Impact of the combined timing of PD-1/PD-L1 inhibitors and chemotherapy on the outcomes in patients with refractory lung cancer

•The cytotoxic effects of chemotherapeutic drugs were positively correlated with the activation states of PBMCs.•Administering the anti-PD-1 Ab 3 days after chemotherapy resulted in weaker cytotoxic effects on lymphocytes in vitro.•Administering PD-1/PD-L1 inhibitors a few days after chemotherapy resulted in better survival in lung cancer patients.