TORONTO -- The clock is ticking on nearly 50,000 shelved doses of AstraZeneca, set to expire as soon as the end of this month, but Ontario officials say there is no plan for their potential use as second doses just yet.

“That determination has not yet been made,” Ontario Health Minister Christine Elliott said Thursday.

Elliott had vowed in the legislature Wednesday that “nothing will be wasted,” but Ontario’s Chief Medical Officer Dr. David Williams said Thursday that his team was still reviewing the latest data on the viral-vector vaccine.

The province pressed pause on use of AstraZeneca on May 11, following a slight increase in rare reports of associated blood clots. Ontario will no longer use the vaccine for first shots, but is deliberating resuming use for second doses.

Ontario officials have pegged the risk of clots from an AstraZeneca booster shot at about one in a million.

“Data from the U.K. indicates that any problems with the second shot are far less than any problems with the first shot,” Elliott said.

Despite the province’s reluctance to publicly confirm plans for the expiring AstraZeneca, the Ontario Pharmacists Association told CTV Toronto Thursday that it expects that its pharmacies will be able to offer the vaccine as a second dose—potentially well ahead of the planned four-month dosing interval, in order to meet the best-before dates.

Informed consent would be required under this scenario, said a spokesperson.

Infectious Disease Expert Dr. Isaac Bogoch said Thursday he expects that Ontarians who received AstraZeneca as a first dose will also have the option to receive a Pfizer shot as a booster.

“People will very likely have a decision,” Bogoch said. “They can make the decision on their own, and quite frankly, either decision is going to be just fine.”

Preliminary results released this week from a Spanish study indicated that giving a second dose of Pfizer to people who received a first shot of AstraZeneca was both safe and effective.