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NCT00782431 · ClinicalTrials.gov registry record · Phase 3
Immunogenicity and Safety Study of an Inactivated Influenza Vaccine (Split Virus, Vero Cell Derived) in Adults Aged 50 Years and Older
A Phase 3 study, sponsored by Alachua Government Services.
- Completed
- Registry status
- Phase 3
- Development phase
- 3,208
- Enrollment target
NCT00782431: Completed Phase 3 study, sponsored by Alachua Government Services.
NCT00782431 is a Phase 3 study that has completed, run by Alachua Government Services. The registered enrollment target is 3,208 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (316% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00782431, a Phase 3 study, has completed, sponsored by Alachua Government Services.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 3,208 participants
- Enrollment target
Study Summary
The purpose of this study is to demonstrate the effectiveness (seroprotection and seroconversion as measured by the hemagglutination inhibition \[HI\] assay) of an investigational Vero cell-derived, trivalent, seasonal influenza vaccine in adults 50 years of age and older. Subjects will be randomized in a double-blind fashion to receive a single intramuscular injection of either the investigational vaccine or a licensed egg-derived seasonal influenza vaccine. Blood will be drawn from all subjects for a determination of HI antibody titers on Days 0 and 21, body temperature and injection site reactions will be monitored daily for 7 days. In addition, subjects will be monitored for adverse events and rises in body temperature until Day 21 and again until Day 180.
Primary Outcome
The rate of subjects vaccinated that demonstrate seroconversion via hemagglutination inhibition (HI) antibody titer to each of the three antigens contained in the vaccine 21 days after vaccination. Seroconversion is defined as a ≥ 4-fold increase in HI antibody titer from baseline or a HI antibody titer ≥ 40 when there is no detectable HI antibody titer (HI antibody titer \< 10) at baseline.
Interventions
- BIOLOGICAL Vero cell derived, trivalent, seasonal influenza vaccine
- BIOLOGICAL Licensed egg-derived, trivalent seasonal influenza vaccine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 3,208 participants |
| Start Date | 2008-11 |
| Est. Completion | 2009-07 |
| Phase | Phase 3 |
What the finished NCT00782431 record still lists
NCT00782431 is an interventional study that assigns participants to a tested intervention. Its 3,208 participants enrollment target places it among the larger protocols in the corpus, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (316% higher).
The record links to 0 conditions, and to 2 interventions - of which Vero cell derived, trivalent, seasonal influenza vaccine is the first listed.
NCT00782431 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00782431 about?
NCT00782431 is a clinical study titled "Immunogenicity and Safety Study of an Inactivated Influenza Vaccine (Split Virus, Vero Cell Derived) in Adults Aged 50 Years and Older". The purpose of this study is to demonstrate the effectiveness (seroprotection and seroconversion as measured by the hemagglutination inhibition \[HI\] assay) of an investigational Vero cell-derived, trivalent, seasonal influenza vaccine in adults 50 years of age and older. Subjects will be randomize...
What is the current status of trial NCT00782431?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 3,208 participants. The study started on 2008-11. Estimated completion is 2009-07.
What interventions are being tested in trial NCT00782431?
The interventions under investigation include: Vero cell derived, trivalent, seasonal influenza vaccine (BIOLOGICAL), Licensed egg-derived, trivalent seasonal influenza vaccine (BIOLOGICAL).
Who is sponsoring clinical trial NCT00782431?
This trial is sponsored by Alachua Government Services, which has 12 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00782431's enrollment target sits among peer trials
3,208 73rd of 2000 higher than 1,928 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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