Study of patient characteristics, treatment patterns, EGFR testing patterns and outcomes in real-world patients with EGFR m + non-small cell lung cancer.

Objective: This retrospective, observational study examined patient characteristics, treatment patterns, testing patterns, and outcomes of US patients receiving first-/second- or third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs).
Methods: This study used an electronic health record-derived de-identified database. Eligible patients had advanced EGFR m ⁺ non-small cell lung cancer. Descriptive statistics were used to describe demographic, clinical, and treatment characteristics. Logistic regression models were used to identify patient characteristics that were associated with the use of osimertinib vs. a first-/second-generation EGFR TKI. Kaplan-Meier methods were used for survival analysis.
Results: Of the 782 patients who received first-line (1L) therapy with first-/second-generation EGFR TKIs in cohort A, erlotinib was the most common (58%), and osimertinib was the most widely prescribed second-line (2L) therapy (52%). Of the patients who received 1L therapy with osimertinib, a greater range of treatments were prescribed in 2L. A third of patients treated with first-/second-generation EGFR TKIs underwent EGFR testing near the end of 1L, and 44% of these patients had T790M positive disease. The median time on targeted therapy (TTT) of the cohort was 11.1 months (95% confidence interval [CI] 9.7, 12.3), and the median overall survival from the start of 1L therapy was 23.5 months (95% CI 20.7, 24.8).
Conclusions: The majority of patients treated with first-/second-generation EGFR TKIs went on to receive osimertinib in the 2L setting, but overall, only a third of patients had received molecular testing at progression. Improved testing frequency is vital to inform treatment decisions.