Fidaxomicin Versus Vancomycin for the Treatment of Clostridium Difficile-Associated Diarrhea (CDAD) (MK-5119-018)

Fidaxomicin Versus Vancomycin for the Treatment of Clostridium Difficile-Associated Diarrhea (CDAD) (MK-5119-018)

A Multi-National, Multi-Center, Double-Blind, Randomized, Parallel Group Study to Compare the Safety and Efficacy of 200 mg PAR-101 Taken q12h With 125 mg Vancomycin Taken q6h for Ten Days in Subjects With Clostridium Difficile-Associated Diarrhea

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

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.

Participants receiving fidaxomicin 200 mg capsules orally two times daily (every 12 hours [q12h] regimen) with intermittent matching placebo to fidaxomicin

Participants receiving vancomycin 125 mg capsules orally four times daily (every 6 hours [q6h] regimen).

Matching Placebo to Fidaxomicin administered two times daily (intermittently with fidaxomicin dosing)

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.

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.

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.

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

http://www.merck.com/clinical-trials/pdf/Merck%20Procedure%20on%20Clinical%20Trial%20Data%20Access%20Final_Updated%20July_9_2014.pdf http://engagezone.msd.com/ds_documentation.php

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