PDCD1 and metastatic melanoma: For instance, a clinical trial conducted FMT in combination with ICI treatment in 10 patients with metastatic melanoma refractory to anti-PD-1 therapy, resulting in clinical responses or extended progression-free survival in a subset of 2 patients attained partial remission, 1 patient achieved complete remission, and 3 patients exhibited progression-free survival (PFS) exceeding 6 months.26 In a separate investigation, 40% of ICI-refractory melanoma patients demonstrated renewed responsiveness to ICIs following FMT.