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NCT04761822 · ClinicalTrials.gov registry record · Phase 2

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

A Phase 2 study of COVID-19 and SARS-CoV Infection, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).

Completed
Registry status
Phase 2
Development phase
746
Enrollment target
20
Study locations

NCT04761822: Completed Phase 2 study of COVID-19 and SARS-CoV Infection, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).

NCT04761822 is a Phase 2 study of COVID-19 and SARS-CoV Infection that has completed, run by National Institute of Allergy and Infectious Diseases (NIAID). The registered enrollment target is 746 participants, below the 38,462-participant average among 298 other COVID-19 trials with a reported enrollment target (98% lower). The trial reports 20 study locations across 13 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04761822, a Phase 2 study of COVID-19 and SARS-CoV Infection, has completed, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).

COMPLETED
Registry status
Phase 2
Development phase
746 participants
Enrollment target
20
Study locations

Study Summary

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

Primary Outcome

Allergic reactions were graded using the Consortium of Food Allergy Research (CoFAR) Grading Scale for Systemic Allergic Reactions, Version 3.0. The scale ranges from grade 1 through 5. The higher the grade, the more severe the allergic reaction. Tryptase is an enzyme released into the blood during an allergic reaction. An elevation in tryptase is defined as a value that is higher than 1.2 x the baseline tryptase plus 2 ng/ml. Subjects who did not receive their second dose of the vaccine were no

Interventions

  • BIOLOGICAL Placebo
  • BIOLOGICAL Moderna COVID-19 Vaccine
  • BIOLOGICAL Pfizer-BioNTech COVID-19 Vaccine

Study Locations (20)

New York

  • Mount Sinai Hospital, Department of Medicine, Division of Clinical Immunology - New York
  • Columbia University Irving Medical Center - New York
  • Rochester Regional Health - Rochester

California

  • University of California, Los Angeles Medical Center - Los Angeles
  • Stanford Medicine, Sean N. Parker Center for Allergy & Asthma Research - Stanford

Florida

  • University Health, University of Miami Health System - Miami
  • University of South Florida Asthma Allergy and Immunology Clinical Research Unit - Tampa

Illinois

  • Sinus and Allergy Center of Northwestern University - Chicago
  • NorthShore University HealthSystem, Dermatology Clinical Trials Unit - Skokie

Massachusetts

  • Massachusetts General Hospital - Boston
  • Brigham and Women's Hospital - Boston

Michigan

  • University of Michigan Health - Ann Arbor
  • Henry Ford Hospital and Health System - Detroit

Arizona

  • University of Arizona Health Sciences, College of Medicine Tucson, Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine - Tucson

Arkansas

  • Arkansas Children's, University of Arkansas for Medical Sciences - Little Rock

Trial Details

FieldValue
Enrollment Target 746 participants
Start Date 2021-04-07
Est. Completion 2022-04-27
Phase Phase 2

What the finished NCT04761822 record still lists

NCT04761822 is an interventional study that assigns participants to a tested intervention. The registered 746 participants enrollment target is mid-sized for trials with a published cap, below the 38,462-participant average among 298 other COVID-19 trials with a reported enrollment target (98% lower).

The record links to 4 conditions, with COVID-19 appearing as the primary indexed condition, and to 3 interventions - of which Placebo is the first listed.

NCT04761822 names 20 study sites across 13 states, led by New York, California, Florida.

Frequently Asked Questions

What is clinical trial NCT04761822 about?

NCT04761822 is a clinical study titled "COVID19 SARS Vaccinations: Systemic Allergic Reactions to SARS-CoV-2 Vaccinations". 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 eith...

What is the current status of trial NCT04761822?

This trial is currently completed. It is a Phase 2 study. The enrollment target is 746 participants. The study started on 2021-04-07. Estimated completion is 2022-04-27.

What conditions does trial NCT04761822 study?

This clinical trial studies the following conditions: COVID-19, SARS-CoV Infection, Allergic Reaction, Mast Cell Disorder.

What interventions are being tested in trial NCT04761822?

The interventions under investigation include: Placebo (BIOLOGICAL), Moderna COVID-19 Vaccine (BIOLOGICAL), Pfizer-BioNTech COVID-19 Vaccine (BIOLOGICAL).

Who is sponsoring clinical trial NCT04761822?

This trial is sponsored by National Institute of Allergy and Infectious Diseases (NIAID), which has 2,006 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT04761822 being conducted?

This trial has 20 study locations across Arizona, Arkansas, California, Colorado, Florida. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for COVID-19

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT04761822's enrollment target sits among peer trials

746 93rd of 298 higher than 206 of 298 other COVID-19 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other COVID-19 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT04761822, the US trial registry maintained by the National Library of Medicine. NCT04761822 (mid enrollment · wide site footprint · completed) retrieved and formatted by PlainTrial, see methodology.