Erlotinib in EGFR TKI-progressed lung cancer: Retrospective real-world insights from a tertiary cancer center in South India

ABSTRACT Background: Osimertinib benefits patients with non-small cell lung cancer (NSCLC), progressing on first-line epidermal growth factor receptor ( EGFR ) tyrosine-kinase-inhibitors (TKIs), but high cost restricts access in low- and middle-income countries (LMICs). We evaluated erlotinib rechallenge in this setting. Objectives: Primary objectives were to assess event-free survival (EFS) and overall survival (OS). Secondary objective was disease control rate (DCR) of erlotinib in EGFR -mutated metastatic NSCLC post- EGFR -TKIs. Materials and Methods: This retrospective study (2011–2024) at Cancer Institute, WIA, Chennai included patients with metastatic NSCLC and EGFR mutations progressed on prior TKIs and received erlotinib. Patients without EGFR mutations or with erlotinib exposure