This is a Phase I/II, Open Label Study of WSD0922-FU in Combination with Osimertinib for Patients with Locally Advanced or Metastatic Non-Small Cell Lung Cancer whose disease has progressed with third-generation EGFR-TKI with C797S mutation or is newly diagnosed with CNS metastasis with EGFR Del19 or L858R mutation

WSD0922-FU is a potent reversible inhibitor of both the single EGFRm+ and dual EGFRm+/C797S+ receptor forms of EGFR with selectivity margin over wild-type EGFR. This study aims to explore the safety, tolerability, pharmacokinetic characteristics and efficacy of WSD0922-FU combined with Osimertinib in patients with non-small cell lung cancer (NSCLC) with C797S mutation after first-line third-generation EGFR-TKI resistance, and then further confirm the safety and efficacy for newly diagnosed NSCLC BM patients with classical EGFR Del19 or L858R mutation

Inclusion Criteria:

• ≥Age 18, gender is not limited;
• Locally advanced or metastatic NSCLC confirmed by pathology;
• Patients who have been genetically tested to carry EGFR sensitive mutations;
• Blood/Tissue samples must be provided for testing;
• Must have a minimum life expectancy of >= 3 months;
• At least one measurable tumor lesion according to RECIST version 1.1; ● Previous radiotherapy-treated lesions cannot be used as target lesions unless imaging studies show clear progression of the lesions.
• Physical Status (ECOG PS) score was 0-1;
• Have full organ function;
• Eligible patients (male and female) who are fertile must agree to use a reliable contraceptive method ;
• Subjects are required to give informed consent to this study before the experiment and sign a written informed consent voluntarily.

Exclusion Criteria:

• Received chemotherapy, radiotherapy, biological therapy, targeted therapy, endocrine therapy, immunotherapy, or other anti-tumor drug treatments within 4 weeks before the first administration of the study drug.
• Have previously received more than two EGFR-TKI inhibitors for part A;
• Received major organ surgery (excluding puncture biopsy) or significant trauma within 4 weeks before the first administration, or require elective surgery during the trial period.
• Used strong CYP3A4 inhibitors or strong CYP3A4 inducers within 7 days before the first use of the study drugs.
• Adverse reactions from previous anti-tumor treatments have not recovered to NCI-CTCAE v5.0 grade ≤1 (except for toxicities judged by the researcher to have no safety risks, such as hair loss, grade 2 peripheral neurotoxicity, and stable thyroid function after hormone replacement therapy).
• Skin/pressure ulcers, chronic leg ulcers, known active gastric ulcers, or non-healing wounds.
• History of severe allergies, or allergies to any active or inactive ingredients of the study drug;
• Severe infections requiring intravenous antibiotic infusion or hospitalization at the time of screening; or uncontrollable active infections within 4 weeks before administration;
• Known active or suspected autoimmune diseases; or known active ocular diseases (such as active wet age-related macular degeneration, diabetic retinopathy with macular edema);
• Human immunodeficiency virus (HIV) (HIV1/2 antibody) positive, syphilis spirochete antibody positive .
• Patients with interstitial lung disease.
• History of severe cardiovascular diseases.
• Unable to orally swallow medication, or there is a condition that significantly affects gastrointestinal absorption as judged by the researcher; Clinical intervention is required for pleural effusion, ascites (excluding subjects who do not need drainage and have been stable for more than 2 weeks after drainage).
• Known alcohol or drug dependence.
• Mental disorders or poor compliance;
• Pregnant or lactating women;
• The investigator believes that the subject has other reasons that make them unsuitable for participating in this clinical study.