• aged 18 years or older (including 18 years) and up to 75 years (including 75 years)

• histologically confirmed NSCLC (by AJCC 8th edition lung cancer staging criteria)

• asymptomatic or minimally symptomatic brain metastases (i.e., headache, nausea, or seizures responding to dexamethasone/analgesic/antiepileptic agents at a stable drug dose for at least 3 days);

• brain metastases must meet the following criteria on diagnostic MRI: at least one lesion that can be classified as measurable disease according to RANO-BM, ≤ 10 brain or brainstem metastases

• epidermal growth factor receptor (EGFR) exon 19 deletion or exon 21 (L858R) substitution mutation (alone or in combination with other EGFR mutations);

• no prior systemic therapy other than neoadjuvant therapy, adjuvant therapy, or concurrent chemotherapy for more than 3 months prior to study entry

• Eastern Cooperative Oncology Organization Group (ECOG) physical status score of 0 or 1 and no worsening in the previous 2 weeks, with a minimum expected survival of 12 weeks.

• good hematopoietic function, defined as absolute neutrophil count ≥ 1.5 × 109 /L, platelet count ≥ 100 × 109 /L, and hemoglobin ≥ 90 g/L \[no transfusion or erythropoietin (EPO-dependent) within 7 days

• good coagulation, defined as an international normalized ratio (INR) or prothrombin time (PT) ≤ 1.5 times ULN; if the subject is on anticoagulation therapy, as long as the PT is within the proposed range of anticoagulant medication

⁃ good liver function, defined as a total bilirubin level ≤ 1.5 times the upper limit of normal (ULN); glutathione transaminase (AST) and glutamate transaminase (ALT) levels ≤ 2.5 times the ULN for patients without liver metastases; and AST and ALT levels ≤ 5 times the ULN for patients with documented liver metastases

⁃ good renal function, defined as serum creatinine ≤ 1.5 times ULN or calculated creatinine clearance ≥ 60 ml/min; urine protein less than 2+ on routine urine examination, or 24-hour urine protein quantification \< 1 g

⁃ Women of childbearing potential should have a negative urine or serum pregnancy test within 3 days prior to receiving the first dose of study drug (Week 1, Day 1).

⁃ male patients should be using barrier contraception (i.e., condoms) from screening until 6 months after discontinuation of study treatment

⁃ Subjects will voluntarily participate and sign an informed consent in writing.