Clinical trialNCT04761822CompletedPhase 2Interventional

COVID19 SARS Vaccinations: Systemic Allergic Reactions to SARS-CoV-2 Vaccinations

SponsorNational Institute of Allergy and Infectious Diseases (NIAID)Enrollment746Allergic ReactionCOVID-19Mast Cell DisorderSARS-CoV Infection

View the registry record on ClinicalTrials.gov

Summary

The lay summary the sponsor registered on ClinicalTrials.gov.

Background: Allergic reactions have been reported to occur after vaccination with both the Pfizer-BioNTech COVID-19 Vaccine and Moderna COVID-19 Vaccine. Allergic reactions range from mild to severe and include life- threatening anaphylactic reactions, although no deaths have been reported with either vaccine. This study is designed with two principal aims: * To estimate the proportions of systemic allergic reactions to the Pfizer-BioNTech COVID-19 Vaccine and the Moderna COVID-19 Vaccine in a High-Allergy/Mast Cell Disorder (HA/MCD) population, and * If the risk in the HA/MCD is demonstrable, to determine whether the proportions are higher in the HA/MCD in comparison to a representative population without severe allergies or mast cell disorders

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Investigators

The overall officials registered on this study. Names that resolve to a findmyKOL profile link to it; the rest are shown as registered.

James R. Baker Jr., MD
Mary H. Weiser Food Allergy Center and Michigan Nanotechnology Institute for Medicine and the Biological Sciences
Study Chair
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N. Franklin Atkinson Jr., MD
Graduate Training Program in Clinical Investigation Associate TP Director, Allergy-Immunology Johns Hopkins Asthma & Allergy Center
Study Chair
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Rebecca S. Gruchalla, MD, PhD
Division of Allergy and Immunology Departments of Internal Medicine and Pediatrics, University of Texas Southwestern
Study Chair
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A profile link is shown only when the registered name resolves to a person record with a confident, namesake-checked match; ambiguous names stay unlinked.

Sites

29 registered facilities, with the per-site recruitment status where the registry publishes one. ClinicalTrials.gov does not publish per-site enrollment counts.

United States

University of Arizona Health Sciences, College of Medicine Tucson, Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine
Tucson, Arizona, United States
Arkansas Children'S, University of Arkansas for Medical Sciences
Little Rock, Arkansas, United States
University of California, Los Angeles Medical Center
Los Angeles, California, United States
Stanford Medicine, Sean N. Parker Center for Allergy & Asthma Research
Stanford, California, United States
National Jewish Health
Denver, Colorado, United States
University Health, University of Miami Health System
Miami, Florida, United States
University of South Florida Asthma Allergy and Immunology Clinical Research Unit
Tampa, Florida, United States
Emory University School of Medicine, Emory Healthcare: Emory Clinic Allergy and Immunology
Atlanta, Georgia, United States
Sinus and Allergy Center of Northwestern University
Chicago, Illinois, United States
Northshore University Healthsystem, Dermatology Clinical Trials Unit
Skokie, Illinois, United States
University of Iowa Health Care
Iowa City, Iowa, United States
Johns Hopkins Bayview Medical Center
Baltimore, Maryland, United States
Brigham and Women'S Hospital
Boston, Massachusetts, United States
Massachusetts General Hospital
Boston, Massachusetts, United States
University of Michigan Health
Ann Arbor, Michigan, United States
Henry Ford Hospital and Health System
Detroit, Michigan, United States
Saint Louis University Care Center for Specialized Medicine
St Louis, Missouri, United States
Columbia University Irving Medical Center
New York, New York, United States
Mount Sinai Hospital, Department of Medicine, Division of Clinical Immunology
New York, New York, United States
Rochester Regional Health
Rochester, New York, United States
North Carolina Translational and Clinical Sciences Institute-Clinical & Translational Research Center (ctrc) at the University of North Carolina at Chapel Hill
Chapel Hill, North Carolina, United States
Cleveland Clinic, Allergy & Clinical Immunology
Cleveland, Ohio, United States
Penn State Health Allergy, Milton S. Hershey Medical Center
Hershey, Pennsylvania, United States
Vanderbilt University Medical Center
Nashville, Tennessee, United States
University of Texas Southwestern Medical Center
Dallas, Texas, United States
Baylor College of Medicine Medical Center
Houston, Texas, United States
University of Virginia Health System: Department of Medicine, Division of Allergy and Immunology
Charlottesville, Virginia, United States
Virginia Commonwealth University, Department of Internal Medicine, Division of Rheumatology, Allergy & Immunology
Richmond, Virginia, United States
University of Wisconsin Asthma Allergy Pulmonary Research
Madison, Wisconsin, United States

Site investigator names are published by ClinicalTrials.gov only while a study recruits, so completed studies list sites without them.

Drugs studied

The drug and biological interventions registered on this study, normalized to their RxNorm ingredient where possible.

Moderna Covid-19 Vaccine →SARS-CoV-2 (COVID-19) vaccine, mRNA spike protein →Placebo

Linked drugs open the directory filtered to KOLs working with them.clinicaltrials.gov ↗

Registration & key dates

Registry attributes as recorded on the ClinicalTrials.gov study record.

Start: 7 Apr 2021
Primary completion: 20 Apr 2022
Completion: 27 Apr 2022
Last update posted: 12 Aug 2025
Registered enrollment: 746
Registry id: NCT04761822

clinicaltrials.gov ↗

Source: ClinicalTrials.gov, via the CTTI AACT database, data as of 24 Aug 2026. Registry facts are shown as registered by the study sponsor; findmyKOL does not interpret them.