S2060 Evaluation of Fecal Microbiota, Live-jslm by Standard of Care Antibiotic Washout Period for the Prevention of Recurrent Clostridioides difficile Infection

Introduction: Fecal microbiota, live-jslm (RBL) was approved in November 2022 as the first microbiome-based product for the prevention of recurrent Clostridioides difficile infection (rCDI). RBL is indicated to be rectally administered after 24-72 hours of washout from the standard of care (SoC) antibiotic for rCDI. Various factors contribute to the timely administration of RBL in real-world practice. The study aims to report the outcomes of RBL-treated patients, comparing those receiving RBL within 24-72 hours to those receiving RBL after this timeframe. Methods: This retrospective, multicenter study included patients ≥18 years with rCDI who received RBL in United States physician offices from February 2023 to April 2025, with 8-week follow-up data. Centralized electronic health records were reviewed for patient demographics, comorbidities, rCDI history, risk factors, RBL therapy characteristics, and SoC antibiotic washout period. Recurrence was defined as ≥3 occurrences of diarrhea within 24 hours and was assessed at 8 weeks post-RBL. Patients were evaluated based on the antibiotic washout period: ≤3 days following completion of SoC (Group 1) and >3 days up to 42 days following completion of SoC (Group 2). Pearson’s Chi-Square test was used to test statistical significance. Results: Of the 130 patients who received RBL, 99 patients were in Group 1 and 31 patients were in Group 2. The median days of washout period were 2 days in Group 1 and 9 days in Group 2 (P< 0.0001). The 2 groups had a similar median age (Group 1: 72; Group 2: 71), same median Charlson Comorbidity Index of 4.0, with women being the majority in both. Most patients in both groups had at least 1 risk factor for rCDI, but higher numbers of patients aged ≥65 (74% vs 61%) and non-CDI antibiotic use (18% vs 13%) were observed in Group 1, while a higher number of patients using gastric acid suppressants was observed in Group 2 (37% vs 58%). More patients in Group 1 had a severe presentation of CDI than Group 2 (11% vs 7%). The proportion of patients with inflammatory bowel disease was similar across the groups. Recurrence was seen in 25.3% in Group 1 vs 3.2% in Group 2, where the difference was statistically significant (P = 0.008). Conclusion: These data suggest that RBL continues to be effective in preventing recurrences despite being administered beyond 72 hours after SoC antibiotic washout. Further analysis with a larger cohort is needed to confirm these early results.