Comprehensive analyses of the clinical benefits of immune checkpoint inhibitors in advanced non-small cell lung cancer.

Abstract

168 Background: Treatment with immune checkpoint inhibitors is becoming the standard of care for patients and it was approved for the treatment of non-small-cell lung cancer (NSCLC) growing at a rapid pace. However, selecting patients who are appropriate for therapy and which therapeutic strategies to use can be challenging. Methods: We searched for randomized clinical trials (RCTs) investigating immune checkpoint inhibitors versus observation in patients with advanced NSCLC until September 2017. Overall survival (OS) and progression-free survival (PFS) were pooled by meta-analysis. The GRADE system was used to describe the quality of evidence. Results: The analysis included 11 trials with 5,538 unique patients. High- to moderate-quality evidence indicated that immune checkpoint inhibitors extended NSCLC survival and PFS, expressed as hazard ratios (HRs) (OS: 0.79, P = 0.000; PFS: 0.78, P = 0.000). High- to moderate-quality evidence revealed prolonged OS and PFS were similar across preplanned subgroups in patients with squamous (0.77, P = 0.000 and 0.74, P = 0.001) or nonsquamous disease (0.76, P = 0.003 and 0.73, P = 0.041), EGFR wild-type positive status (0.67, P = 0.000 and 0.59, P = 0.010), current or former smokers (OS: 0.83, P = 0.009), and male (0.79, P = 0.000 and 0.67, P = 0.023). Increasing improvement in OS was associated with increasing PD-L1 expression (TC3 or IC3 HR 0.54, P = 0.000; TC2/3 or IC2/3 HR 0.62, P = 0.007; TC1/2/3 or IC1/2/3 HR 0.64, P = 0.000; TC0 and IC0 HR 0.72, P = 0.017; high- to moderate-quality evidence). In exploratory subgroup analysis suggest that there was advantageous of immune checkpoint inhibitors in previous definitive chemotherapy compared with chemoradiotherapy, with concurrent administration of chemotherapy (OS as HR: P = 0.001, P = 0.006, respectively). Conclusions: This large and comprehensive analysis produced firm evidence that immune checkpoint inhibitors extended advanced NSCLC survival and PFS, while in some patients with EGFR wild-type positive status, current or former smokers, male and higher PD-L1 expression had substantial benefit. The benefits from therapy appear to be influenced by preceding definitive therapy and concurrent chemotherapy.