A Study of ART24 in Subjects Recently Cured of a Clostridioides Difficile Infection (CDI)

This is a randomized, placebo-controlled, double-blind, multi-site study in which up to approximately 36 subjects with a recent C. difficile infection (CDI) who have completed a standard of care course of CDI antibiotics and have achieved clinical cure based on signs and symptoms, will be randomized to 7 or 28 daily doses of ART24 or placebo. Subjects will be followed for 6 months after the last dose of study drug.

This is a randomized, placebo-controlled, double-blind, multi-site study in which up to approximately 36 subjects with a recent CDI (primary \[meaning the first occurrence they have had\] or recurrent infection) who have completed a standard of care course of CDI antibiotics (vancomycin, fidaxomicin, or metronidazole administered for 10 to 21 days) and have achieved clinical cure based on signs and symptoms, will be randomized to 7 or 28 daily doses of ART24 or placebo. Subjects will be followed for 6 months after the last dose of study drug. Subjects will receive study drug in the following 2 sequential cohorts: * Cohort A: ART24 or placebo once daily for 7 days (8 subjects) * Cohort B: ART24 or placebo once daily for 28 days (28 subjects) In each cohort, subjects will be randomized in a ratio of 3 \[active\]:1 \[placebo\]. Subjects who are randomized to active treatment in both cohorts will receive ART24 (5×10\^9 colony-forming units \[CFU\]) daily. Initiation of Cohort B will only occur once the Data Review Committee (DRC) has evaluated blinded safety data (through Week 2) from Cohort A and recommends that the study proceed to the next cohort.