Treatment outcomes of non-small cell lung cancers treated with EGFR tyrosine kinase inhibitors: a real-world cohort study

BackgroundEpidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) are a standard of care treatment options in non-small cell lung cancer (NSCLC). The present study investigated real-world EGFR TKI use and patient outcomes in NSCLC.Material and methodsWe collected all the patients who had reimbursement for EGFR TKIs in Finland 2011-2020 and had data available at Finnish Cancer Registry. Survival and time-on-treatment (ToT) were analyzed from the first EGFR TKI purchase and patients were stratified according to the TKIs.ResultsWhole patient cohort consisted of 1498 individuals who were treated with erlotinib (n = 998), afatinib (n = 258), or gefitinib (n = 238). In the EGFR mutant cohort (all gefitinib users and afatinib users with non-squamous histology; n = 466), survival was comparable to registrational trials while patients treated with afatinib had improved survival (HR 0.67 CI 95% 0.53-0.85) and longer ToT (13.9 vs 11.9 months, NS) compared to those treated with gefitinib. Females treated with afatinib had improved survival (HR 0.61 CI 95% 0.44-0.83) and longer ToT (15.1 vs 12.5 months, NS) compared to gefitinib while similar was not observed in males. Later line osimertinib treatment was applied for 78 patients. Approximately 20% of the individuals treated with previous gefitinib or afatinib had later line osimertinib treatment. Efficacy analysis of osimertinib treated showed similar ToT and survival regardless of the first line EGFR TKI.ConclusionsEGFR mutants treated with afatinib have improved outcomes compared to gefitinib while later-line osimertinib was applied only for around 20% of the individuals. The study further highlights the good real-world performance of EGFR TKIs and sheds light on therapy sequencing.