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Clover Clinical Trial

Clover - Clostridium difficile vaccine efficacy trial

Spending a lot of time at the doctor?

Learn about a study of an investigational vaccine for people who may be at risk of Clostridium difficile (C. diff).

What is Clostridium difficile?

C. difficile (C. diff) is one of the most common causes of health care-related infections. C. diff is a type of bacteria that lives in the human intestines and its spores can survive outside of the body for months. These spores are resistant to cleaning and are most commonly transmitted in health care settings. People can become infected by touching surfaces that are contaminated or by coming into contact with a health care worker that has the bacteria or spores on their hands. People most at risk of getting sick due to C. diff are those who are taking antibiotics, being treated in a health care facility, the elderly and people who are already ill. This infection can cause symptoms that include frequent diarrhea, inflammation of the colon, fever, nausea and abdominal pain; in severe cases it can be life-threatening. The Clover Trial is evaluating an investigational vaccine that may help decrease your chance of getting sick due to C. diff.

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Learn More

To learn more, please contact:
Mariana Bernui, PhD

About the Clover Trial

Your participation in this study is expected to last between 18 and 42 months and will require approximately 5 office visits over the first 7 months of participation. Approximately 16,000 patients are expected to participate in the study globally. During the study, you will be given an electronic diary and asked to record any symptoms you might be having. If you have diarrhea 3 or more times within 24 hours, you will be asked to collect a sample of the diarrhea. We will provide a kit for this and arrange for a courier to collect the sample.

You may also have the following assessments during the study period: physical exam, vital signs, urine tests and stool sample(s). All participants will be asked to provide blood samples.

You will be randomly assigned (like the flip of a coin) to receive either the investigational study vaccine or a placebo. This product will be given to you by injection. The placebo looks like the study vaccine, but has no active ingredient in it. You will not know if you are receiving the active vaccine or the placebo.

Why Should I Participate?

The purpose of the Clover trial is to evaluate the safety and efficacy of an investigational vaccine in reducing the changes of getting sick due to C. diff. The knowledge gained from this study may help others in the future.

The clinical research team will discuss all study risks with you and answer any additional questions you may have.

How to Participate

If you are interested in participating, you will go through a series of screening assessments to determine your eligibility. If you qualify and choose to participate, you will be randomly assigned to receive the investigational vaccine or a placebo. Eligible participants will receive study related tests and procedures at no cost.

Am I Eligible?

You may be eligible to participate in this clinical study if you:

  • Are 50 years old or over
  • Have had at least 2 visits to the emergency room, or had a hospitalization of at least 2 nights in the last 12 months, or
  • Have a planned hospitalization that will require a stay of 2 or more nights, or
  • Are a resident in a nursing facility, or
  • Have had at least 10 outpatient visits in the last 12 months, or
  • Have received oral or injectable antibiotics within the last 12 weeks

Note: These are not the only eligibility criteria for this clinical research study, and other criteria may exclude you. A clinical research team member will help determine if you meet all necessary criteria to participate.

The information on these pages is provided for general information only and should not be used for diagnosis or treatment, or as a substitute for consultation with a physician or health care professional. If you have specific questions or concerns about your health, you should consult your health care professional.

The images being used are for illustrative purposes only; any person depicted is a model.

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