At a glance
- What the study gets you
- Access to the study treatment being tested
- Type of study
- Interventional (receives a drug or procedure)
- Time in hospital
- In-person visits at study sites — visit count not specified by the sponsor
- Drug or intervention
- C.difficile vaccine (biological), Saline Placebo (other)
- How long the study runs
- Study runs about 42 months (dates as stated)
- About the drug or intervention
- C.difficile vaccine — biological: C.difficile vaccine given as an intramuscular injection · Saline Placebo — other: 0.9% sodium chloride solution given as a intramuscular injection
- Patient visit burden
- Not specified by the sponsor
- Type of study
- Testing a treatment
- Ages
- 65 Years and over
- Who
- All
- Number of participants
- 32,500
- Started
- 2025-12-10
- Last checked
- 2026-09
Plain English Summary
What is this study?
- • Testing a new treatment for clostridoides difficile associated disease
- • Phase3 - 32,500 participants
- • The purpose of the study is to learn about how effective, safe, and tolerable the Clostridioides difficile (C
Who can take part?
- • Ages 65 Years and over
- • Diagnosed with clostridoides difficile associated disease
Where?
- • Newquay - Newquay Health Centre
- • Exeter - Royal Devon & Exeter Hospital
- • Plymouth - Knowle House Surgery
- • Torquay - Brunel Medical Practice (St Marychurch)
- • +15 more UK sites
This is a simplified summary. Always discuss with your doctor before making any decisions.
About This Trial
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 does not work. 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 clinic 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.
How this trial compares with your answers
Answer 2 more questions to improve match
What we know so far
Still need:
- • Tell us your age for better matching
- • Tell us your sex for better matching
Preliminary match based on your answers. Full eligibility requires on-site assessment including medical history, physical exam, and lab tests. This does not guarantee enrolment.
Eligibility at a Glance
Key info
- Age: 65 Years and over
- Who can join: All genders
What the study is looking for
- ✓Who Can Join the Study (Inclusion Criteria):
- ✓People with recent or future planned contact with healthcare systems, recent antibiotic exposure, or a diagnosis of...
- ✓Who Cannot Join the Study (Exclusion Criteria):
- ✓Anyone who has had CDI before.
- ✓Anyone who has had surgery to remove part of their small or large intestine.
See the full criteria
Where Is This Study? (19 UK sites)
Newquay Health Centre
Newquay TR7 1RU, United Kingdom
Royal Devon & Exeter Hospital
Exeter EX2 5DW, United Kingdom
Knowle House Surgery
Plymouth PL5 3JB, United Kingdom
Brunel Medical Practice (St Marychurch)
Torquay TQ1 4QX, United Kingdom
Panthera Biopartners - Preston
Preston PR2 9QB, United Kingdom
Synexus Scotland Clinical Research Centre
Glasgow ML4 3NJ, United Kingdom
Southampton General Hospital
Southampton SO16 6YD, United Kingdom
Layton Medical Centre
Blackpool FY3 7EN, United Kingdom
Panthera Biopartners - Manchester
Rochdale OL11 4AU, United Kingdom
Panthera Clinic - York
York YO24 4LJ, United Kingdom
Lakeside Surgery
Corby NN17 2UR, United Kingdom
Ormeau Clinical Trials
Belfast BT2 8BG, United Kingdom
Cheadle Community Hospital
Cheadle ST10 1NS, United Kingdom
North Wales Clinical Research Facility
Wrexham LL13 7YP, United Kingdom
Synexus Midlands Clinical Research Centre
Birmingham B16 8QQ, United Kingdom
Panthera Biopartners - Glasgow
Glasgow G51 4RY, United Kingdom
Manchester Royal Infirmary
Manchester M13 9WU, United Kingdom
Synexus Manchester Clinical Research Centre
Manchester M15 6SE, United Kingdom
Panthera Biopartners - Sheffield
Sheffield S2 5FX, United Kingdom
How to Get in Touch
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