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Worried about C. difficile?

Clostridioides difficile, also known as C. difficile or C diff, is a type of bacteria (germ) that lives in the gut. It can produce toxins that can damage the colon.

Did you know:

C. difficile can recur in up to 25% of people after a first episode, and even higher rates after a second episode.

Symptoms of C. difficile

The most common symptoms are:

typically watery, non-bloody diarrhea
a fever
loss of appetite
feeling sick
tummy pain / abdominal cramping

About the Ri-CoDIFy Clinical Trial

Ri-CoDIFy 1 and Ri-CoDIFy 2 are global, Phase 3 clinical studies designed to test how well ridinilazole (study medicine) works in treating C. difficile compared to vancomycin (a standard of care medicine). A positive Phase 3 outcome may allow for the study medicine (ridinilazole) to be approved by regulatory authorities and make it available as a potential option for both the treatment of C. difficile, as well as reducing recurrence.

Both clinical studies are testing for Sustained Clinical Response (SCR) as the primary endpoint, or main measure of success. SCR means that the symptoms of the disease improve after ten days of treatment and the C. difficile infection does not comes back for the next 30 days after the end of treatment.

The Phase 3 clinical studies will also measure the efficacy and safety of ridinilazole, as well as the impact on the patient.

What is involved?

If you join a Ri-CoDIFy clinical study, you will be in the study for about 15 weeks.

We will ask you to take the study medicine tablet (ridinilazole) or a standard of care medicine capsule (vancomycin) four times a day for 10 days. Your part in the study ends 13 weeks later with a safety follow-up visit.

You will remain in contact with the site through visits or calls through the fifteen weeks. Study visits will include health checks, such as medical questionnaires, laboratory assessments, and physical examinations. You will receive care from a study doctor with experience in treating patients with C. difficile and you will be checked regularly.

The cost of the study drug and study-related tests will be covered by the study sponsor, Summit Therapeutics.

What medicine will be tested?

The study drug, ridinilazole, is an investigational medicine because it has not yet been approved to treat people with C. difficile.

It will not be approved for use until clinical studies, such as the Ri-CoDIFy clinical studies, show that it is safe (causes no harm) and effective.

Ridinilazole is an investigational drug being studied for the treatment of C. difficile and is not approved in the US.