Study of CB-183,315 in Participants With Clostridium Difficile Infection

This is a randomized, double-blind, single-placebo, active-controlled, dose ranging parallel group design with 3 arms. Two dose regimens of CB-183,315 dosed twice daily will be compared with the active comparator oral vancomycin (125 milligrams (mg ) four times daily). Participants with diarrhea at risk for Clostridium difficile infection (CDI) \[for example, received prior or concomitant antibiotic(s)\] will be identified and tested for C. difficile toxin in stool using an enzyme immunoassay (EIA), or polymerase chain reaction (PCR) per the usual standard of care. Eligible participants will be consented, undergo baseline evaluations, and will be randomized in a blinded fashion to one of 3 treatment arms. Participants will be randomized to receive either 125 mg CB-183,315 twice daily alternating with placebo tablets twice daily, 250 mg CB-183,315 twice daily alternating with placebo tablets twice daily or 125 mg oral vancomycin four times dailyover a period of 10 days in a 1:1:1 fashion.