Confusion in labeling resulted in wasted doses of Pfizer Covid-19 vaccine

W.Because the Covid-19 vaccine was scarce, hospital pharmacists were in the unexpected position to throw out one in six doses of the first Pfizer-BioNTech vaccines distributed in the United States this week.

The confusion came over the labeling: the vaccine comes in vials labeled enough for five doses. But pharmacists found that, after thawing and mixing the contents with a diluent, each vial contained enough vaccine for six doses. The last dose had to be discarded without the explicit consent of the manufacturer.

“It was clear early on that there was some extra volume,” said Russell Findlay, pharmacy manager at University of Utah Health. His colleagues called Pfizer Tuesday to ask if they could use the extra dose, Findlay said, but the company declined to provide a definitive answer.


Pharmacists and executives at various health care systems said they did not feel they could risk using the extra dose, especially since Pfizer’s vaccine requires two doses, 21 days apart, to be effective. “We are not entirely sure of our future supply. Let’s say we’re on the six, but we’re getting fewer doses in the future, maybe we don’t have enough for the second dose, ”said Findlay. “We have to be very careful when managing that stock.”

Across the country in Boston, Paul Biddinger, medical director for emergency preparedness at Mass General Brigham, said he had heard of the extra doses from the introduction of the British vaccine earlier this month. Despite being prepared, his team still had to throw out the extra doses on the first day of distribution.


In Texas, the extra doses were discarded on the first day of distribution, but Wednesday morning Roberta Schwartz, CEO of Houston Methodist Hospital, said her team had heard from Pfizer that it was okay to use the contents of the vial.

Finally, Wednesday afternoon, the U.S. Food and Drug Administration updated its guidelines and says health care providers should feel free to use all full doses in each vial. At this point, given the public health emergency, the FDA recommends that it is acceptable to use any full dose available (the sixth or possibly even a seventh) from each vial, pending a solution of the problem, ”spokesman Abigail Capobianco wrote in an email to STAT. But any additional half doses should not be combined with half doses from other vials to make a whole, she added.

But Pfizer was less definitive. Each vial contains enough vaccine for at least five doses, spokesman Sharon Castillo said in an email to STAT, and each dose should contain 0.3 ml. “The amount of vaccine remaining in the multi-dose vial after 5-dose disposal can vary, depending on the type of needles and syringes used,” she wrote. At the moment we cannot recommend the use of the remaining amount of vaccine from each vial. Vaccinators should consult their facility’s policies for the use of multiple dose vials. “

If the UK dosage confusion had arisen, ideally the FDA and Pfizer should have provided clearer instructions on how to use the additional dose before distribution began in the US this week, said John Grabenstein, adviser to the American Pharmacists Association. “In a situation with a limited supply, any waste is a pity.”

But all injectable drugs are in excess, he said, and the early stages of clinical practice normally raise minor issues. ‘In the first week, a thousand things have to be tackled. It could only now rise to the check-out level, ”he said.

It makes sense to have some leftover liquid in a bottle, Findlay said. Small variations in the syringes used by different health systems can have minor effects on the size of each dose, and changes in air pressure at different altitudes can also affect the volume of the vaccine in a vial.

Despite the dose confusion, the first day of vaccine administration was a success, he said, “Yesterday was the best workday I’ve ever had.”