Small Cell Lung Cancer (SCLC) Clinical Trials

• Able to provide a signed and dated informed consent form, including compliance with the requirements and restrictions listed in the ICF and this protocol;

• Subjects are ≥ 18 years old when signing the ICF;

• Subjects have an ECOG performance status score of 0 or 1 and have not deteriorated in the past 2 weeks;

• Life expectancy ≥ 3 months;

• Histologically or cytologically confirmed ES-SCLC (stage IV \[any T stage, any N stage, M1 a/b/c stage\] according to the 8th edition of the AJCC TNM staging system for lung cancer, or T3-4 stage disease caused by multiple lung nodules and the disease is too diffuse, or the tumor/nodule volume is too large to be tolerated by a tolerable radiotherapy plan);

• The presence of at least one measurable lesion (based on RECIST 1.1): with a long diameter ≥ 10 mm (lymph node lesions require a short diameter of ≥15 mm) that can be accurately and repeatedly measured at baseline under CT or MRI; and there are measurable lesions outside the central nervous system;

• SCLC patients who have not received any systemic anti-tumor treatment for advanced disease; if the patient has received neoadjuvant/adjuvant therapy in the past, the interval between the diagnosis of ES-SCLC and the completion of the last treatment must be at least 6 months;

• Patients must be suitable for platinum (cisplatin or carboplatin)-based chemotherapy as the first-line treatment for ES-SCLC;

• Adequate bone marrow reserve and organ system function reserve, summarized as follows:

‣ Absolute neutrophil count (ANC) ≥ 1.5×109/L without growth factor support;

⁃ Platelet ≥ 100×109/L without growth factor support or blood transfusion;

⁃ Hemoglobin ≥ 9 g/dL or 90 g/L without erythropoietin or blood transfusion;

⁃ Total bilirubin ≤ 1.5 × ULN; if suffering from Gilbert syndrome (unconjugated hyperbilirubinemia), total bilirubin should be ≤ 3 × ULN;

⁃ ALT and AST ≤ 2.5 × ULN. For patients with documented liver metastases, AST and ALT levels ≤ 5 × ULN;

⁃ Creatinine clearance calculated by the Cockcroft-Gault method, \>60 ml/min for patients receiving cisplatin and \>45 ml/min for patients receiving carboplatin;

⁃ Urine routine examination shows less than 2+ protein in urine, or 24-hour urine protein quantitative \<1 g;

⁃ Good coagulation function, defined as international normalized ratio (INR) and/or prothrombin time (PT) ≤1.5 times ULN and/or activated partial thromboplastin time (APTT) ≤1.5 upper limit of normal; if the subject is receiving anticoagulant therapy, as long as the PT is within the intended use range of the anticoagulant drug;

⁃ Serum amylase ≤1.5 times ULN and/or serum lipase ≤1.5 times ULN;

⁃ Left ventricular ejection fraction (LVEF) ≥ 55%;

⁃ For patients with central nervous system metastases, the following conditions must be met before they can be included:

∙ No neurological symptoms or symptoms are stable for at least 2 weeks after local treatment, no need to use corticosteroids or anti-epileptic drugs, and hormonal treatment has been stopped within 3 days before the first dose of study drug;

‣ If brain metastases have been treated locally (radiotherapy or surgery), there should be a time window of ≥ 2 weeks before the first dose of study treatment to ensure that local treatment-related adverse events have been reduced to CTCAE ≤ 1 grade;

⁃ Women of childbearing potential must undergo a urine and/or serum pregnancy test (if the urine test cannot be confirmed as negative) within 7 days before the first medication, and the result must be negative; WOCBP or men and their WOCBP partners should agree to take effective contraceptive measures from the signing of the ICF until 6 months after the last dose of the study drug;

⁃ The subjects should be able to understand the study protocol and voluntarily comply with the study and follow-up;

⁃ For patients who are about to enter the maintenance period, the investigator shall determine whether they are suitable for starting treatment with golidocitinib combined with PD-1 inhibitors (generally all previous toxicities must be alleviated to CTCAE ≤ 1 level, excluding hair loss, fatigue or other conditions that are judged by the investigator to be clinically insignificant).