Efficacy and safety of PD1/PDL1 blockades versus docetaxel in patients with pretreated advanced non-small-cell lung cancer: a meta-analysis

BACKGROUND: PD1/PDL1 blockade is a promising treatment for patients with non-small-cell lung cancer (NSCLC). Here, we employed meta-analysis to evaluate the efficacy and safety of PD1/PDL1 blockades for previously treated NSCLC patients. METHODS: Randomized clinical trials were retrieved by searching electronic databases. Data for HRs, 95% CIs for overall survival (OS), progression-free survival (PFS), and adverse events (AEs) were extracted and pooled. RESULTS: A total of five randomized controlled trials including 2,910 patients were included in this meta-analysis. Pooled HRs (95% CI) were 0.71 (0.63–0.79, P<0.0001) for OS and 0.86 (0.73–1.02) for PFS. In the subgroup analysis, the pooled HR (95% CI) for PFS was 0.82 (0.75–0.91, P<0.0001) in patients with high PDL1 expression, but no significant difference was seen in patients with low expression (0.97 [0.76–1.24], P=0.82). The pooled RR for treatment-related AEs of all grades was 0.32 (0.27–0.38, P<0.00001) compared with the docetaxel arm, while that for grade 3–5 treatment-related AEs in the PD1/PDL1-blockade arm was 0.16 (0.10–0.27, P<0.00001). CONCLUSION: PD1/PDL1 blockades enhanced OS and PFS and led to lower risk of AEs in NSCLC patients. Smoking history and wild-type EGFR were associated with extended OS.