The landscape of immune checkpoint inhibitor plus chemotherapy versus immunotherapy for advanced non‐small‐cell lung cancer: A systematic review and meta‐analysis

BACKGROUND: Lung cancer is the leading cause of cancer-related deaths worldwide and the prognosis remains poor. The recent introduction of the immune checkpoint inhibitor (ICI), or plus chemotherapy, both resulted in the survival benefit for patients with advanced non-small-cell lung cancer (NSCLC), but it remains unanswered which is superior. The current study aimed to estimate the comparative efficacy and safety of ICI-chemotherapy versus ICI-monotherapy in advanced NSCLC. METHODS: Studies were identified by searching PubMed, Embase, and Cochrane library. The randomized controlled trials (RCTs) that ICI monotherapy or ICI plus chemotherapy compared with chemotherapy in NSCLC were included with available primary endpoints of progression-free survival (PFS), overall survival (OS), objective response rate, or treatment-related adverse events. A fixed-effect or random-effects model was adopted depending on between-study heterogeneity. RESULTS: A total of 20 RCTs involving 12,025 patients with NSCLC were included. Both ICI-monotherapy and ICI-chemotherapy resulted in significantly prolonged survival compared to chemotherapy and the former led to significantly longer PFS. The magnitude of survival benefits appeared to be greatest among those treated with pembrolizumab plus platinum-based chemotherapy (OS, 0.56; PFS, 0.54). Additionally, OS and PFS advantages of ICI therapies were observed in patients with NSCLC with low or high programmed cell death 1 ligand 1 (PD-L1) expression level, but not in intermediate PD-L1 TPS. CONCLUSIONS: Pembrolizumab plus platinum-based chemotherapy was recommended as the optimal first-line therapy for advanced patients with NSCLC. Additionally, PD-L1 alone is not recommended as an adequate molecular biomarker to identify eligible patients for routine clinical practice in immunotherapy.