A Study of SI-B036 in Patients With Locally Advanced or Metastatic Solid Tumors

Inclusion Criteria: 1. Voluntarily sign the informed consent form and comply with the protocol requirements; 2. No gender restriction; 3. Age: ≥18 years and ≤75 years; 4. Expected survival time ≥3 months; 5. Locally advanced or metastatic solid tumors; 6. Agree to provide archived tumor tissue specimens from primary or metastatic lesions within 2 years or fresh tissue samples; 7. Must have at least one measurable lesion as defined by RECIST v1.1; 8. ECOG performance status score of 0 or 1; 9. Toxicity from prior anti-tumor therapy has recovered to ≤ Grade 1 as defined by NCI-CTCAE v6.0; 10. No severe cardiac dysfunction, left ventricular ejection fraction ≥50%; 11. Organ function levels must meet the requirements; 12. Coagulation function: International Normalized Ratio ≤1.5, and Activated Partial Thromboplastin Time ≤1.5 × ULN; 13. Urine protein ≤2+ or ≤1000 mg/24h; 14. For premenopausal women of childbearing potential, a pregnancy test must be performed within 7 days before starting treatment, serum pregnancy must be negative, and they must be non-lactating; all enrolled patients (regardless of male or female) must adopt adequate barrier contraceptive measures throughout the entire treatment period and for 6 months after treatment completion; 15. The trial participant is capable and willing to adhere to the visit schedule, treatment plan, laboratory tests, and other study-related procedures specified in the protocol. Exclusion Criteria: 1. Use of chemotherapy, biological therapy, immunotherapy, etc. within 4 weeks or 5 half-lives prior to the first dose; 2. Receipt of immunosuppressive therapy within 2 weeks prior to the first dose; 3. History of severe cardiac or cerebrovascular disease; 4. QT interval prolongation, complete left bundle branch block, etc.; 5. Active autoimmune diseases and inflammatory diseases; 6. Prior experience of ≥ grade 3 toxicity related to anti-angiogenic therapy during previous anti-angiogenic treatment; 7. Diagnosis of another solid tumor within 5 years prior to the first dose; 8. Unstable thrombotic event requiring therapeutic intervention within 6 months prior to the first dose; 9. Poorly controlled hypertension; 10. Diabetic patients with poorly controlled blood glucose; 11. History of ILD requiring steroid therapy, or current ILD, or ≥ grade 2 radiation pneumonitis; 12. Concomitant pulmonary disease causing severe respiratory impairment; 13. Active central nervous system metastases; 14. History of allergy to recombinant humanized or human-mouse chimeric antibodies, or hypersensitivity to any excipient component of SI-B036; 15. Prior organ transplantation or allogeneic hematopoietic stem cell transplantation; 16. Positive for human immunodeficiency virus antibody, active tuberculosis, active hepatitis B virus infection, or active hepatitis C virus infection; 17. Active infection requiring systemic therapy within 4 weeks prior to the first dose of study drug; 18. Presence of pleural, abdominal, or pericardial effusion requiring drainage and/or accompanied by symptoms within 4 weeks prior to the first dose of study drug; 19. Imaging findings indicating tumor invasion or encasement of major thoracic blood vessels, pericardium, or heart; 20. Study participants with clinically significant bleeding or a clear bleeding tendency within 4 weeks prior to screening; 21. History of fistula, gastrointestinal perforation, or intra-abdominal abscess within 6 months prior to the first dose; 22. Use of another investigational drug within 4 weeks or 5 half-lives prior to the first dose; 23. Pregnant or breastfeeding women; 24. Other conditions deemed by the investigator to make the participant unsuitable for enrollment in this clinical trial.