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NCT06633835 · ClinicalTrials.gov registry record · Phase 4

Impact of Reactogenicity of the 2024-2025 COVID-19 Vaccines on Health Care Workers and First Responders in the United States

A Phase 4 study of COVID-19 and SARS CoV 2 Infection, sponsored by Novavax.

Active
Registry status
Phase 4
Development phase
660
Enrollment target
1
Study location

NCT06633835: Active Phase 4 study of COVID-19 and SARS CoV 2 Infection, sponsored by Novavax.

NCT06633835 is a Phase 4 study of COVID-19 and SARS CoV 2 Infection that is active but no longer recruiting, run by Novavax. The registered enrollment target is 660 participants, below the 38,463-participant average among 298 other COVID-19 trials with a reported enrollment target (98% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT06633835, a Phase 4 study of COVID-19 and SARS CoV 2 Infection, is active but no longer recruiting, sponsored by Novavax.

ACTIVE NOT RECRUITING
Registry status
Phase 4
Development phase
660 participants
Enrollment target
1
Study location

Study Summary

To assess the impact of reactogenicity among health care workers and first responders receiving an updated 2024-25 Novavax COVID-19 vaccine as compared with those receiving an updated 2024-25 Pfizer-BioNTech mRNA COVID-19 vaccine

Primary Outcome

Percentage of participants that experienced any solicited systemic reactogenicity symptoms after receiving a single dose of 2024-25 Novavax COVID-19 vaccine or 2024-25 Pfizer-BioNTech mRNA COVID-19 vaccine during the first two days post vaccination.

Interventions

  • BIOLOGICAL protein subunit: Novavax COVID-19 vaccine
  • BIOLOGICAL Pfizer mRNA COVID-19 vaccine

Study Locations (1)

Utah

  • University of Utah School of Medicine - Salt Lake City

Trial Details

FieldValue
Enrollment Target 660 participants
Start Date 2024-09-20
Est. Completion 2025-08-31
Phase Phase 4
Novavax

31 total trials

What the registry record for NCT06633835 still lists

NCT06633835 is an interventional study that assigns participants to a tested intervention. The registered 660 participants enrollment target is mid-sized for trials with a published cap, below the 38,463-participant average among 298 other COVID-19 trials with a reported enrollment target (98% lower).

The record links to 3 conditions, with COVID-19 appearing as the primary indexed condition, and to 2 interventions - of which protein subunit: Novavax COVID-19 vaccine is the first listed.

NCT06633835 reports a single indexed study location in Utah.

Frequently Asked Questions

What is clinical trial NCT06633835 about?

NCT06633835 is a clinical study titled "Impact of Reactogenicity of the 2024-2025 COVID-19 Vaccines on Health Care Workers and First Responders in the United States". To assess the impact of reactogenicity among health care workers and first responders receiving an updated 2024-25 Novavax COVID-19 vaccine as compared with those receiving an updated 2024-25 Pfizer-BioNTech mRNA COVID-19 vaccine

What is the current status of trial NCT06633835?

This trial is currently active not recruiting. It is a Phase 4 study. The enrollment target is 660 participants. The study started on 2024-09-20. Estimated completion is 2025-08-31.

What conditions does trial NCT06633835 study?

This clinical trial studies the following conditions: COVID-19, SARS CoV 2 Infection, Vaccine-Preventable Diseases.

What interventions are being tested in trial NCT06633835?

The interventions under investigation include: protein subunit: Novavax COVID-19 vaccine (BIOLOGICAL), Pfizer mRNA COVID-19 vaccine (BIOLOGICAL).

Who is sponsoring clinical trial NCT06633835?

This trial is sponsored by Novavax, which has 31 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT06633835 being conducted?

This trial has 1 study location across Utah. 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 NCT06633835's enrollment target sits among peer trials

660 96th of 298 higher than 202 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 NCT06633835, the US trial registry maintained by the National Library of Medicine. NCT06633835 (mid enrollment · single site footprint · active not recruiting) retrieved and formatted by PlainTrial, see methodology.