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Is Pfizer Recommending a Switch to a Single-Dose Policy?
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Is Pfizer Recommending a Switch to a Single-Dose Policy?

The vaccine has demonstrated a high efficacy rate after one dose, but the company itself has not suggested any policy changes.

In a letter to the New England Journal of Medicine on February 17, two Canadian researchers, Danuta Skowronski and Gaston De Serres, suggested “deferring second doses” of the COVID-19 vaccine “until all priority group members are offered at least one dose.” The suggestion is based on an analysis of documents from Pfizer that were submitted to the FDA, which found, among other things, that one single dose of the Pfizer vaccine is 92.6 percent effective against COVID-19.

Based on this research, a widely circulated tweet claims “Pfizer says new data shows 1 dose is 93% effective after 2 weeks, almost as good as 2 doses. They urge a change in policy to single dosing.”

Despite this new research, Pfizer hasn’t changed its policy on dosage and is not urging “a change in policy to single dosing.” 

While it’s true that Pfizer data did show an efficacy rate of almost 93 percent after two weeks with just a single dose, it wasn’t the drug company specifically that is recommending a change in policy, but the researchers. 

The author of the tweet was quick to tweet a correction: “CLARIFICATION: The 1st Pfizer related letter (single dose effectiveness) is not directly from Pfizer, but based on Pfizer data.”

The clarification, while accurate, still seems to have left some confusion, and many sharing the original tweet suggesting that Pfizer has changed its policy.  

The Dispatch Fact Check reached out to a spokesperson from Pfizer via email to further clarify the matter: “Right now, we do not have any Pfizer-led data suggesting a change to dosing (see our label) and our current research is specific to two doses 21-days apart.”

Representatives from Pfizer also issued a response to the New England Journal of Medicine letter saying that: “In response to Skowronski and De Serres: we would like to emphasize that alternative dosing regimens of BNT162b2 have not been evaluated. The decision to implement alternative dosing regimens resides with health authorities; however, we at Pfizer believe that it is critical for health authorities to conduct surveillance on implemented alternative dosing schedules to ensure that vaccines provide the maximum possible protection.”

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Khaya Himmelman is a fact checker for The Dispatch. She is a graduate of Columbia Journalism School and Barnard College.