Recently, the combination of an anti‐CTLA‐4 antibody (ipilimumab) and an anti‐programmed cell death 1 (PD‐1) antibody (nivolumab) has been reported to improve the prognosis of patients with previously untreated advanced non‐small cell lung cancer (NSCLC) in comparison to platinum combination treatment, as evidenced in the CheckMate227 and CheckMate9LA trials.1, 2. Here, PDCD1 is linked to lung cancer.