that we think look the most promising," said Lievonen, former president of Sanofi Pasteur Ltd., the Canadian vaccine division of the pharmaceutical company, Sanofi.

"It's a broad portfolio, it's risk-balanced, and we provided advice on that basis." 

Infectious disease specialist says don't rush vaccine development

2 years ago
Duration 1:30
A coronavirus vaccine could be in circulation by mid-2021, says infectious disease specialist Dr. Michael Gardam, but he cautions against rushing the testing process.

Conflicts of interest not public

The Task Force has also been criticized for not going public with potential conflicts of interests of its members, after Global News reported that members have recused themselves from discussions 18 times since June over potential conflicts.

"You've got a group of Canadians who are making recommendations on billion-dollar purchases of life-saving vaccines," said Attaran.

"Many of them are linked to the pharmaceutical industry, some of them even take money to the present-day from the pharmaceutical industry," he said.

Langley said Task Force members have all disclosed their relationships with commercial interests and also provinces and territories, and update that disclosure at every meeting.

"For example, my potential conflict would be that we do vaccine research at the Canadian Center for Vaccinology," she said.

Infectious disease specialist explains what may have halted AstraZeneca vaccine trial

2 years ago
Duration 1:23
Dr. Sumon Chakrabarti says a condition called transverse myelitis may have been the adverse reaction that forced AstraZeneca to pause a trial of a coronavirus vaccine.

If her work there involved a vaccine trial with a company now involved in COVID-19 research, the money to fund the trial "would go to Dalhousie University — it doesn't come to me," she said.

"But I have to declare that because it is indeed a relationship with a company, and that's fine."

Lievonen and two other task force members have all worked for Sanofi Pasteur Ltd. or its previous incarnation Connaught Laboratories.

Sanofi is working with GlaxoSmithKline on developing a COVID-19 vaccine, which is in clinical trials, according to the company's website.

Lievonen said "we all recuse ourselves from any discussions and advice regarding anything to do with Sanofi, and the candidate vaccine that they have."

When asked if potential conflicts of interest should be made public, Langley said Task Force members were not paid, and "it's not standard to require volunteers to declare their conflicts of interest publicly," she said. 

"We're doing it because we love Canada and we are compelled to see this as the first priority in our lives right now."

Written by Padraig Moran. Produced by Julie Crysler.

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