Targeting exon mutations in NSCLC: clinical insights into LAG-3, TIM-3 pathways, and advances in fourth-generation EGFR-TKIs.

Abstract

Lung cancer remains the second leading cause of cancer-related morbidity and mortality worldwide, with non-small cell lung cancer (NSCLC) accounting for the majority of cases. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have become the standard first-line therapy for advanced NSCLC with EGFR mutations, offering significant improvements in progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) compared to chemotherapy alone. Recent studies suggest that their effectiveness decreased with the emergence of acquired resistance, such as C797S and T790M. Immunotherapy alone also shows enhanced PFS and OS over chemotherapy; however, its applicability can be limited in cases with low programmed cell death ligand 1 (PD-L1) expression and result in immune-related adverse effects like those observed in retrospective, non-randomized studies. Emerging fourth-generation EGFR-TKIs, currently under clinical trials, show promising potential to address these resistance mechanisms. Advanced inhibitors, including BBT-176, BLU-945, and BLU-701, have effectively targeted resistant mutations and reduced disease progression. Studies have suggested that combining fourth-generation EGFR-TKIs with immunotherapies targeting novel pathways like LAG-3 and TIM-3 may enhance patient outcomes. Such combination regimens aim to optimize PFS, OS, and ORR while minimizing adverse effects and addressing the limitations of current therapies. This study explores the landscape of EGFR mutations, their clinical significance, and the integration of innovative fourth-generation EGFR-TKIs with immunotherapies, emphasizing the potential of precision medicine in advancing the management of EGFR-mutated NSCLC.