Inclusion Criteria:
1. Signed informed consent and voluntarily enrolled in this study;
2. Histologically or cytologically confirmed extensive-stage small cell lung cancer;
3. Patients with other types of advanced solid tumors confirmed by histology or cytology; patients who, based on currently available data, the investigator believes may benefit from adebrelimab treatment may also be considered for enrollment;
4. Patients in Cohort 1 who experience disease progression and whose second-line treatment options, as assessed by the investigator, include adebrelimab in combination therapy may be enrolled in Cohort 2;
5. Age 18-80 years;
6. Patients deemed by the investigator to be eligible for adebrelimab monotherapy or combination therapy;
7. Female patients of childbearing potential must have a negative urine or serum pregnancy test within 7 days prior to the first dose of study drug (Cycle 1, Day 1). If the urine pregnancy test result cannot be confirmed as negative, a blood pregnancy test is required. Females and males of childbearing potential must agree to use appropriate contraceptive methods or undergo surgical sterilization during the trial and within 90 days after the last dose of the trial drug.
8. Ability to comply with study and follow-up procedures.
Exclusion Criteria:
1. Women who have been confirmed to be pregnant or breastfeeding;
2. Patients with histologically or cytologically confirmed central nervous system tumors, urinary system tumors, reproductive system tumors, bone tumors, soft tissue sarcomas, melanomas and other skin tumors;
3. Patients with a history of human immunodeficiency virus (HIV) infection (i.e. HIV 1/2 antibody positive);
4. Patients with known allergies to adebrelimab or any of its drugs and excipients;
5. Patients who are deemed by the investigator to be unsuitable for participation in this study in any other circumstances, including but not limited to the following: (1) Patients with autoimmune diseases (AIDs), especially neurological AIDs, or AIDs that are moderate to severe or in active stage and cannot be controlled by immunosuppressants or require high-dose immunosuppressants to control symptoms; (2) Patients with tuberculosis infection, active tuberculosis, and suspected active TB should be examined by chest X-ray, sputum, and clinical symptoms and signs to exclude; (3) The patient has previously received or is about to receive solid organ transplantation or hematopoietic stem cell transplantation; (4) The patient needs to use large doses of antibiotics, glucocorticoids, proton pump inhibitors and other drugs for a long time.
