Canada’s National Advisory Committee on Immunization (NACI) says it does not recommend the newly approved AstraZeneca vaccine for those 65 years of age and older.
Upon approval on Friday, Health Canada stated that the clinical trial data was limited for people over the age of 65, but that blood tests showed seniors did produce COVID-19 antibodies from the vaccine. Also “real world evidence and post-market experience” in places the vaccine is already in use show “a potential benefit and no safety concerns” with giving the vaccine to seniors.
However an update on the government’s website on Monday says “NACI does not recommend the use of [the AstraZeneca] 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.”
In clinical trials, the AstraZeneca shot, which is a non-replicating viral vector vaccine, has proven to be 62 per cent effective in those between the ages of 18 and 64. The Pfizer and Moderna shots, which are mRNA vaccines, have a higher efficacy of approximately 94 per cent.
The update also included potential allergens in the AstraZeneca vaccine and listed a single ingredient — polysorbate 80. While case reports of anaphylaxis to polysorbate 80 have been noted, the ingredient is found in other medical preparations like vitamin oils, tablets and anti-cancers agents as well as some cosmetics.
Side-effects listed for AstraZeneca include pain at the site of the injection and redness after both doses.
AstraZeneca is the most flexible of the vaccines now approved in Canada, able to be shipped and stored in refrigerators, rather than freezers. Open vials can be saved for up to 48 hours in a refrigerator as long as they haven’t been out of the fridge for more than six hours total before being used.
Both Pfizer and Moderna are shipped frozen, with the former requiring ultracold storage in special freezers, and both must be used entirely after a vial is opened.
Canada is to get 20 million doses of the AstraZeneca vaccine – which is administered in two doses – between April and September. Those doses are manufactured in the United States.
Another 1.9 million doses are expected before the end of June through the international vaccine sharing program known as COVAX, with the first 500,000 of those potentially arriving before the end of March.
Canada has been criticized for taking doses from COVAX, when it has so many doses coming from private deals with vaccine makers.