Prolonged Anaphylaxis to Pfizer Coronavirus Disease 2019 Vaccine: A Case Report and Mechanism of Action.

Background: In response to the devastating effects of the coronavirus disease 2019 pandemic, several vaccine prototypes have been developed, with the Pfizer/BioNTech (BNT162b2) platform being the first to receive emergency use authorization. Although taken to market on an unprecedented timeline, the safety profile of the drug during clinical trials was shown to be favorable. Shortly after release, reports from the Centers for Disease Control and Prevention demonstrated a higher-than-average rate of anaphylaxis to the vaccine that has been the cause for concern for safety officials and the general public alike.