After an independent regulatory review, Health Canada has agreed with a request from Pfizer to recognize that each vial of the company’s vaccine includes six doses, not five.
The labelling change means that more shots can be squeezed out of each vial — and the company can ship fewer vials and still meet its contractual obligations to send a certain number of doses to its customers.
While some provinces, notably Saskatchewan and Quebec, have had some success extracting more from each vial, until now Health Canada had stipulated that only five shots should be extracted.
Health Canada and other international regulators require vials to include a certain amount of overfill to ensure there is sufficient vaccine in each vial to yield the expected doses.
But, in its review, the regulator determined that six full doses can be consistently obtained from vials with the use of low dead-volume syringes, which the government has scrambled to order in recent weeks. The first order of these syringes has already arrived in Canada, with more expected in the weeks ahead.
“In order to extract a sixth dose reliably and consistently, a specialized syringe should be used,” said Dr. Supriya Sharma, Health Canada’s chief medical adviser.
Change follows similar move in U.S. and Europe
Health Canada’s move follows a similar label change by the U.S. Food and Drug Administration (FDA) late last year and the European Medicines Agency.
While the label change comes into effect immediately, shipments to Canada for this week have already begun and are calculated at five doses per vial.
The new designation means fewer vials could be shipped in the weeks ahead, but the number of extractable doses will remain the same, as long as provinces are properly equipped with the syringes. Under its contract, Canada has ordered a certain number of doses from Pfizer — not vials.
“While there is a change in doses contained in each vial, the country’s overall allotment from the manufacturer remains the same,” said Maj.-Gen Dany Fortin, the military commander leading vaccine logistics at the Public Health Agency of Canada.
After weeks of lower shipments because of production delays, Fortin said Pfizer is prepared to significantly ramp up shipments in coming weeks as it looks to meet its promised target of delivering four million doses by the end of March.
“With the change in product monograph, we expect to receive and distribute approximately 400,000 doses next week and 475,000 doses in the last week of February,” Fortin said.
As part of this label change authorization, Pfizer is required to provide continued educational support to vaccine administration sites in Canada and help the government to acquire more of the specialized syringes, if required.