Comparative effectiveness of combined therapy inhibiting EGFR and VEGF pathways in patients with advanced non-small-cell lung cancer: a meta-analysis of 16 phase II/III randomized trials

BACKGROUND & AIMS Combined therapy inhibiting EGFR and VEGF pathways is becoming a promising therapy in the treatment of advanced non-small-cell lung cancer (NSCLC), however, with controversy. The study aims to compare the efficacy of combined inhibition therapy versus control therapy (including placebo, single EGFR inhibition and single VEGF inhibition) in patients with advanced NSCLC. MATERIALS AND METHODS An adequate literature search in EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), American Society of Clinical Oncology (ASCO) and European Society of Medical Oncology (ESMO) was conducted. Phase II or III randomized controlled trials (RCTs) that compared effectiveness between combined inhibition therapy and control therapy in patients with advanced NSCLC were eligible. The endpoint was overall response rate (ORR), progression free survival (PFS) and overall survival (OS). RESULTS Sixteen phase II or III RCTs involving a total of 7,109 patients were included. The results indicated that the combined inhibition therapy significantly increased the ORR (OR = 1.59, 95% CI = 1.36-1.87, p<0.00001; I2 = 36%) when compared to control therapy. In the subgroup analysis, the combined inhibition therapy clearly increased the ORR (OR = 2.04, 95% CI = 1.60-2.60, p<0.00001; I2 = 0%) and improved the PFS (HR = 0.78, 95% CI = 0.71-0.85, p<0.00001;I2 = 0%) when compared with the placebo, and similar results was detected when compared with the single EGFR inhibition in terms of ORR (OR = 1.39, 95% CI = 1.12-1.74, p = 0.003; I2 = 30%) and PFS (HR = 0.73, 95% CI = 0.67-0.81, p<0.0001; I2 = 50%). No obvious difference was found between the combined inhibition therapy and single VEGF inhibition in term of ORR, however, combined inhibition therapy significantly decreased the PFS when compared to the single VEGF inhibition therapy (HR = 1.70, 95% CI = 1.34-2.17, p<0.0001; I2 = 50%). Besides, no significant difference was observed between the combined inhibition therapy and control therapy in term of OS (including placebo, single EGFR inhibition and single VEGF inhibition) (HR = 0.98, 95% CI = 0.92-1.04, p = 0.41; I2 = 0%). CONCLUSIONS Combined inhibition therapy was superior to placebo and single EGFR inhibition in terms of ORR, PFS for advanced NSCLC, however, no statistical difference were found in term of OS. Besides, combined inhibition therapy was not superior to single VEGF inhibition in terms of ORR, PFS and OS. Therefore, combined inhibition therapy is recommended to treat advanced NSCLC patients.