Therapeutic effects and associated adverse events of PD-1 and CTLA-4 pathway inhibitors in the treatment of non-small-cell lung cancer: meta-analyses of clinical phase II/III randomized controlled trials

Objective: To summarize and compare the therapeutic efficacy of programmed death 1 (PD-1) and cytotoxic T lymphocyte associated antigen 4 (CTLA-4) pathway inhibitors in the treatment of non-small-cell lung cancer (NSCLC). Methods: Traditional and network meta-analysis of clinical phase II/III randomized controlled trials of PD-1 and CTLA-4 pathway inhibitors vs. controls (general chemotherapy or best support therapy) in the treatment of NSCLC was performed by RevMan and ITC programs. The data of progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and grade 3/4 AE were extracted to evaluate the prognosis, tumor responses, and toxicity, respectively. Results: Among patients with NSCLC, when compared with controls, PD-1 pathway inhibitors had longer median OS, higher ORR, and lower incidence of grade 3 or 4 AE; further CTLA-4 pathway inhibitors had higher ORR. When compared with CTLA-4 pathway inhibitors, PD-1 pathway inhibitors had significant higher OS and lower incidence of grade 3 or 4 AE. Conclusion: Because the PD-1 pathway inhibitors have more advantages in patients’ survival, tumor response, and adverse events than CTLA-4 pathway inhibitors and traditional treatment, this agents could prioritize to use for the treatment of NSCLC.