This randomized, open label Phase IV trial will be performed in patients with a diagnosis of advanced NSCLC (non-squamous cell histology), harboring EGFR mutation positive but T790M Mutation negative, who have no previous chemotherapy for metastatic NSCLC. Neoadjuvant or adjuvant systemic treatments had to be finished at least (≥) 6 months before study inclusion. In conclusion, this study is investigating the important clinical question whether tumor growth and long term overall survival for a patient is better controlled in a specific treatment sequence of different EGFR-inhibitors. Patients will be treated with registered compounds according to their label in both treatment arms. Thus, all patients will get an effective treatment regimen and patients who progressed on afatinib, and who developed a T790M mutation will be treated subsequently with osimertinib. Those who progressed under osimertinib or under afatinib without T790M mutation will be treated according to the current treatment guidelines with Investigator´s choice of active therapy (ICT) including but not limited to platin doublet chemotherapy.
