PD-1/L1 With or Without CTLA-4 Inhibitors Versus Chemotherapy in Advanced Non-Small Cell Lung Cancer

BACKGROUND: With the use of immune-checkpoint inhibitors (ICIs) in advanced or metastatic non-small cell lung cancer (NSCLC), whether ICIs or chemotherapy is more effective still remains controversial. This study was conducted to evaluate the efficacy of programmed cell death 1 (PD-1), programmed cell death ligand 1 (PD-L1), cytotoxic T-lymphocyte protein 4 (CTLA-4) alone or in their combination vs chemotherapy in patients with advanced or metastatic NSCLC. METHODS: This meta-analysis was conducted from PubMed, Web of Science, Medline, Embase, and the Cochrane Library up to March 2021 to identify relevant randomized controlled trials. Primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary endpoint was adverse events (AEs). This meta-analysis’s Prospero registration number is CRD42022323570. RESULTS: The search process has identified 13 studies containing 7918 patients with advanced or metastatic NSCLC. The benefit of PD-1/L1 or CTLA-4 inhibitors alone or in combination compared with chemotherapy for advanced or metastatic NSCLC was elucidated in both OS [HR = .75, 95% CI (.70-.80), P < .001] and PFS [HR = .83, 95% CI (.73-.95), P < .001]. Besides, ICIs were associated with fewer AEs compared to chemotherapy. CONCLUSION: PD-1/L1 or CTLA-4 inhibitors alone or in combination, with fewer AEs, was associated with significant improvements in terms of OS and PFS than chemotherapy in advanced or metastatic NSCLC.