SX-682, a CXCR1 and CXCR2 inhibitor, effectively reduces PMN-MDSC infiltration by blocking CXCR2, thereby slowing tumor progression and synergizing with multiple immunotherapeutic modalities.746–748 A phase I /II clinical trial (NCT04599140) is currently evaluating the efficacy of SX-682 in combination with nivolumab for metastatic colorectal cancer. Here, CXCR2 is linked to metastatic colorectal cancer.