Immune checkpoint inhibitors (ICIs), such as anti‐cytotoxic‐T‐lymphocyte‐associated antigen 4 (anti‐CTLA4) (ipilimumab), anti‐programmed cell death 1 (anti‐PD1) (nivolumab, pembrolizumab, and cemiplimab) and anti‐programmed cell death ligand 1 (anti‐PD‐L1) (atezolizumab, avelumab, and durvalumab), have recently changed the therapeutic paradigm for patients across multiple cancer types.1 The gene discussed is PDCD1; the disease is cancer.