RecruitingPHASE2, PHASE3INTERVENTIONAL

Secondary Prevention of Clostridioides Difficile Using Vancomycin

If you've had a C. difficile infection (CDI), it can sometimes come back, especially if you need to take other antibiotics soon after. This study is testing if a medicine called oral vancomycin can help prevent these repeat infections. We'll compare vancomycin to a dummy medicine (a placebo) to see if it makes a difference. Participants will take the study medicine for a short time and will be followed closely with check-ups and questionnaires. The goal is to find better ways to stop C. difficile from returning, which can be a serious problem for many people.

At a glance

Status

Recruiting

Phase

PHASE2, PHASE3

Sponsor

McGill University Health Centre/Research Institute of the McGill University Health Centre

Enrolment target

300

Start

01 Oct 2025

Estimated completion

01 Oct 2029

Clostridioides Difficile Infection Clostridioides Difficile Infection Recurrence Clostridoides Difficile Associated Disease

What is this study about?

Imagine you've had a bad stomach bug caused by a germ called C. difficile. Even after you've been treated and are feeling better, there's a chance it could come back, especially if you get another infection and need to take more antibiotics. This is because antibiotics, while fighting off other germs, can sometimes disrupt the good bacteria in your gut, making it easier for C. difficile to return.

This study is trying to find a way to prevent these repeat C. difficile infections. We're testing a medicine called oral vancomycin, which you take by mouth. The idea is that if you've recently had C. difficile and then need to take other antibiotics, taking a small amount of vancomycin at the same time might protect your gut and stop C. difficile from flaring up again. We're not sure yet how effective this is, which is why we need to do this study.

The study will compare people who take oral vancomycin with those who take a 'placebo' – a dummy pill that looks like the study medicine but contains no active drug. This allows us to see if any benefits are truly due to vancomycin. Finding a way to prevent C. difficile from coming back would be a big step forward, as repeat infections can be very uncomfortable and sometimes serious.

Key takeaways

This study investigates preventing repeat C. difficile infections.
It tests oral vancomycin against a placebo.
Focuses on people who need other antibiotics after a recent C. difficile infection.
Involves taking daily medication and regular check-ins.
Aims to find better ways to manage C. difficile recurrence.
Participation is voluntary and you can withdraw at any time.

Who may be eligible?

This study is looking for adults aged 18 or older who have recently had a C. difficile infection (within the last 120 days). You must have been treated for your C. difficile with vancomycin or fidaxomicin and be feeling better from that infection. Importantly, you also need to be about to start, or have just started (within 3 days), another course of antibiotics that affect your whole body, for a different infection.

There are also some reasons why you might not be able to join. For example, if you were treated for your C. difficile with certain other specific medications like metronidazole alone, or if you're planning to have a procedure called a faecal microbiota transplant. You also need to be able to take medicines by mouth. If you've had surgery to remove your whole large bowel, or if you're allergic to vancomycin, you won't be able to take part.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Have you had a C. difficile infection in the last 4 months (120 days)?
Did you take vancomycin or fidaxomicin for your C. difficile infection and are now better?
Do you need to take other antibiotics for a different infection soon?
Can you take medicines by mouth?
Are you NOT planning to have a 'stool transplant' (faecal microbiota transplant)?

Answer every question to see your result.

What does participation involve?

If you join this study, you will:

* **Take Study Medicine:** You’ll take either the study drug (vancomycin) or a dummy pill (placebo) twice a day. You'll continue this while you are taking your other antibiotics, and then once a day for 7 more days after you finish those antibiotics. * **Attend a Check-up:** You will need to come to a clinic for an in-person follow-up appointment about 8 weeks (56 days) after you start the study. * **Answer Questions:** You'll be asked to fill out weekly questionnaires online or electronically. These will help us understand how you are feeling.

The total duration of your active participation will involve taking the study medicine for a short period (around the time of your other antibiotics) and then some follow-up with the weekly questionnaires and the single in-person visit.

Potential risks and benefits

Participating in a study like this might offer a potential benefit if taking oral vancomycin helps prevent your C. difficile infection from returning. However, there's no guarantee, and you might receive the placebo. Like all medicines, vancomycin can have side effects, and the research team will explain these to you. Your health and safety are very important throughout the study. You are free to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

McGill University Health Centre
Verified postcode
Montreal, Canada· Recruiting

Common questions

What is C. difficile?

It's a type of germ that can cause severe diarrhoea and stomach problems, especially after taking antibiotics.

Why is this study important?

It aims to find out if a common medicine can help stop C. difficile infections from coming back, which is a major problem for some people.

Will I know if I'm taking the real medicine or the dummy pill?

No, you won't know, and neither will your doctors. This helps us get accurate results.

How long will I be in the study?

You'll take the study medicine for a period around when you take other antibiotics, and then you'll have weekly check-ins and one in-person visit.

What if I feel unwell during the study?

You should always tell the study team or your doctor about any new symptoms or concerns you have.

How to find out more

Emily G. McDonald, MD MSc

cdi@idtrials.ca 514-934-1934 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.