Furmonertinib 160mg vs 80mg + Chemotherapy in EGFR-Mutated NSCLC With Brain Metastases: Efficacy and Safety Study

IInclusion Criteria * Aged 18 to 75 years (male or female) * Histopathologically confirmed, unresectable, and non-radiocurable newly -diagnosed locally advanced or metastatic lung adenocarcinoma * Confirmed by local laboratory to have one of the following EGFR mutations: -19Del or L858R (single or mixed mutations are allowed) * Treatment-naive for locally advanced (not suitable for surgery/radiotherapy per investigator) or metastatic NSCLC; adjuvant/neoadjuvant therapy completed \>6 months before first progression is allowed (≤6 months is considered pretreated) * At least one measurable tumor lesion per RECIST 1.1 (lesions previously treated with radiotherapy are excluded; if only one measurable lesion exists, biopsy is allowed but baseline imaging must be performed ≥14 days after biopsy) * Confirmed stable and asymptomatic brain metastases * Sufficient organ function (per laboratory tests): ANC ≥1.5×10⁹/L, PLT ≥100×10⁹/L, HGB ≥90g/L; TBIL ≤1.5×ULN, AST/ALT ≤2.5×ULN (for liver metastasis: TBIL ≤3×ULN, AST/ALT ≤5×ULN); CrCL ≥50 ml/min (Cockcroft-Gault formula) * ECOG performance status 0-2 (no significant disease deterioration in 2 weeks before screening) * Expected survival \>12 weeks after first dose * Non-pregnant women of childbearing potential (no pregnancy plan); women and men agree to use effective contraception during the study and 6 months after drug discontinuation * Voluntarily signs informed consent and understands the study procedures Exclusion Criteria（排除标准） * NSCLC with predominantly squamous cell histology, small cell lung cancer, neuroendocrine carcinoma, or other non-adenocarcinoma histologies * Concurrent positive for other driver genes (ALK fusion, ROS1 fusion, RET rearrangement, BRAF mutation, NTRK fusion, MET mutation, KRAS mutation); TP53, RB1, and BRAC mutations are excluded * Expected to receive other anti-tumor therapies during the trial * Major surgery (except vascular access or biopsy) within 4 weeks before first dose or planned during the trial * Use of CYP3A4 strong inhibitor within 7 days or strong inducer within 21 days before first dose; use of anti-tumor Chinese medicine within 2 weeks before first dose or planned during the trial * Participation in other clinical trials (investigational drug/device) within 4 weeks or 5 half-lives before first dose * Use of other anti-tumor drugs within 14 days before first dose * Spinal cord compression or symptomatic leptomeningeal metastasis * Toxicity from previous anti-tumor therapy not recovered to ≤CTCAE Grade 1 (except alopecia or platinum-induced peripheral neuropathy) * Symptomatic or unstable pleural/peritoneal effusion (stable ≥14 days after drainage is allowed) * History of other malignancies (except cured malignancies with no recurrence in 5 years: cervical carcinoma in situ, basal cell carcinoma, papillary thyroid carcinoma) * History of interstitial lung disease (ILD), drug-induced ILD, steroid-requiring radiation pneumonitis, or suspected ILD * Uncontrolled severe systemic diseases (e.g., hypertension, diabetes, NYHA III-IV heart failure, unstable angina, myocardial infarction within 1 year, active bleeding) * QTc \>470 msec on resting ECG * Clinically significant QT prolongation or arrhythmias increasing QT risk (e.g., complete left bundle branch block, III° AV block, congenital long QT syndrome, severe hypokalemia, use of drugs causing QT prolongation) * Severe gastrointestinal dysfunction that impairs drug intake or absorption Infections requiring intravenous medication * Active mental illness or drug addiction * Known or suspected allergy to furmonertinib or its components * Pregnant or lactating women; women or their partners planning pregnancy during the study * Poor compliance (unable to follow study procedures) * Other conditions deemed unsuitable for enrollment by the investigator