Treatment Patterns by EGFR Mutation Status in Non-Small Cell Lung Cancer Patients in the USA: A Retrospective Database Analysis.

INTRODUCTION: Targeted therapies, including tyrosine kinase inhibitors (TKIs) that target the sensitizing epidermal growth factor receptor (EGFR) gene are recommended for patients with non-small cell lung cancer (NSCLC). Most patients with NSCLC who test positive for the EGFR mutation and receive TKIs develop resistance to these drugs. Questions remain regarding which treatment sequence is optimal for patients with EGFR-mutant NSCLC, and few studies have evaluated patterns of TKI treatment use in NSCLC, irrespective of EGFR mutation status, in a real-world setting. This population-based study aimed to evaluate treatment patterns at a national level in the USA. METHODS: This retrospective observational study used data from the US Oncology Network's iKnowMed database. Patients with advanced NSCLC who initiated first-line therapy with erlotinib and/or intravenous chemotherapy between January 1, 2012 and June 30, 2015 and met all other study criteria were included. Descriptive analyses assessed demographic and clinical characteristics and treatment patterns among the overall study cohort, as well as for specific erlotinib treatment subgroups, stratified by EGFR status. RESULTS: Among the 3108 patients identified, 18.5% were EGFR positive, 49.8% were EGFR negative, and 31.7% were EGFR documented unknown. For the overall cohort, 18.4% received first-line erlotinib monotherapy, fewer than 1% received first-line combination therapy (erlotinib plus chemotherapy), 4.7% received second-line erlotinib monotherapy, and 3.3% received second-line combination therapy. First-line erlotinib monotherapy was used in 77.8% of all EGFR positive patients. Almost two-thirds of the overall cohort were not observed to have advanced to second-line therapy. CONCLUSIONS: As treatment options evolve, this study provides real-world treatment patterns that suggest concordance with NCCN guidelines and confirm the remaining need to understand sequencing of therapies and related outcomes. FUNDING: Eli Lilly and Company.