Efficacy of PD‐1/PD‐L1 inhibitors in patients with advanced non‐small cell lung cancer: A meta‐analysis of randomized clinical trials

BACKGROUND: This meta‐analysis systematically evaluated the efficacy of PD‐1 and PD‐L1 inhibitors for the treatment of advanced non‐small cell lung cancer (NSCLC) and investigated the efficacy of first‐line therapy and PD‐1 versus PD‐L1 inhibitors. METHODS: PubMed, The Cochrane Library, and Embase were searched up to November 2018 for randomized controlled trials (RCTs) for eligible studies. The outcome of interest was overall survival (OS). The methodology was based on the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses and Cochrane Collaboration guidelines. Data were pooled by using the random effects model and expressed as hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). Heterogeneity was assessed and quantified (I (2)). RESULTS: Seven RCTs were included in this study. PD‐1/PD‐L1 inhibitors achieved superior OS compared to chemotherapy (HR 0.72, 95% CI 0.63–0.82; P < 0.0001). OS was superior in previously treated patients compared to untreated patients (HR 0.69, 95% CI 0.63–0.76; HR 0.82, 95% CI 0.47–1.44, respectively). No significant differences in OS were observed between PD‐1 and PD‐L1 inhibitors (HR 0.71, 95% CI 0.59–0.86; HR 0.73, 95% CI 0.63–0.84, respectively). CONCLUSIONS: PD‐1/PD‐L1 inhibitors significantly prolonged the OS of previously treated patients. No significant differences in OS were observed between PD‐1 and PD‐L1 inhibitors.