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NCT05501561 · ClinicalTrials.gov registry record · Phase 2
Safety and Immunogenicity of Different Formulations of an MF59-Adjuvanted Influenza Vaccine in Older Adults ≥50 Years of Age
A Phase 2 study, sponsored by Seqirus.
- Completed
- Registry status
- Phase 2
- Development phase
- 1,056
- Enrollment target
NCT05501561: Completed Phase 2 study, sponsored by Seqirus.
NCT05501561 is a Phase 2 study that has completed, run by Seqirus. The registered enrollment target is 1,056 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (694% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05501561, a Phase 2 study, has completed, sponsored by Seqirus.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 1,056 participants
- Enrollment target
Study Summary
This Phase 2, randomized, observer-blind, dose-confirmation clinical study evaluated different formulations of MF59-Adjuvanted Quadrivalent Subunit Inactivated Influenza Vaccine. Approximately 1000 subjects were randomized into 1 of 4 possible treatment groups with approximately 250 participants per group. Every participant received an influenza vaccine injection on Day 1 and were to be followed up for approximately 6 months following injection. The primary immunogenicity analysis is based on Day 29 serology data.
Primary Outcome
GMTs on Day 1 (prior to vaccination) and Day 29 as determined by HI assay against each of the 4 vaccine strains. No hypothesis testing was performed for the primary immunogenicity objectives.
Interventions
- BIOLOGICAL Experimental: IIV-A Investigational IIV-A administered as a single dose intramuscularly on Day 1
- BIOLOGICAL Experimental: aIIV-B Investigational aIIV-B administered as a single dose intramuscularly on Day 1
- BIOLOGICAL Experimental: aIIV-C Investigational aIIV-C administered as a single dose intramuscularly on Day 1
- BIOLOGICAL Active Comparator: Licensed IIV IIV administered as a single dose intramuscularly on Day 1
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 1,056 participants |
| Start Date | 2022-08-25 |
| Est. Completion | 2023-03-31 |
| Phase | Phase 2 |
What the finished NCT05501561 record still lists
NCT05501561 is an interventional study that assigns participants to a tested intervention. Its 1,056 participants enrollment target places it among the larger protocols in the corpus, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (694% higher).
The record links to 0 conditions, and to 4 interventions - of which Experimental: IIV-A Investigational IIV-A administered as a single dose intramuscularly on Day 1 is the first listed.
NCT05501561 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05501561 about?
NCT05501561 is a clinical study titled "Safety and Immunogenicity of Different Formulations of an MF59-Adjuvanted Influenza Vaccine in Older Adults ≥50 Years of Age". This Phase 2, randomized, observer-blind, dose-confirmation clinical study evaluated different formulations of MF59-Adjuvanted Quadrivalent Subunit Inactivated Influenza Vaccine. Approximately 1000 subjects were randomized into 1 of 4 possible treatment groups with approximately 250 participants per...
What is the current status of trial NCT05501561?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 1,056 participants. The study started on 2022-08-25. Estimated completion is 2023-03-31.
What interventions are being tested in trial NCT05501561?
The interventions under investigation include: Experimental: IIV-A Investigational IIV-A administered as a single dose intramuscularly on Day 1 (BIOLOGICAL), Experimental: aIIV-B Investigational aIIV-B administered as a single dose intramuscularly on Day 1 (BIOLOGICAL), Experimental: aIIV-C Investigational aIIV-C administered as a single dose intramuscularly on Day 1 (BIOLOGICAL), Active Comparator: Licensed IIV IIV administered as a single dose intramuscularly on Day 1 (BIOLOGICAL).
Who is sponsoring clinical trial NCT05501561?
This trial is sponsored by Seqirus, which has 25 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05501561's enrollment target sits among peer trials
1,056 24th of 2000 higher than 1,977 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 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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