Notably, the Chemo + PD-1 + BMS regimen exhibited significantly lower risks of severe thrombocytopenia (compared with the Chemo + PD-1 regimen: RR, 0.21; 95%CI, 0.05–0.63; compared with the Chemo + PD-L1 regimen: RR, 0.16; 95%CI, 0.03–0.49) and anemia (compared with the Chemo + PD-1 regimen: RR, 0.19; 95%CI, 0.03–0.74; compared with the Chemo + PD-L1 regimen: RR, 0.22; 95%CI, 0.03–0.87) compared with the current first-line SOC. Here, PDCD1 is linked to Thrombocytopenia.