527 Digital spatial profiling of paired tumor biopsies reveals indoleamine 2,3-dioxygenase (IDO)1 as a potential resistance mechanism for a tumor-targeted 4–1BB agonist in patients with solid tumors
527 Digital spatial profiling of paired tumor biopsies reveals indoleamine 2,3-dioxygenase (IDO)1 as a potential resistance mechanism for a tumor-targeted 4–1BB agonist in patients with solid tumors