Efficacy and Safety of Antigen-specific Immunotherapy in the Treatment of Patients with Non-small-cell Lung Cancer: A Systematic Review and Meta-analysis

Background and Objective: We performed this systematic review and meta-analysis to assess the efficacy and safety of antigen-specific immunotherapy (Belagenpumatucel-L, MAGE-A3, L-BLP25, and TG4010) in the treatment of patients with non-small-cell lung cancer (NSCLC). Methods: A comprehensive literature search on PubMed, Embase, and Web of Science was conducted. Eligible studies were clinical trials of patients with NSCLC who received the antigenspecific immunotherapy. Pooled hazard ratios (HRs) with 95% confidence intervals (95%CIs) were calculated for overall survival (OS), progression-free survival (PFS). Pooled risk ratios (RRs) were calculated for overall response rate (ORR) and the incidence of adverse events. Results: In total, six randomized controlled trials (RCTs) with 4,806 patients were included. Pooled results showed that, antigen-specific immunotherapy did not significantly prolong OS (HR=0.92, 95%CI: 0.83, 1.01; P=0.087) and PFS (HR=0.93, 95%CI: 0.85, 1.01; P=0.088), but improved ORR (RR=1.72, 95%CI: 1.11, 2.68; P=0.016). Subgroup analysis based on treatment agents showed that, tecemotide was associated with a significant improvement in OS (HR=0.85, 95%CI: 0.74, 0.99; P=0.03) and PFS (HR=0.70, 95%CI: 0.49, 0.99, P=0.044); TG4010 was associated with an improvement in PFS (HR=0.87, 95%CI: 0.75, 1.00, P=0.058). In addition, NSCLC patients who were treated with antigen-specific immunotherapy exhibited a significantly higher incidence of adverse events than those treated with other treatments (RR=1.11, 95%CI: 1.00, 1.24; P=0.046). Conclusion: Our study demonstrated the clinical survival benefits of tecemotide and TG4010 in the treatment of NSCLC. However, these evidence might be limited by potential biases. Therefore, further well-conducted, large-scale RCTs are needed to verify our findings.