Predictive effect of molecular and clinical characteristics for the OS and PFS efficacy of anti-PD-1/PD-L1 immunotherapy in patients with NSCLC: a meta-analysis and systematic review

OBJECTIVE: To evaluate the predictive effect of molecular and clinical characteristics for the efficacy of anti-programmed cell death 1 (PD-1)/programmed cell death ligand-1 (PD-L1) immunotherapy in patients with non-small cell lung cancer (NSCLC). DESIGN: Systematic review and meta-analysis. SETTING: Twelve randomised controlled trials (RCTs) with 7442 patients were retrieved from all over the world. METHODS: Electronic databases were searched for eligible RCTs. The HRs and 95% CIs for overall survival (OS) and progression‐free survival (PFS) for the whole and subgroup population were extracted for meta-analysis using Review Manager V.5.3 software. PRIMARY AND SECONDARY OUTCOME MEASURE: OS was the primary outcome and PFS was the secondary outcome. RESULTS: Twelve RCTs with 7442 patients were included. For the trial population, anti-PD-1/PD-L1 immunotherapy significantly improved OS (HR=0.78, 95% CI 0.70 to 0.86, p<0.00001) and objective response rate (ORR) (risk ratio=1.37, 95% CI 1.08 to 1.74, p=0.009). Subgroup analysis results showed an improved OS at PD-L1≥1%, ≥5% and ≥50% levels, and a longer PFS at PD-L1≥5% and ≥50% levels. Moreover, OS and PFS benefits were observed in the non-first line treatment, squamous cell carcinoma histology, male, smoking, non-central nervous system (CNS) metastasis, epidermal growth factor receptor (EGFR) wild-type and Kirsten rat sarcoma viral oncogene homolog (KRAS) mutant subgroups. CONCLUSIONS: Anti-PD-1/PD-L1 immunotherapy significantly improved OS and ORR and reduced the rate of Adverse Events (AEs) compared to chemotherapy. PD-L1 expression, line of therapy, histology, sex, smoking history, CNS metastases, EGFR and KRAS mutational status might be potential predictors for the therapeutic effect of anti-PD-1/PD-L1 immunotherapy in specific patients with NSCLC.