Characterization of Clostridium difficile isolates collected during a phase 2b clinical study with SYN-004 (ribaxamase) for the prevention of C. difficile infection

During a Phase 2b study with SYN-004 (ribaxamase) for prevention of Clostridium difficile infection (CDI) conducted in North America and Eastern Europe, 45 C. difficile isolates from subjects with laboratory-confirmed CDI and or colonized with C. difficile were collected and characterized. Several C. difficile PCR ribotypes, including 027 and 198, were identified. •A clinical study collected C. difficile isolates from several countries.•Highly virulent isolates (e.g. RT 027) were found in CDI diarrheal samples.•Non-toxigenic isolates were associated with symptom-free colonization.•SYN-004 prevented CDI caused by various C. difficile ribotypes including RT 027.