Inclusion Criteria: 

• Able and willing to provide written informed consent.
• Subjects with a qualifying CDI episode who have a prior history of CDI diarrhea or first occurrence of CDI diarrhea with a higher risk for recurrence (≥ 65 years of age).
• CDI symptoms must have started within 30 days (inclusive) prior to the day of randomization.
• The diarrhea is considered unlikely to have another etiology. 
• Complete an Investigator's choice SOC antibiotic regimen of a minimum of 10 days and up to 21 days of total duration.
• Have a positive C. difficile stool.
• Recovered from any complications of severe or fulminant CDI and clinically stable by the time of randomization.

Exclusion Criteria:

• History of diarrhea (defined as 3 or more loose stools per day lasting for at least 4 weeks) that is not related to C. difficile infection within the 3 months prior to randomization. 
• Known or suspected toxic megacolon and/or known small bowel ileus at the time of randomization. 
• Contraindication to oral/enteral therapy (e.g., severe reflux, severe nausea/vomiting, or ileus). 
• Prior administration of genetically modified investigational live bacterial/fungal/bacteriophage/viral isolates for CDI-associated diarrhea.
• History of administration of fecally-derived investigational live biotherapeutic products, or fecally-derived live bacterial isolates for CDI-associated diarrhea including fecal microbiota transplantation (FMT) within the last 6 months. 
• Use of drugs that alter gut motility.
• History of acute leukemia or hematopoietic stem cell transplantation or myelosuppressive chemotherapy within 2 months prior to randomization. 
• Subjects with compromised immune system.
• Major gastrointestinal surgery (e.g., significant bowel resection or diversion) within 3 months prior to randomization or any history of total colectomy or bariatric surgery that disrupts the gastrointestinal lumen. 
• History of confirmed celiac disease, inflammatory bowel disease, short gut, gastrointestinal tract fistulas, or ischemia.