Correlation between immune-related adverse events and the efficacy of PD-1/PD-L1 inhibitors in the treatment of non-small cell lung cancer: systematic review and meta-analysis

Anti-programmed cell death-1 and programmed cell death ligand-1 (PD-1/PD-L1) inhibitors have been proved to have a significant clinical efficacy in the treatment of non-small cell lung cancer (NSCLC). Many studies have demonstrated that immune-related adverse events (irAEs) are significantly correlated with clinical efficacy, but the results are not consistent. This meta-analysis aimed to evaluate the associations between irAEs and efficacy. Comprehensive searches were conducted on PubMed and EMBASE database. The HR and 95% CI were used to assess the associations between immune-related adverse events and efficacy of overall survival and progression-free survival. Subgroup analyses were performed based on irAEs type and grade of irAEs. Heterogeneity and publication bias were also assessed by Q test, I2, and funnel plot. Compared with non-irAEs, the development of irAEs was significantly improved PFS and OS (PFS: HR = 0.55, 95% CI = 0.51–0.60, p < 0.001; OS: HR = 0.74, 95% CI = 0.68–0.81, p < 0.001). In the subgroup analyses, the occurrence of endocrine irAEs, gastrointestinal irAEs, skin lesions and low-grade irAEs was also significantly correlated with the efficacy. Additionally, the association between severe-grade irAEs and survival benefits on PFS was significant, but not on OS. The results indicated that the occurrence of irAEs was significantly associated with a better efficacy in the treatment of NSCLC, especially endocrine, gastrointestinal, skin and low-grade irAEs.