Ivonescimab Combined With Chemotherapy for the Treatment of Leptomeningeal Metastases Failed to EGFR-TKIs

Research objective Main purpose Exploring the real-world effectiveness of Ivonescimab combined with chemotherapy for EGFR mutant NSCLC with leptomeningeal metastasis after EGFR-TKIs resistance. Outcome measure: Real world intracranial disease-free survival time (iPFS). Secondary purpose Federation patterns: describing different treatment modes in the real world; Outcome measures: Combination chemotherapy regimen and duration of chemotherapy. Efficacy: Further explore the effectiveness of Ivonescimab combined with chemotherapy for EGFR mutant NSCLC with leptomeningeal metastasis failed with EGFR-TKI treatment; Outcome measures: Objective response rate (LM-ORR), duration of intracranial response (iDoR), overall progression free survival (PFS), overall survival (OS), improvement in neurological function, CSF response rate based on CSF cytology. Safety: Explore the safety of Ivonescimab combined with chemotherapy for NSCLC patients with leptomeningeal metastases who have failed EGFR-TKI treatment; Outcome measures: incidence of adverse events (TEAEs), laboratory test outliers, and serious adverse events (SAEs). Research endpoint Primary endpoint * iPFS (intracranial progression free survival). Secondary endpoint * Efficacy: leptomeningeal ORR (LM-ORR), intracranial duration of response (iDoR), overall progression free survival (PFS), overall survival (OS), improvement in neurological function, and CSF response rate based on CSF cytology; * Safety: Determine the incidence and severity of adverse events (AE) and serious adverse events (SAE) according to NCI-CTCAE5.0 standards; Changes in vital signs, laboratory abnormalities, and quality of life scores. Exploratory endpoint: efficacy related biomarkers