(REUTERS) – Canadian health officials said on Monday they would stop offering AstraZeneca’s COVID-19 vaccine to people under the age of 55. They also said there’s a need for a new analysis of the shot’s benefits and risks based on age and gender.
The decision comes after reports from Europe of rare, but serious, blood clots, bleeding, and in some cases death after vaccination, mainly in young women. No such cases have been reported in Canada, with about 307,000 AstraZeneca doses administered thus far.
“We are pausing the use of AstraZeneca vaccine to adults under 55 years of age pending further risk-benefit analysis,” said Deputy Chief Public Health Officer Howard Njoo at a media briefing.
Njoo later noted that Canada was taking this “prudent” approach because alternative vaccines are available. Most of Canada’s vaccines so far have come from Pfizer Inc and Moderna Inc.
The National Advisory Council of Immunization (NACI), an independent expert panel, said the rate at which the clotting complication happens is not yet clear. So far, 40 per cent of people who have developed it have died, but that may fall as more cases are identified and treated early, it said.
Older people face a greater risk of hospitalization and death from COVID-19, and the complication seems to be more rare in that age group, NACI said, so they can be offered the vaccine “with informed consent.”
Health Canada said in a statement it would add new terms and conditions to the vaccine’s authorizations, including “a requirement that the manufacturers conduct a detailed assessment of the benefits and risks of the vaccine by age and sex in the Canadian context.”
Once it has the information it has requested, Health Canada “will determine if additional regulatory actions are necessary,” but it was not immediately clear how long the assessment might take.
The pause affects two versions of the vaccine approved in Canada, one granted to AstraZeneca Canada, and a second for the Serum Institute of India (SII) – which is manufacturing its own version of the vaccine under license – and its Canadian partner Verity Pharmaceuticals.
Many countries in Europe briefly paused the use of the AstraZeneca vaccine earlier this month while investigating the blood clot incidents. Canada made the decision to continue to administer it, saying that the benefits of vaccination outweighed potential risks.
Canada is expecting another 1.5 million doses of the AstraZeneca vaccine this week from the United States, which is yet to authorize its use. Canada has ordered more than 20 million doses from AstraZeneca and SII.