Extra Doses Found in Pfizer COVID-19 Vaccine Vials, Expanding Supply

Aislinn Antrim, Assistant Editor

Pfizer’s COVID-19 vaccine vials are supposed to hold 5 doses, but using a sixth or seventh dose could expand the supply by up to 40%.

The FDA said Wednesday that vaccine administrators can use the 1 or 2 extra doses found in many of Pfizer’s coronavirus disease 2019 (COVID-19) vaccine vials, expanding the supply across the country.1

The vials are supposed to hold 5 doses but using a sixth or seventh dose could expand the supply by up to 40%, according to reporting by Politico.1 Confusion about the extra doses had caused some pharmacists to discard the leftover vaccine based on rules set by the FDA last week, but a statement late Wednesday night said pharmacists can use every dose available.1

“Given the public health emergency, FDA is advising that it is acceptable to use every full dose obtainable,” said an agency spokesperson in an interview with Politico.1

The emergency use authorization (EUA) allowed for only 5 doses per vial, according to a tweet from Andy Slavitt, former acting chief of the Centers for Medicare and Medicaid Services during the Obama administration.3 According to Politico, Slavitt said Pfizer is submitting paperwork to allow pharmacists to use the extra doses if they are available.1

According to FDA officials, the remaining doses can vary depending on the types of needles and syringes used. Because of the contamination risk, however, pharmacists should not mix remaining vaccine from multiple vials.1

The EUA for the vaccine was granted on December 12 based on phase 3 trial data demonstrating a vaccine efficacy rate of 95% in participants both with and without a prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The observed efficacy rate in adults aged 65 years and older was more than 94%, with consistency across age, gender, race, and ethnicity demographics.2

During the trial, the vaccine was found to be well tolerated, with no serious safety concerns reported to date by the Data Monitoring Committee. The FDA said the data indicate that the known and potential benefits of the vaccine outweigh the known and potential risks.2

The first batch of 2.9 million doses is continuing to roll out across the United States, with shipments heading to 66 new distribution hubs, according to Reuters. Another 2 million doses could be allocated within the next week along with 5.9 million doses from the Moderna vaccine candidate, which is being reviewed today by an FDA advisory committee.4

The Moderna vaccine candidate was deemed highly effective by the FDA in filing released Tuesday, with a 94.5% efficacy in preventing COVID-19, according to preliminary results from an ongoing phase 3 trial. Data released by the FDA also suggest that the vaccine candidate may prevent the spread of COVID-19, with asymptomatic infection reduced by 63% following administration of the first dose.5

REFERENCES

  • Owermohle S. FDA says Pfizer vaccine vials hold extra doses, expanding supply. Politico; December 16, 2020. https://www.politico.com/news/2020/12/16/pfizer-vaccine-extra-doses-447117. Accessed December 17, 2020.
  • FDA Grants Historic Emergency Use Authorization to COVID-19 Vaccine From Pfizer and BioNTech; Pharmacy Times. December 12, 2020. https://www.pharmacytimes.com/news/fda-grants-historic-emergency-use-authorization-to-covid-19-vaccine-from-pfizer-and-biontech. Accessed December 17, 2020.
  • Tweet from Andy Slavitt, @ASlavitt. Twitter; December 15, 2020. https://twitter.com/ASlavitt/status/1338909906754183168. Accessed December 17, 2020.
  • FDA says extra doses from vials of Pfizer’s COVID-19 vaccine can be used. Reuters; December 16, 2020. https://www.reuters.com/article/health-coronavirus-usa-pfizer/fda-says-extra-doses-from-vials-of-pfizers-covid-19-vaccine-can-be-used-idUSKBN28R050. Accessed December 17, 2020.
  • Moderna COVID-19 Vaccine Shows High Efficacy, Clearing Path for EUA; Pharmacy Times. https://www.pharmacytimes.com/news/moderna-covid-19-vaccine-shows-high-efficacy-clearing-path-for-eua. Accessed December 17, 2020.