Gumarontinib Combined With 3rd EGFR-TKI in Patients With Non-small Cell Lung Cancer.

Inclusion Criteria: * ≥18 years old. * Locally advanced or metastatic (stage IIIB-IV) NSCLC confirmed histologically or cytologically, stage III patients are unresectable and are not suitable for radical concurrent chemoradiotherapy. * ECOG 0\~1. * Expected survival time ≥3 months * Patients with EGFR mutations known to be associated with drug sensitivity (i.e., exon 19 deletion or L858R mutation). * For advanced NSCLC, 2 or 3 generations of EGFR-TKI or EGFR-TKI (EGFR-TKI monotherapy, combination chemotherapy or bevacizumab are acceptable) have been treated with treatment failure, and EGFR-TKI has only been received as first-line therapy: Cohort 1: Third-generation EGFR-TKI therapy failed (EGFR-TKI monotherapy, combination chemotherapy, or bevacizumab could be used) without first - or second-generation EGFR-TKI therapy; Cohort 2: EGFR-TKI therapy failed in the first or second generation (EGFR-TKI monotherapy, combination chemotherapy, or bevacizumab were acceptable), and the status of T790M was not limited without the third generation of EGFR-TKI therapy or the first three generations of EGFR-TKI therapy \< 4 weeks (28 days); * Met the following criteria for EGFR-TKI treatment failure (acquired resistance): Continuous treatment with EGFR-TKI in the past; Treatment with EGFR-TKI resulted in any of the following objective clinical benefits (RECIST 1.1) ; Documented partial or complete remission; Clinical benefit for ≥6 months; Imaging disease progression during EGFR-TKI treatm…