The Food and Drug Administration (FDA) on Wednesday said that health officials may be able to obtain as many as seven doses of Pfizer’s coronavirus vaccine from vials initially intended to hold just five.
Hospital pharmacists had noted the discovery on Twitter and pharmacy message boards this week as front-line health care workers began receiving the vaccine on Monday.
On Wednesday evening, the FDA officially released a statement on Twitter, writing that it was aware “that some vials of the Pfizer-BioNTech #COVID19 Vaccine have contained extra product after five doses are obtained.”
“At this time, given the public health emergency, FDA is advising that it is acceptable to use every full dose obtainable (the sixth, or possibly even a seventh) from each vial, pending resolution of the issue,” the FDA continued in a follow-up tweet.
However, the FDA added that remaining material should not be combined from multiple vials to create a full dose and that the agency was “working with Pfizer to determine the best path forward, and will share additional updates as we have them.”
The FDA is aware that some vials of the Pfizer-BioNTech #COVID19 Vaccine have contained extra product after five doses are obtained. The agency is working with Pfizer to determine the best path forward, and will share additional updates as we have them. https://t.co/0jiiyEmug7— U.S. FDA (@US_FDA) December 17, 2020
However, since the vials are preservative free, it is critical to note that any further remaining product that does not constitute a full dose should not be pooled from multiple vials to create one.— U.S. FDA (@US_FDA) December 17, 2020
Politico first reported the extra dosage finding prior to the FDA’s public announcement.
According to the news outlet, a federal health official notified vaccine providers Wednesday morning that they may use every dose able to be obtained from a single vial. Pfizer learned of this change by the afternoon.
Erin Fox, a pharmacy expert at University of Utah who monitors drug shortages, told Politico that pharmaceutical manufacturers tend to overfill vaccine vials in the event of spills and other waste.
“It’s pretty unusual to have a full extra dose or more though — but it does seem to be there!” she said in an email to the news outlet.
Pfizer spokesperson Sharon Castillo told Politico earlier Wednesday that “the amount of vaccine remaining in the multidose vial after removal of 5 doses can vary, depending on the type of needles and syringes used.”
Pfizer has said it has manufactured enough of the vaccine to administer at least 25 million doses to the United States before the end of the year, enough for 12.5 million people, as the vaccine requires two shots within weeks of each other.
Federal officials have already distributed about 2.9 million doses following the FDA’s emergency use approval last week.
Final trial data showed Pfizer’s vaccine to be 95 percent effective at preventing COVID-19.
The vaccine candidate developed by Moderna, which has a similar efficacy rate, is also being considered for FDA emergency use approval this week.