RecruitingPhase 2Drug trialA Study of Osimertinib-based Adaptive Treatment Guided by ctDNA EGFRm+ Monitoring in NSCLCThe goal of this adaptive, interventional study is to assess the efficacy and safety of osimertinib-based adaptive treatment based on ctDNA dynamic monitoring in locally advanced or metastatic EGFRm NSCLC participants with ctDNA EGFRm clearance after osimertinib plus chemotherapy. The main questions it aims to answer are: 1) PFS during adaptive treatment period in Cohort 1 defined as from initiation of Osimertinib in adaptive period to progression per investigator assessment; 2) Time from initiation of osimertinib in adaptive period to first ctDNA EGFRm relapse or death