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NCT07282665 · ClinicalTrials.gov registry record · Phase 3
A Study to Learn About a Clostridioides Difficile Vaccine in People 65 Years of Age and Older
A Phase 3 study of Clostridioides Difficile Associated Disease, sponsored by Pfizer.
- Recruiting
- Registry status
- Phase 3
- Development phase
- 32,000
- Enrollment target
- 20
- Study locations
NCT07282665: Recruiting Phase 3 study of Clostridioides Difficile Associated Disease, sponsored by Pfizer.
NCT07282665 is a Phase 3 study of Clostridioides Difficile Associated Disease that is actively recruiting participants, run by Pfizer. The registered enrollment target is 32,000 participants, above the 770-participant average among 15,282 other Phase 3 trials with a reported enrollment target (4056% higher). The trial reports 20 study locations across 4 states. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT07282665, a Phase 3 study of Clostridioides Difficile Associated Disease, is actively recruiting participants, sponsored by Pfizer.
- RECRUITING
- Registry status
- Phase 3
- Development phase
- 32,000 participants
- Enrollment target
- 20
- Study locations
Study Summary
The purpose of the study is to learn about how effective, safe, and tolerable the Clostridioides difficile (C. difficile) vaccine is in decreasing the number of C. difficile infections (pCDI) in adults 65 years of age or older. The participants will receive either the C. difficile vaccine or placebo (saline). A placebo does not contain any active ingredients. The vaccines will be given as a shot into the upper arm muscle. This study looks at the number of diarrhea (loose stools) events related to a C. difficile infection, so the length of the study can change. If these events happen quickly, the study may finish sooner; if they happen slowly, it could take longer. Sometimes, the study might stop early if the vaccine clearly works or clearly doesn't. Participants will stay in the study until enough events have occurred to answer the main question. On average, each person is expected to take part for up to about three and a half years. During this time, participants will have 3 planned clinical visits and 3 planned phone visits. After these visits, more scheduled clinic visits will happen every year until the end of study. Besides the scheduled study visits, if at any time during the study a participant has 3 or more loose stools in 24 hours, they will be asked to save the next one (the fourth or later) and contact the study site. The study site will check to see if it could be a C. difficile infection. This check may happen at the clinic or through a phone or video call.
Primary Outcome
Injection site pain, redness, and swelling as self-reported in electronic diaries
Conditions Studied
Interventions
- OTHER Saline Placebo
- BIOLOGICAL C.difficile vaccine
Study Locations (20)
California
- Kaiser Permanente Daly City - Daly City
- Kaiser Permanente Los Angeles Medical Center - Los Angeles
- Kaiser Permanente Oncology Pharmacy #014C - Los Angeles
- Kaiser Permanente Oakland - Oakland
- Kaiser Permanente Ontario Medical Center - Ontario
- Kaiser Permanente Roseville - Roseville
- Kaiser Permanente Sacramento - Sacramento
- Kaiser Permanente South Sacramento - Sacramento
- Velocity Clinical Research, San Bernardino - San Bernardino
- Kaiser Permanente - San Diego Medical Center - San Diego
- Kaiser Permanente Viewridge Medical Office - San Diego
- Kaiser Permanente San Jose - San Jose
- Carbon Health - San Mateo - Hillsdale Mall - San Mateo
- Kaiser Permanente Santa Clara - Santa Clara
- Med Partners, Inc. dba Premiere Medical Center of Burbank, Inc. - Toluca Lake
Alabama
- North Alabama Research Center - Athens
- Lakeview Clinical Research - Guntersville
- Medical Affiliated Research Center - Huntsville
Arizona
- Epic Medical Research-Sun City - Sun City
Arkansas
- Applied Research Center of Arkansas - Little Rock
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 32,000 participants |
| Start Date | 2025-12-10 |
| Est. Completion | 2029-06-07 |
| Phase | Phase 3 |
What NCT07282665 shows while recruiting
NCT07282665 is an interventional study that assigns participants to a tested intervention. Its 32,000 participants enrollment target places it among the larger protocols in the corpus, above the 770-participant average among 15,282 other Phase 3 trials with a reported enrollment target (4056% higher).
The record links to 1 condition, with Clostridioides Difficile Associated Disease appearing as the primary indexed condition, and to 2 interventions - of which Saline Placebo is the first listed.
NCT07282665 names 20 study sites across 4 states, led by California, Alabama, Arizona.
Frequently Asked Questions
What is clinical trial NCT07282665 about?
NCT07282665 is a clinical study titled "A Study to Learn About a Clostridioides Difficile Vaccine in People 65 Years of Age and Older". The purpose of the study is to learn about how effective, safe, and tolerable the Clostridioides difficile (C. difficile) vaccine is in decreasing the number of C. difficile infections (pCDI) in adults 65 years of age or older. The participants will receive either the C. difficile vaccine or placeb...
What is the current status of trial NCT07282665?
This trial is currently recruiting. It is a Phase 3 study. The enrollment target is 32,000 participants. The study started on 2025-12-10. Estimated completion is 2029-06-07.
What conditions does trial NCT07282665 study?
This clinical trial studies the following conditions: Clostridioides Difficile Associated Disease.
What interventions are being tested in trial NCT07282665?
The interventions under investigation include: Saline Placebo (OTHER), C.difficile vaccine (BIOLOGICAL).
Who is sponsoring clinical trial NCT07282665?
This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT07282665 being conducted?
This trial has 20 study locations across Alabama, Arizona, Arkansas, California. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT07282665's enrollment target sits among peer trials
32,000 5th of 2000 higher than 1,996 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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