PDCD1 and lung cancer: However, recent studies have shown that the objective response rate of patients with lung cancer to PD‐1/PD‐L1 inhibitors varies between 20% and 40%, and even for PD‐L1‐high expressed patients with a PD‐L1 tumour proportion score (TPS) ≥ 50%, the response rate is only approximately 50% [4, 5, 6].