Emulation of the FLAURA (NCT02296125) Trial Using Specialty Oncology Electronic Health Records Databases

Market availability of osimertinib began April 18, 2018. Study Period: ENCORE database 1 (EDB1): Patient identification period: 01/01/2011-04/30/2024 with follow-up information through data cut-off date on 04/30/2024 ENCORE database 2 (EDB2): Follow-up information through 02/24/2023 (there is no specific time period restrictions for patient eligibility) ENCORE database 4 (EDB4): Patient identification period: 10/01/2018-09/30/2023 with follow-up information through data cut-off date on 09/30/2023. Inclusion Criteria: * Age \>= 18 * New users of first-line antineoplastic system therapy: osimertinib, gefitinib, or erlotinib for advanced/metastatic disease * Mention of 'adenocarcinoma' histology ('non-squamous' in EDB1) * Line of therapy setting needs to be 'advanced' (EDB1), 'metastatic' (EDB2) or there needs to be evidence of metastatic disease at time of treatment initiation (EDB4) * Evidence of any EGFR mutation in the 180 days before/on treatment initiation * Treatment needs to be first-line for advanced (EDB1) or metastatic (EDB2) disease or patients with prior exposure to any potential antineoplastic treatment commonly used in the advanced/metastatic NSCLC setting are excluded (EDB4) * ECOG 0 or 1 in the 90 days before/on treatment initiation Exclusion Criteria: * Missing age * Concurrent primary malignancies (EDB2) * Missing date of diagnosis or clinician note in the EHR (EDB2) * Only one visit at provider site (EDB2) * Metastatic (includes leukemias and multiple myeloma) for a malignancy diagnosed prior to the malignancy of interest with the presence of low grade (inclusive of grades 1 and 2) neuroendocrine histology (EDB2) * Participation in any clinical trial at any point in treatment history (EDB4)