Pfizer COVID-19 Vaccine Vials May Contain More Doses than Previously Thought

December 17, 2020
Kevin Kunzmann

Up to 40% more doses—or, enough to vaccinate another person with two doses—has been observed in the vials distributed at the beginning of this week.

The early distribution of the first coronavirus 2019 (COVID-19) vaccine in the US—previously anticipated to be a logistical challenge given the particularities of the vaccine’s storage needs—has actually resulted in a pleasant surprise.

Pharmacists administering the first doses of two-dose mRNA vaccine BNT162b2, from Pfizer and BioNTech, have observed the advised five-dose vials distributed in lots to designated administration sites could actually hold a sixth or even seventh dose in each supply.

Now, the US Food and Drug Administration (FDA) has walked back its labeling information from the Emergency Use Authorization (EUA) granted to the vaccine last week, permitting pharmacists to use the additional doses.

Experts informed Politico in its initial report of the additional doses that it’s fairly common for manufacturers to overfill vaccine vials in response to spill and waste risks. That said, a 40% increase in vial doses is a rarity.

A Pfizer spokesperson said the amount of vaccine available after 5 doses are used can vary based on needles and syringes used. They advised vaccinators consult their own institution’s policies on use.

Officials, however, did advise that excess vaccine should never be pooled with that left over from other vials.

At the time of the FDA’s authorization of BNT162b2 last week, Pfizer projected to produce about 50 million doses globally by the end of this year, then another 1.3 billion doses by the end of 2021. They also are nearing an agreement with the US Department of Health and Human Services (DHHS) to meet the US Operation Warp Speed program goal of 300 million COVID-19 vaccine doses by next year.

Through the agreement, the federal government would receive 100 million BNT162b2 doses upon EUA approval, for a cost of $1.95 billion and an option to acquire another 500 million doses.

Very suddenly, Pfizer’s vaccine contribution in 2021 may vary anywhere from 1.3 billion to nearly 2 billion—which, as a two-dose vaccine, would provide protection to 1 billion people.