Antibiotics: The Standard of Care and Predominant Risk Factor Phase 2


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Get the full story of the microbiome

  1. Importance of Microbial Diversity
  2. Dysbiosis and Recurrent C. difficile Infection
  3. Currently Approved Treatment Options
  4. Historic Microbiome Restoration Approaches
  5. Patient and Healthcare Burdens

Currently approved C. difficile infection (CDI) treatments are designed to address the acute infection.

Antibiotic treatment—including vancomycin and fidaxomicin—address the acute infection but do not address (and possibly worsen) dysbiosis or restore the diverse composition of the gut microbiome. This allows a window of vulnerability for recurrence.1-3

Microbiota disruption increases the risk of CDI by providing a niche for C. difficile to flourish. Should antibiotics disrupt the intestinal microbiota, long-lasting effects may result, as well as increased risk of CDI recurrence. Longer exposure to multiple antibiotics and treatment with multiple antibiotics may also increase the risk.4,5

While addressing the acute infection, exposure to antibiotics
may adversely affect the microbiome6,a

Chart depicting exposure to antibiotics and how they may adversely affect the microbiome
Chart depicting exposure to antibiotics and how they may adversely affect the microbiome

Secondary bile acids, which are present in a diverse microbial environment and
may repress C. difficile colonization, decreased after vancomycin.7

Other therapies (eg, bezlotoxumab) do not address the infection or dysbiosis.8

Without addressing existing dysbiosis or restoring the microbiome, reinfection may
begin—impeding microbiome recovery, exacerbating morbidity, and creating a substantial
economic burden.4,5,9-12

BL, baseline.

aNested cohort study compared effects of vancomycin or ridinilazole on fecal microbiota during and after therapy among patients (N=82) enrolled in phase 2 study.

bAfter vancomycin treatment.

C. Difficile infection an Urgent public health threat 30,000 annual mortality


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