6/28/23, 9:50 PM ECOSPOR III Pathway Feedback Search Clinical Topics Home Studies ECOSPOR III ECOSPOR III Disease Clostridioides difficile infection Trial question What is the role of SER-109 microbiome therapy in patients with recurrent C. difficile infection? Study design Multi-center Double blinded RCT Population Characteristics of study participants 60.0% female N = 182 40.0% male 182 patients (109 female, 73 male) Inclusion criteria: patients who had 3 episodes of C. difficile infection Key exclusion criteria: pregnancy; toxic megacolon; small bowel ileus; major gastrointestinal surgery; active IBD; history of fecal microbiota transplantation within 3 months; significant comorbidities Interventions N=89 SER-109 (four daily capsules of SER-109, which contains purified Firmicutes bacterial spores, for 3 days after standard antibiotic treatment) N=93 placebo (matching placebo for 3 days after standard antibiotic treatment) Primary outcome Recurrence of Clostridioides difficile infection 40.0 % 40 https://web.pathway.md/studies/rec9mPp84LIQzBrph 1/2 6/28/23, 9:50 PM ECOSPOR III Pathway 30.0 % 20.0 % Significant decrease 12 10.0 % NNT = 4 0.0 % SER-109 Placebo Significant decrease in recurrence of C. difficile infection (12% vs. 40%; RR 0.32, 95% CI 0.18 to 0.58) Secondary outcomes Borderline significant decrease in recurrence of C. difficile infection in patients aged < 65 years (7% vs. 31%; RR 0.24, 95% CI 0.07 to 0.78) Borderline significant decrease in the rate of recurrence of C. difficile infection in patients aged 65 years (17% vs. 46%; RR 0.36, 95% CI 0.18 to 0.72) Borderline significant decrease in recurrence of C. difficile infection in recipients of vancomycin (16% vs. 38%; RR 0.41, 95% CI 0.22 to 0.79) Safety outcomes No significant difference in adverse events. Conclusion In patients who had 3 episodes of C. difficile infection, SER-109 was superior to placebo with respect to recurrence of C. difficile infection. Reference Paul Feuerstadt, Thomas J Louie, Bret Lashner et al. SER-109, an Oral Microbiome Therapy for Recurrent Clostridioides difficile Infection. N Engl J Med. 2022 Jan 20;386(3):220-229. Open reference URL https://web.pathway.md/studies/rec9mPp84LIQzBrph 2/2