Fidaxomicin Versus Vancomycin for the Treatment of Clostridium Difficile-Associated Diarrhea (CDAD)

This study has been completed.
Information provided by (Responsible Party):
Merck Sharp & Dohme Corp. Identifier:
First received: April 13, 2006
Last updated: April 27, 2015
Last verified: September 2011

This is a comparative study to investigate the safety and efficacy of fidaxomicin versus vancomycin in subjects with Clostridium difficile-Associated Diarrhea (CDAD).

Condition Intervention Phase
Clostridium Infections
Drug: fidaxomicin
Drug: Vancomycin
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment

Resource links provided by NLM:

Further study details as provided by Merck Sharp & Dohme Corp.:

Primary Outcome Measures:
  • Cure Rate at End of Therapy [ Time Frame: Study day 10 (+/- 2 days) ] [ Designated as safety issue: No ]
    Percentage of participants with 3 or fewer unformed stools for 2 consecutive days and maintained through the end of therapy, and the subject no longer needed specific anti-Clostridium antibacterial treatment after completion of the course of study medication.

Secondary Outcome Measures:
  • Recurrence [ Time Frame: Study days 11-40 ] [ Designated as safety issue: No ]
    Percentage of participants with the re-establishment of diarrhea to an extent(based on frequency of passed unformed stools) that was greater than that noted on the last day of study medication, and the demonstration of either toxin A or B or both of C. difficile, and retreatment with CDI anti-infective therapy was needed.

Other Outcome Measures:
  • Global Cure [ Time Frame: End of Study (Day 40) ] [ Designated as safety issue: No ]
    Percentage of participants who were cured (3 or fewer unformed stools for 2 days through the end of therapy, and no C. difficile therapy after study drug completion) and didn't have recurrence (re-establishment of diarrhea that was greater than on the last day of study drug, positive C. difficile toxin and retreatment with C. difficile therapy) up to Day 40.

Enrollment: 629
Study Start Date: May 2006
Study Completion Date: August 2008
Primary Completion Date: July 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: vancomycin Drug: Vancomycin
125 mg capsules q6hr (4 times a day)
Experimental: fidaxomicin Drug: fidaxomicin
200 mg capsules q12hr (2 times a day)
Other Names:
  • PAR-101
  • OPT-80
  • Dificid

Detailed Description:

The primary objective of this pivotal study is to investigate the safety and efficacy of fidaxomicin versus vancomycin in subjects with Clostridium difficile-associated diarrhea (CDAD). The cure rates at end of therapy and recurrence rates will be evaluated and compared.


Ages Eligible for Study:   16 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Males/females with CDAD
  • Females must use adequate contraception
  • Signed informed consent

Exclusion Criteria:

  • Life-threatening CDAD
  • Toxic megacolon
  • Pregnant
  • Concurrent use of diarrheal agents
  • Participation in other trials
  Contacts and Locations
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Please refer to this study by its identifier: NCT00314951

  Show 58 Study Locations
Sponsors and Collaborators
Merck Sharp & Dohme Corp.
Study Director: Dr. Sherwood Gorbach, MD Optimer Pharmaceuticals, Inc.
  More Information

No publications provided by Merck Sharp & Dohme Corp.

Additional publications automatically indexed to this study by Identifier (NCT Number):

Responsible Party: Merck Sharp & Dohme Corp. Identifier: NCT00314951     History of Changes
Other Study ID Numbers: 101.1.C.003, 101.1.C.003
Study First Received: April 13, 2006
Results First Received: July 1, 2011
Last Updated: April 27, 2015
Health Authority: United States: Food and Drug Administration
Canada: Health Canada
United Kingdom: Medicines and Healthcare Products Regulatory Agency

Keywords provided by Merck Sharp & Dohme Corp.:
CDAD, Clostridium difficile, diarrhea
Clostridium difficile-Associated Diarrhea

Additional relevant MeSH terms:
Clostridium Infections
Bacterial Infections
Gram-Positive Bacterial Infections
Signs and Symptoms
Signs and Symptoms, Digestive
Anti-Bacterial Agents
Anti-Infective Agents
Pharmacologic Actions
Therapeutic Uses processed this record on October 09, 2015