Small Cell Lung Cancer (SCLC) Clinical Trials

• Age 18-75 years old, both male and female;

• Extensive small cell lung cancer (metastatic lesions ≤3 organs, ≤5 lesions) confirmed by histology or cytology (according to the Veterans Administration Lung Study Group (VALG staging), including asymptomatic brain metastasis, multiple lung metastases, supraclavicular or mediastinal lymph node metastasis, bone metastasis, adrenal metastasis, retroperitoneal lymph node metastasis, etc.;

• The score of ECOG physical condition is 0\

∙ 1;

• Never received first-line systemic therapy for ES-SCLC or immune checkpoint inhibitors before;

• Previous surgical treatment did not include adjuvant therapy such as radiotherapy and chemotherapy, and there was a five-treatment interval of at least 6 months from the diagnosis of extensive SCLC to the last chemotherapy and radiotherapy.

• It is necessary to be able to provide tumor tissue samples before the experimental treatment, which can be archived within 6 months before the first dose of the research drug or freshly obtained. Specimens should be fixed in formalin and embedded in paraffin (FFPE), and at least 10 4\

∙ 6μm thick sections can be cut out for staining and detection. Specimens that do not accept fine needle aspiration biopsy, cytological smears of pleural effusion drainage and centrifugation, bone lesions without soft tissue components or decalcified bone tumor specimens, and tissues drilled for biopsy are not enough for biomarker detection; Tissue samples should be submitted within 4 weeks before or after signing the notice, allowing research participants to provide Before the tumor tissue samples were taken into the study;

• Estimated survival time ≥8 weeks;

• There is a measurable lesion defined by RECIST standard v1.1: only when a previously irradiated lesion shows definite disease progression after radiotherapy and the previous lesion is not the only lesion can it be considered as a measurable lesion;

• Women of childbearing age must have a serum pregnancy study within 7 days before the first medication, and the result is negative. Participants in the study of women of childbearing age and male participants whose partners are women of childbearing age must agree to contraception within 24 weeks after signing the informed consent form to the last administration of the study drug;

• Before the first dose of study drug, the laboratory test value meets the following conditions:

‣ Blood routine (no blood transfusion and no use of hematopoietic stimulating factors within 14 days before screening) Material correction): White blood cell (WBC) ≥ 3.0× 10\^9/L; Absolute neutrophil count (ANC) ≥ 1.5× 10\^9/L; Platelet (PLT) ≥ 100× 10\^9/L； Hemoglobin (HGB) ≥ 9.0g/dl;

⁃ Liver function: aspartate aminotransferase (AST) ≤ 2.5 x ULN; Alanine aminotransferase (ALT) ≤ 2.5 x ULN, and ALT and AST≤5 x ULN； of participants in liver metastasis study; Total bilirubin (TBIL) ≤ 1.5 x ULN (except Gilbert syndrome ≤ 3.0 mg/dl);

⁃ Renal function: serum creatinine ≤1.5 x ULN or creatinine clearance rate (CRCL) ≥ 50 ml/minute;

⁃ Coagulation function: international normalized ratio (INR) ≤ 1.5 x ULN, activated partial thromboplastin time (APTT) ≤ 1.5 x ULN (only applicable to patients who have not received anticoagulant therapy at present, and patients who are currently receiving anticoagulant therapy should receive stable dose of anticoagulant therapy);

⁃ Others: lipase ≤1.5 x ULN (if lipase \> 1.5 x ULN without clinical or imaging confirmation of pancreatitis, you can be included in the group); Amylase ≤1.5 x ULN (if amylase \> 1.5 x ULN without clinical or imaging confirmation of pancreatitis, you can be included in the group); Alkaline phosphatase (ALP) ≤ 2.5 ULN, and ALP ≤ 5 ULN for participants in liver metastasis or bone metastasis research.

• The study participants voluntarily joined the study, signed the informed consent, and had good compliance and cooperated with the follow-up.