RecruitingPhase 2Drug trialHigh-dose Furmonertinib in the Treatment in Patients With Advanced, Metastatic NSCLC With Progressed After First- or Second-line Treatment With OsimertinibThis is a prospective, randomised, uncontrolled phase II clinical trial planned to include 84 subjects with metastatic lung adenocarcinoma that had progressed after first- or second-line treatment with Osmertinib, who were randomly assigned to trial group 1 and trial group 2, and were given Furmonertinib 160 mg and 240 mg once/day, orally, respectively, with efficacy evaluated every 6 weeks until disease progression, intolerable toxic side effects, or Subjects voluntarily withdrew informed consent.