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A Study to Learn About a Clostridioides Difficile Vaccine in People 65 Years of Age and Older
NCT07282665 · View on ClinicalTrials.gov ↗
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.
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 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT07282665
The ClinicalTrials.gov registry entry for NCT07282665 describes a study currently listed as recruiting. It is categorized as Phase 3, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 32,000 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Pfizer, which has 769 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
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. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT07282665 reports 20 study locations spanning 4 distinct geographic areas — top geographies include California, Alabama, Arizona. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
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. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT07282665?
The interventions under investigation include: Saline Placebo (OTHER), C.difficile vaccine (BIOLOGICAL). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT07282665?
This trial is sponsored by Pfizer, which has 769 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
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.
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