Armatinib Alone or in Combination With SRT for Brain Metastases EGFR-mutated Non-small Cell Lung Cancer

This trial is studying whether a targeted therapy drug called armatinib — used alone or combined with stereotactic radiation — works better for lung cancer that has spread to the brain. It focuses specifically on patients whose tumors have a specific genetic change called an EGFR mutation. **You may be eligible if:** - You are between 18 and 75 years old - You have non-small cell lung cancer (NSCLC) with an EGFR mutation (exon 19 deletion or exon 21 L858R) - Cancer has spread to the brain (up to 10 brain spots), but symptoms are mild or none - You have not received prior systemic therapy (other than short-term neoadjuvant/adjuvant treatment) - You are in good general health (ECOG score 0 or 1) - Your blood counts, liver, and kidney values are within normal ranges **You may NOT be eligible if:** - You have a different EGFR mutation or no EGFR mutation - Your brain metastases are causing severe symptoms not controlled by medication - You have more than 10 brain metastases - You have received prior EGFR-targeted therapy - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.