A I/II Phase Clinical Study to Evaluate the Safety and Efficacy of RC288 in the Treatment of Solid Tumors

Inclusion Criteria: 1. Voluntarily participate in this study, sign the informed consent form, and be able to adhere to the study protocol; 2. Age between 18 and 75 years (including 18 and 75 years); 3. ECOG PS score of 0 or 1; 4. Expected survival ≥12 weeks; 5. According to RECIST v1.1 criteria, based on imaging examinations, there is at least one measurable target lesion; 6. Sufficient bone marrow, liver, kidney, and blood clotting function Exclusion Criteria: 1. Pregnant, breastfeeding, or intending to become pregnant subjects. 2. Subjects with brain metastases. 3. Subjects with unresolved toxicities from prior anti-tumor therapy not recovered to NCI-CTCAE v6.0 Grade 1. 4. Subjects with known hypersensitivity or delayed allergic reactions to any component of the investigational drug or similar drugs. 5. Subjects with acute, chronic, or symptomatic infections. 6. Subjects with uncontrolled cardiovascular diseases. 7. Subjects with confirmed or suspected interstitial lung disease (ILD), drug-related pneumonia, radiation pneumonitis, severely impaired pulmonary function, or other pulmonary diseases. 8. History of underlying pulmonary disease. 9. Subjects with a history of cirrhosis (Child-Pugh B or C class). 10. Clinically significant gastrointestinal disease. 11. Subjects with uncontrolled diabetes (HbA1c ≥ 10%). 12. Occurrence of hemorrhagic events of Grade ≥2 per NCI CTCAE (v6.0) within 4 weeks prior to screening; or clinical manifestations suggestive of a significant bleeding tendency within 4 weeks prior to screening. 13. Imaging during the screening period shows tumor invasion or involvement of vital organs, with imaging evidence judged by the investigator to indicate a risk of bleeding or fistula formation. 14. History of arterial/venous thromboembolic events within 6 months prior to the first dose. 15. Presence of pericardial effusion or cardiac tamponade, or third-space fluid accumulation that, in the investigator's judgment, cannot be stably controlled by drainage or other methods. 16. History of active autoimmune disease requiring systemic therapy within the past 2 years. 17. History of other invasive malignancies within 5 years prior to the first dose, or evidence of residual disease from any previously diagnosed malignancy. 18. History of other acquired or congenital immunodeficiency diseases, or history of organ transplantation. 19. History of or current poorly controlled psychiatric disorder. 20. Poor compliance, and patients who are expected to be unable to cooperate with the completion of trial procedures. 21. Presence of any other disease, metabolic abnormality, physical examination finding, or laboratory abnormality that, in the investigator's judgment, gives reasonable suspicion of a condition that contraindicates the use of the investigational drug, may affect the interpretation of study results, or places the patient at high risk. 22. Local or systemic diseases not caused by malignancy, or diseases or symptoms secondary to the tumor, which may lead to higher medical risks and/or uncertainty in survival assessment.