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NCT05540522 · ClinicalTrials.gov registry record · Phase 3
A Study to Evaluate a Modified RNA Vaccine Against Influenza in Adults 18 Years of Age or Older
A Phase 3 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 3
- Development phase
- 45,789
- Enrollment target
NCT05540522: Completed Phase 3 study, sponsored by Pfizer.
NCT05540522 is a Phase 3 study that has completed, run by Pfizer. The registered enrollment target is 45,789 participants, above the 769-participant average among 15,282 other Phase 3 trials with a reported enrollment target (5854% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05540522, a Phase 3 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 45,789 participants
- Enrollment target
Study Summary
This is a Phase 3, randomized, observer-blinded study to evaluate the efficacy, safety, tolerability, and immunogenicity of a single dose of a quadrivalent influenza modRNA vaccine compared to licensed inactivated influenza vaccine in healthy adults 18 years of age and older.
Primary Outcome
LCI was defined as influenza infection confirmed through through reverse transcription- polymerase chain reaction (RT-PCR) or culture at the central laboratory, unless otherwise specified. Per-protocol ILI was defined as occurrence (new onset or worsening of preexisting condition) of at least 1 respiratory symptoms concurrently with at least 1 systemic symptoms. Data was obtained during the 2022-2023 northern hemisphere influenza season up to surveillance cut-off decided by Sponsor.
Interventions
- BIOLOGICAL Quadrivalent influenza modRNA vaccine
- BIOLOGICAL Quadrivalent influenza vaccine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 45,789 participants |
| Start Date | 2022-09-12 |
| Est. Completion | 2024-03-12 |
| Phase | Phase 3 |
What the finished NCT05540522 record still lists
NCT05540522 is an interventional study that assigns participants to a tested intervention. Its 45,789 participants enrollment target places it among the larger protocols in the corpus, above the 769-participant average among 15,282 other Phase 3 trials with a reported enrollment target (5854% higher).
The record links to 0 conditions, and to 2 interventions - of which Quadrivalent influenza modRNA vaccine is the first listed.
NCT05540522 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05540522 about?
NCT05540522 is a clinical study titled "A Study to Evaluate a Modified RNA Vaccine Against Influenza in Adults 18 Years of Age or Older". This is a Phase 3, randomized, observer-blinded study to evaluate the efficacy, safety, tolerability, and immunogenicity of a single dose of a quadrivalent influenza modRNA vaccine compared to licensed inactivated influenza vaccine in healthy adults 18 years of age and older.
What is the current status of trial NCT05540522?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 45,789 participants. The study started on 2022-09-12. Estimated completion is 2024-03-12.
What interventions are being tested in trial NCT05540522?
The interventions under investigation include: Quadrivalent influenza modRNA vaccine (BIOLOGICAL), Quadrivalent influenza vaccine (BIOLOGICAL).
Who is sponsoring clinical trial NCT05540522?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05540522's enrollment target sits among peer trials
45,789 3rd of 2000 higher than 1,998 of 2,000 other Phase 3 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 3 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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