Retrospective Analysis of the Safety and Efficacy of Fecal Microbiota, Live-js']jslm (REBYOTA™) Administered Under Enforcement Discretion to Patients With Clostridioides difficile Infection

Background Fecal microbiota, live-jslm (RBL; REBYOTA (TM)), the first microbiota-based live biotherapeutic approved by the US Food and Drug Administration to prevent recurrent Clostridioides difficile infection (rCDI) in adults, has been evaluated in 5 prospective clinical trials. A retrospective analysis considered the safety and efficacy of RBL administered under US Food and Drug Administration enforcement discretion to patients with rCDI and broad eligibility criteria mimicking real-world practice. Methods We retrospectively identified adults with rCDI treated with RBL under enforcement discretion between November 1, 2015, and September 30, 2019, across 5 study sites. CDI diagnosis was based on site-specific practice. The primary safety set (PSS) included all patients who were naive to previous RBL treatment and had continuously comprehensive medical records for 6 months following treatment. Results The primary treatment cohort had 94 patients; the PSS included 64 patients with common comorbidities receiving diverse chronic therapeutics. Most treatment-emergent adverse events were mild to moderate in severity and comparable between comorbidity subgroups and the overall population. There were no serious adverse events related to RBL or the administration procedure. In the PSS, 82.8% of RBL-treated patients responded at 8 weeks, of whom 88.7% had sustained response through 6 months. The number of RBL doses administered had no marked effect on outcome. Conclusions Together with prospective clinical trial outcomes, these findings support the efficacy and safety of RBL to prevent rCDI, with diagnostics and comorbidities representative of real-world clinical practice.