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

To be eligible for enrollment, a participant must meet all of the following criteria prior to any study related procedures: * Informed Consent obtained and signed * Age ≥ 18 years * If female, participant is non-lactating, and is either: * Not of childbearing potential, defined as postmenopausal for at least 1 year or surgically sterile due to bilateral tubal ligation, bilateral oophorectomy, or hysterectomy * Of childbearing potential and is practicing the barrier method of birth control along with one of the following methods: oral or parenteral contraceptives for 3 months prior to study drug administration, a vasectomized partner, or abstinence from sexual intercourse * Established non-severe or severe CDI (after Data Monitoring Committee \[DMC\] review) with a positive stool test for toxin A and/or B within 72 hours prior to first dose of study drug. Exclusion Criteria: A participant will not be enrolled if s/he meets any of the following criteria: * Female and pregnant or lactating * Toxic megacolon and/or known small bowel ileus * Received treatment with intravenous (IV) immune globulin within 30 days prior to the first dose of study drug * Antibacterial therapy specific for current CDI or that may be effective for CDI even if given for a different indication: * Received more than 24 hours of oral vancomycin for the current episode of CDI prior to first dose of study drug. * Received more than 24 hours of oral/intravenous metronidazole OR any other therapy specific for the current episode of CDI immediately prior to first dose of study drug unless the participant received at least 3 days of such therapy, and is considered a treatment failure for CDI. * Received more than 24 hours of oral/intravenous metronidazole for any other indication in the 3 days prior to first dose of study drug. * Participants with more than 2 episodes of CDI within 90 days (that is, participants can be enrolled with their 1st recurrence/2nd episode) * Major gastrointestinal (GI) surgery (that is, significant bowel resection including total colectomy with ileostomy) within 3 months of enrollment (this does not include appendectomy or cholecystectomy) * History of prior inflammatory bowel disease: ulcerative colitis, Crohn's disease, or microscopic colitis * Unable to stop loperamide, diphenoxylate, and cholestyramine during the duration of the study * Unable to stop opiate treatment, unless on a stable dose as of onset of diarrhea and no change in dose planned for the duration of the study * Known positive stool cultures for other enteropathogens, including but not limited to Salmonella, Shigella and Campylobacter * Known stool studies positive for ova and/or parasites * Known intolerance or hypersensitivity to daptomycin and/or vancomycin * Poor concurrent medical risks with clinically significant co-morbid disease such that in the opinion of the Investigator the participant should not be enrolled * Received an investigational drug or participated in any experimental procedure within 1 month prior to study entry * Previously enrolled in this study * Received an investigational vaccine against C. difficile * Participants with known Hepatitis B or Hepatitis C who have alanine aminotransferase or aspartate aminotransferase \> 2.5 times the upper limit of normal (ULN) and/or bilirubin \> 1.5 times the ULN * Human immunodeficiency virus positive, unless controlled (that is, on triple therapy) and with a CD4 \> 200 cells per millimeter cubed (cellsmm˄3) * Anticipated that systemic antibacterial therapy for a non-CDI infections will be required for \>7 days after start of study therapy * Concurrent therapy with daptomycin * Unable to discontinue Saccharomyces or similar probiotic * Known active IV drug or alcohol abuse * Concurrent intensive chemotherapy, radiotherapy or biologic treatment for active malignancy (may only be enrolled after consultation with Medical Monitor) * Unable to comply with the protocol requirements * Any condition that, in the opinion of the Investigator, might interfere with study objectives * Life expectancy is less than 6 weeks Additional Exclusions for Participants with Severe CDI In addition to the criteria listed above, a participant who meets the definition of severe CDI will not be enrolled if the participant meets any of the following criteria: * Age \> 80 * Hypotension, defined by sustained systolic blood pressure \< 90 millimeters of mercury (mmHg), or need for vasopressors to maintain blood pressure * Abdominal rebound tenderness on examination * Acute kidney insufficiency defined by: * oliguria (\< 20 cubic centimeter \[cc\] urine output per hour over a 4 hour period not responsive to attempts to increase renal perfusion) or * non-perfusion (for example, pre-renal) related azotemia with initial creatinine (Baseline) \> 2.5 milligrams per deciliter (mg/dL) and blood urea nitrogen (BUN) \> 40 mg/dL with no prior history of chronic kidney disease * Unable to tolerate oral medications due to persistent vomiting 2. White blood cell (WBC) count \> 30,000/mm˄3