The efficacy and safety of immunotherapy in patients with advanced NSCLC: a systematic review and meta-analysis

Immunotherapy is a novel treatment for advanced non-small cell lung cancer (NSCLC) patients. Immunotherapy includes two main broad classes of therapeutic vaccines and immune checkpoint inhibitors, as well as cytokines, biological response modifiers and cellular therapy. The present systematic review and meta-analysis aims to evaluate the efficacy and safety of different classes of immunotherapy in patients with advanced NSCLC. Literature search was done on Medline, Embase and Cochrane Library. The primary endpoints were overall survival (OS) and grade >= 3 adverse events. Twenty randomized controlled trials were finally identified in our study. Efficacy analysis indicated an improvement of OS in advanced NSCLC patients after treating by therapeutic vaccines and immune checkpoint inhibitors, but not for other immunomodulators. Safety analysis showed that immunotherapy was well-tolerated. All kinds of grade >= 3 adverse events were similar between experimental group and control group except that neutropenia and thrombocytopenia had a higher incidence in patients received vaccines. In conclusion, immunotherapy is a promising treatment for advanced NSCLC patients. Our findings will be further confirmed and supplemented by several phase II and phase III RCTs which are going to complete in near future.