Real-world Outcomes, Treatment Patterns and T790M Testing Rates in Non-small Cell Lung Cancer Patients Treated with First-line First- or Second-generation Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors from the Slovenian Cohort of the REFLECT Study

BACKGROUND: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are effective treatments for EGFR mutation-positive (EGFRm) non-small cell lung cancer (NSCLC). However, routine clinical practice is different between countries/institutions. PATIENTS AND METHODS: The REFLECT study (NCT04031898) is a retrospective medical chart review that explored real-life treatment and outcomes of EGFRm NSCLC patients receiving first-line (1L) first-/second-generation (1G/2G) EGFR TKIs in 8 countries. This study included adult patients with documented advanced/metastatic EGFRm NSCLC with 1L 1G/2G EGFR TKIs initiated between Jan 2015 – Jun 2018. We reviewed data on clinical characteristics, treatments, EGFR/T790M testing patterns, and survival outcomes. Here, we report data from 120 medical charts in 3 study sites from Slovenia. RESULTS: The Slovenian cohort (median age 70 years, 74% females) received 37% erlotinib, 32% afatinib, 31% gefitinib. At the time of data collection, 94 (78%) discontinuations of 1L TKI, and 89 (74%) progression events on 1L treatment were reported. Among patients progressing on 1L, 73 (82%) were tested for T790M mutation yielding 50 (68%) positive results, and 62 (85%) received 2L treatment. 82% of patients received osimertinib. Attrition rate between 1L and 2L was 10%. The median (95% CI) real-world progression free survival on 1L EGFR TKIs was 15.6 (12.6, 19.2) months; median overall survival (95% CI) was 28.9 (25.0, 34.3) months. CONCLUSIONS: This real-world study provides valuable information about 1G/2G EGFR TKIs treatment outcomes and attrition rates in Slovenian EGFRm NSCLC patients. The reduced attrition rate and improved survival outcomes emphasize the importance of 1L treatment decision.