Real-Life Efficacy of Osimertinib in Pretreated Octogenarian Patients with T790M-Mutated Advanced Non-small Cell Lung Cancer.

<bold>Background: </bold>The resistance mutation T790M is reported in 50-60% of patients pretreated with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). Osimertinib has been approved in these patients, but data in octogenarians remain rare.<bold>Objective: </bold>The objective of this retrospective analysis was to evaluate in real life the efficacy of osimertinib in a population of octogenarian patients.<bold>Methods: </bold>This retrospective multicentric study included pretreated octogenarian patients with EGFR T790M-mutated advanced non-small cell lung cancer (NSCLC) in the setting of the French early access program for osimertinib. The primary endpoints were progression-free survival (PFS) and overall survival (OS) from osimertinib initiation.<bold>Results: </bold>In total, 43 patients were included (mean age 84.6 years; women 90.7%: adenocarcinoma 100%; never smokers 90.5%; at osimertinib initiation: performance status ≥ 2, 42.4%; stage 4, 93.0%; brain metastases 16.3%). Patients received a median of two lines of treatment before osimertinib initiation, and all received first- or second-generation EGFR TKIs before osimertinib (first line in 79.1%). Osimertinib was used as a second-line treatment in 41.9% of cases and third line or more in 58.1%. Median PFS was 17.5 (95% confidence interval [CI] 12.2-19.0) months for the entire population: 20.6 (95% CI 18.8-not reached) months in patients with brain metastases and 16.7 (95% CI 10.4-18.9) months in patients without (p = 0.1). There was no significant difference for osimertinib treatment as second or third line or more (17.1 vs. 18.6 months, respectively). OS was 22.8 (95% CI 15.7-not reached) months from osimertinib initiation.<bold>Conclusion: </bold>The efficacy of osimertinib as second-line treatment or more in octogenarian pretreated patients with EGFR T790M-mutated advanced NSCLC in a real-life setting was similar to that in randomized controlled trials. [ABSTRACT FROM AUTHOR]