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C. difficile Infection

Harnessing the power of the gut microbiota with precision therapeutic innovations that help transform patients' lives

CDI (C. difficile infection)



C. difficile infection (CDI or C. diff.) is an insidious disease which can be debilitating, characterized by watery diarrhea and abdominal cramping and may be accompanied by nausea, fever, and dehydration. C. diff. can also result in more serious disease complications, including bowel perforation (a tear in the gastrointestinal tract), sepsis, and potentially death. It necessitates patient isolation because of its highly contagious nature, making it able to be passed from one person to another either in a hospital or long-term care facility setting, as well as in the community.

C. diff is a bacterial infection caused by the bacteria, Clostridioides difficile, that produces toxins causing inflammation of the colon. And the current standard of care is not solving the complete issue: broad-spectrum antibiotic treatment is a standard therapy for C. diff., but dysbiosis of the gut microbiota due to broad-spectrum antibiotic exposure is also a major risk factor for the disease.  In addition, recurrence following an initial infection is a major issue, where persistent treatment-related dysbiosis predisposes the patient to subsequent recurrence.

Ridinilazole is an investigational therapy that is being studied for the treatment of and the reduction of recurrence of C. difficile infection. Ridinilazole is not approved by any regulatory authority, and commercialization of ridinilazole is subject to regulatory approvals.

Est. 500,000

Cases per year in the US

Est. $5.4 billion

Annual acute care costs, with 20,000 – 30,000 deaths per year in the US

25%+ recurrence

Recurrence is a primary clinical issue in CDI, as up to 25% of initial cases of CDI result in a second episode; the risk of recurrence rises to 65% after a third episode

Urgent Threat

The highest threat designation by the US CDC; C. difficile is one of only four bacteria to carry that label, requiring immediate, aggressive action

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