Clinical Efficacy of Immune Checkpoint Inhibitors in Older Non-small-Cell Lung Cancer Patients: A Meta-Analysis

Background:Immune checkpoint inhibitors (ICIs) have transformed the treatment landscape among non-small-cell lung cancer (NSCLC) patients. The efficacy of ICI therapy in older patients (>= 65 years) is controversial and not fully clarified. We performed a systematic review and meta-analysis to evaluate the efficacy of ICIs in patients with advanced or metastatic NSCLC based on age (<65 years vs. >= 65 years). Methods:A comprehensive literature search for eligible randomized control phase II/III trials that compared the efficacy of anti-PD-1/PD-L1 agents against chemotherapy in advanced or metastatic NSCLC patients. Pooled overall survival (OS) and progression-free survival (PFS) estimates were calculated based on random/fixed effects models according to the heterogeneity between the studies. Results:A total of 10 studies involving 8 randomized controlled trials (2 updates) were enrolled in this meta-analysis [2,662 young patients (<65 years) and 1,971 older patients (>= 65 years)]. The efficacy of anti-PD-1/PD-L1 agents is comparable between young (<65 years) and older (>= 65 years) patients for OS [HR 0.75 95% CI (0.64-0.88) vs. 0.76 95% CI (0.66-0.87)]. However, our pooled analysis was not sufficient to show a significant benefit in terms of PFS for anti-PD-1/PD-L1 agents [HR 0.87 95% CI (0.74-1.01),P= 0.06]. In addition, we failed to see a PFS superiority of anti-PD-1/PD-L1 agents against chemotherapy in two age subgroups [<65 years and >= 65 years, HR 0.85 95% CI (0.72-1.01),P= 0.07 and HR 0.87 95% CI (0.68-1.10),P= 0.25]. Conclusion:ICIs therapy presents comparable efficacy in older advanced or metastatic NSCLC patients with young patients.