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NCT00958126 · ClinicalTrials.gov registry record · Phase 2
A Clinical Trial of CSL's 2009 H1N1 Influenza Vaccine (CSL425) in Healthy Adults in the USA
A Phase 2 study, sponsored by Seqirus.
- Completed
- Registry status
- Phase 2
- Development phase
- 1,313
- Enrollment target
NCT00958126: Completed Phase 2 study, sponsored by Seqirus.
NCT00958126 is a Phase 2 study that has completed, run by Seqirus. The registered enrollment target is 1,313 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (887% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00958126, a Phase 2 study, has completed, sponsored by Seqirus.
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 1,313 participants
- Enrollment target
Study Summary
The purpose of this study is to determine whether CSL425 is a safe and effective vaccine for eliciting an immune response to H1N1 influenza in healthy adults
Primary Outcome
Seroconversion rate: the proportion of participants achieving seroconversion in hemagglutination inhibition (HI) antibody titer. Seroconversion is defined as participants with a baseline titer of less than 1:10 achieving a post-vaccination HI antibody titer of 1:40 or more; or participants with a baseline HI titer of 1:10 or more achieving a four-fold or greater increase in post-vaccination HI titer.
Interventions
- BIOLOGICAL Placebo
- BIOLOGICAL CSL425
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 1,313 participants |
| Start Date | 2009-08 |
| Est. Completion | 2010-04 |
| Phase | Phase 2 |
What the finished NCT00958126 record still lists
NCT00958126 is an interventional study that assigns participants to a tested intervention. Its 1,313 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 (887% higher).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT00958126 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00958126 about?
NCT00958126 is a clinical study titled "A Clinical Trial of CSL's 2009 H1N1 Influenza Vaccine (CSL425) in Healthy Adults in the USA". The purpose of this study is to determine whether CSL425 is a safe and effective vaccine for eliciting an immune response to H1N1 influenza in healthy adults
What is the current status of trial NCT00958126?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 1,313 participants. The study started on 2009-08. Estimated completion is 2010-04.
What interventions are being tested in trial NCT00958126?
The interventions under investigation include: Placebo (BIOLOGICAL), CSL425 (BIOLOGICAL).
Who is sponsoring clinical trial NCT00958126?
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 NCT00958126's enrollment target sits among peer trials
1,313 13th of 2000 higher than 1,988 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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