Allergic Reactions to COVID-19 Vaccines

The National Institute of Allergy and Infectious Diseases is conducting a vaccine allergy study to determine whether people who are highly allergic or have a mast cell disorder are at increased risk for an immediate, systemic allergic reaction to the Moderna or Pfizer-BioNtech COVID-19 vaccines. A systemic allergic reaction is one that occurs in one or more parts of the body beyond the site of the injection. “If such an allergic reaction occurs in study participants, investigators will assess whether the reactions are more frequent in participants who are highly allergic or have a mast cell disorder than in participants with no allergic history.”(1)

The National Institute of Health advises that, for most people, the benefits of COVID-19 vaccination far outweigh the risks. The results of this trial will be used to help doctors advise people who are highly allergic or have a mast cell disorder about the risks and benefits of receiving the vaccine.(1)

Participants will be divided in groups. “Participants in each group will be assigned at random to receive either the Pfizer-BioNTech vaccine (one third of the group); the Moderna vaccine (one third); a placebo followed by the Pfizer-BioNTech vaccine (one sixth); or a placebo followed by the Moderna vaccine (one sixth).” Ultimately, all participants will receive a full-dose course of one of the vaccines. Patients’ safety will be carefully monitored throughout the trial.(1)

To learn more about this clinical trial, find out the study sites, and read eligibility requirements, visit https://clinicaltrials.gov/

(1) National Institute of Health, NIH Begins Study of Allergic Reactions to Moderna, Pfizer-BioNTech COVID-19 Vaccines, https://www.nih.gov/news-events/