Newly approved vaccine not advised for seniors,
‘Limited’ data on seniors in clinical trials leads to health panel’s caution
Canada has become the latest country to err on the side of caution when using the newly authorized AstraZeneca COVID-19 vaccine, with national recommendations that advise health authorities against giving it to those over 65.
The development came the same day that France reversed course on similar advice, as the question of whether or not enough is known about the dose’s effectiveness in seniors continued to divide experts.
In updated guidelines released Monday, Canada’s National Advisory Committee on Immunization said it “does not recommend the use of this vaccine in individuals 65 years of age and older due to limited information on the efficacy of this vaccine in this age group at this time.”
On Friday, Health Canada had OK’d the dose for anyone 18 and over. Health Canada did acknowledge there was “limited information” from seniors in clinical trials. However, it said there is “emerging real world evidence” from countries where the vaccine is being used that suggests “a potential benefit and no safety concerns.”
While Health Canada makes the decision on whether a vaccine can be used in this country, the advisory committee gives non-binding advice as to how a vaccine should be used.
Dr. Lynora Saxinger, an infectious diseases specialist at the University of Alberta, stresses the committee’s advice doesn’t mean the shot is unsafe or not effective in older adults, just that more data is needed.
“There’s this scary tendency for people to take that to mean that it doesn’t work in that group. And no, it just means that there’s not that many people over the age of 65 in the AstraZeneca trials overall. So the data pool is much, much smaller.”
It’s not unreasonable that the two bodies came to different conclusions, she said, as Health Canada looks at the overall data to decide whether a product can be authorized, while NaCI is continually updating recommendations based on new information.
The vaccine, which was made in partnership with Oxford University, is in use in dozens of jurisdictions globally. But the lack of data about its effectiveness for older adults has divided countries around the world.
Older adults have been particularly hard hit by the pandemic and generally have weaker immune systems, so most vaccine trials were designed to include seniors to determine whether shots were effective in all age groups.
AstraZeneca has faced criticism that it did not collect enough data to make sure it worked on older adults.
When it was authorized in Europe in January, the regulator there flagged the lack of data in seniors but said protection was still expected. A slew of European countries, including France, Germany and the Netherlands initially only recommended it for those under 65. Switzerland, meanwhile, ruled out approving it at all.
Observers have argued that not giving the dose to seniors has slowed down vaccination efforts in some countries and, given the relative ease with which the shot can be transported, made getting other shots to vulnerable seniors harder.
Another cluster of countries, most notably, the United Kingdom, are using it for all ages — and defending the approach.
“The data we have show that the vaccine produces a strong immune response in the over-65s, and that it is safe,” Dr. June Raine, the chief executive of the British regulator told the BBC earlier this month.
Part of the challenge facing regulators is that while early decisions were based on large scale trial data, officials now have access to new information pouring in from actual vaccination efforts around the world.
At least one country has changed its stance as a result, with the French health minister announcing Monday that new data supported giving the dose to all ages.
According to the Financial Times, French Health Minister Olivier Véran said in a TV interview that a panel of experts advising his government had recommended they reverse course on a month-old policy, arguing that new evidence supported giving the shot to seniors after all.
While NaCI provides national advice on immunization in this country, it’s up to the provinces to make their own final decisions.
If they do decide to adopt these recommendations, it will likely mean the mRNA vaccines made by Pfizer and Moderna — the other two vaccines authorized for use in Canada — are prioritized for older adults, Saxinger said.