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NCT03090191 · ClinicalTrials.gov registry record · Phase 3
Clostridium Difficile Vaccine Efficacy Trial
A Phase 3 study, sponsored by Pfizer.
- Completed
- Registry status
- Phase 3
- Development phase
- 17,535
- Enrollment target
NCT03090191: Completed Phase 3 study, sponsored by Pfizer.
NCT03090191 is a Phase 3 study that has completed, run by Pfizer. The registered enrollment target is 17,535 participants, above the 771-participant average among 15,282 other Phase 3 trials with a reported enrollment target (2174% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03090191, a Phase 3 study, has completed, sponsored by Pfizer.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 17,535 participants
- Enrollment target
Study Summary
The Clover trial is evaluating an investigational vaccine that may help to prevent Clostridium difficile infection. Participants in the study are adults 50 years of age and older, who are at risk of developing Clostridium difficile infection. The study will assess whether the vaccine prevents the disease, and whether it is safe and well tolerated. Each subject will receive 3 doses of Clostridium difficile vaccine or placebo and be followed for up to 3 years after vaccination for potential Clostridium difficile infection.
Primary Outcome
CDI definition 1 for a primary episode of CDI (no previous CDI onset in the prior 8 weeks) was defined as either a) presence of diarrhea, defined as passage of 3 or more unformed stools (Bristol stool chart types 5-7) in 24 or fewer consecutive hours, and stool sample that was positive for the toxin B gene (by polymerase chain reaction \[PCR)\] and positive for toxin A and/or toxin B, as measured in the central laboratory; or b) Pseudomembranous colitis diagnosed at colonoscopy, at surgery, or h
Interventions
- BIOLOGICAL Placebo
- BIOLOGICAL Clostridium difficile vaccine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 17,535 participants |
| Start Date | 2017-03-29 |
| Est. Completion | 2021-12-21 |
| Phase | Phase 3 |
What the finished NCT03090191 record still lists
NCT03090191 is an interventional study that assigns participants to a tested intervention. Its 17,535 participants enrollment target places it among the larger protocols in the corpus, above the 771-participant average among 15,282 other Phase 3 trials with a reported enrollment target (2174% higher).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT03090191 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03090191 about?
NCT03090191 is a clinical study titled "Clostridium Difficile Vaccine Efficacy Trial". The Clover trial is evaluating an investigational vaccine that may help to prevent Clostridium difficile infection. Participants in the study are adults 50 years of age and older, who are at risk of developing Clostridium difficile infection. The study will assess whether the vaccine prevents the di...
What is the current status of trial NCT03090191?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 17,535 participants. The study started on 2017-03-29. Estimated completion is 2021-12-21.
What interventions are being tested in trial NCT03090191?
The interventions under investigation include: Placebo (BIOLOGICAL), Clostridium difficile vaccine (BIOLOGICAL).
Who is sponsoring clinical trial NCT03090191?
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 NCT03090191's enrollment target sits among peer trials
17,535 11th of 2000 higher than 1,990 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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