Efficacy analysis of immunotherapy‑based combinations for patients with EGFR‑mutant advanced non‑small cell lung cancer after TKI failure

Treatment options for epidermal growth factor receptor (EGFR)-mutant advanced non-small cell lung cancer (NSCLC) following tyrosine kinase inhibitor (TKI) failure are limited, and platinum-based chemotherapy remains the main treatment. The development of effective immunotherapy for this disease has been challenging. In the present study, 37 patients with EGFR-mutant advanced NSCLC who were treated with programmed cell death-1 (PD-1) inhibitor-based combinations after TKI failure were reviewed. The total cohort had a median progression-free survival (mPFS) of 5.2 months (95% CI, 4.077-6.323 months) and a median overall survival (mOS) of 18.3 months (95% CI, 12.932-23.668 months). Patients with Eastern Cooperative Oncology Group performance-status (ECOG-PS) scores of 0 or 1 had longer mPFS than those with ECOG-PS scores of 2 (5.4 vs. 2.4 months; P=0.006). In addition, a PFS benefit was observed in patients with EGFR T790M-negative compared with EGFR T790M-positive tumors (mPFS 6.2 vs. 4.4 months; P=0.041). Patients treated with immunotherapy-based combinations as a front-line therapy had a longer mPFS than those in which the combinations were used as a late-line therapy (6.2 vs. 2.4 months; P<0.001). PD-1 inhibitor combined with chemotherapy and bevacizumab did not show a clear advantage over PD-1 inhibitor combined with chemotherapy alone (mPFS, 6.2 vs. 4.4 months; P=0.681), although it resulted in an improved overall response rate (ORR) and disease control rate. Notably, the 7 patients with a programmed cell death ligand-1 (PD-L1) tumor proportion score of ≥50% had an ORR of 100% and an mPFS of 8.3 months. Therefore, it is suggested that PD-1 inhibitor-based combinations should be a priority treatment option in selective populations, such as those with low ECOG-PS scores, T790M-negative status or high PD-L1 expression in EGFR-mutant NSCLC after TKI failure. The use of immunotherapy and chemotherapy in combination with antiangiogenic agents appears to be a promising combination therapy for such patients.