Immune-mediated Colitis (IMC)

Multiple retrospective studies suggest that the administration of corticosteroids to treat irAEs is safe, and does not compromise efficacy of ICI therapy in cancer patients. While \~67% of patients respond to corticosteroids, 33% of patients require biologic therapy such as TNFα inhibitors (e.g. infliximab), integrin α4β7 inhibitors (e.g. vedolizumab), or JAK/STAT inhibitors (e.g. tofactinib). This study aims to determine that distinct pathobionts govern the development of irCAE and IMC; and that the administration of hdFMT may reverse steroid-refractory irCAEs or IMC. The use of hdFMT has been shown to be effective in steroid and biologic (TNFα and/or integrin α₄β₇ inhibitor) refractory colitis in PD-1 and/or CTLA-4 ICI treated cancer patients in single-institution case series.