Conversion of unresponsiveness to immune checkpoint inhibition by fecal microbiota transplantation in patients with metastatic melanoma: Study protocol for a randomized phase Ib/IIa trial

The gut microbiome plays an important role in immune modulation. Specifically, presence or absence of certain gut bacterial taxa has been associated with better antitumor immune responses. Furthermore, in trials using fecal microbiota transplantation (FMT) to treat melanoma patients unresponsive to immune checkpoint inhibitors (ICI), complete responses (CR), partial responses (PR), and durable stable disease (SD) have been observed.