A Study of BL-ARC002 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 restrictions; 3. Age: ≥18 and ≤75 years (Phase Ia); ≥18 years (Phase Ib); 4. Expected survival time ≥3 months; 5. Histopathologically and/or cytologically confirmed locally advanced or metastatic solid tumors that have failed standard treatment; 6. Agree to provide archived tumor tissue specimens or fresh tissue samples from the primary or metastatic lesions within the past 2 years; 7. Must have at least one measurable lesion as defined by RECIST v1.1; 8. Eastern Cooperative Oncology Group performance status of 0 or 1; 9. Toxicities from prior anti-tumor therapy must have recovered to ≤ Grade 1 as defined by NCI-CTCAE v5.0; 10. No severe cardiac dysfunction, with left ventricular ejection fraction ≥50%; 11. Organ function levels must meet the required criteria; 12. Coagulation function: International normalized ratio ≤1.5 and activated partial thromboplastin time ≤1.5 × upper limit of normal; 13. Urine protein ≤2+ or ≤1000 mg/24 hours; 14. For premenopausal women of childbearing potential, a pregnancy test must be performed within 7 days before starting treatment, with serum pregnancy test being negative, and they must not be breastfeeding; all enrolled patients (regardless of sex) must practice adequate barrier contraception throughout the entire treatment period and for 6 months after treatment completion. Exclusion Criteria: 1. Use of chemotherapy, biotherapy, immunotherapy, etc., within 4 weeks or 5 half-lives prior to the first dose; 2. History of serious heart disease; 3. QT interval prolongation, complete left bundle branch block, or third-degree atrioventricular block; 4. Active autoimmune diseases and inflammatory diseases; 5. Diagnosis of another malignancy within 5 years prior to the first dose; 6. Hypertension inadequately controlled by two antihypertensive medications; 7. History of ILD requiring steroid therapy, current ILD, or ≥ Grade 2 radiation pneumonitis; 8. Active symptoms of central nervous system metastasis; 9. History of allergy to recombinant humanized or human-mouse chimeric antibodies, or allergy to any excipient component of BL-ARC002; 10. Prior organ transplantation or allogeneic hematopoietic stem cell transplantation; 11. Cumulative anthracycline dose \> 360 mg/m² from prior (neo)adjuvant anthracycline-based therapy; 12. Positive for human immunodeficiency virus antibody, active tuberculosis, active hepatitis B virus infection, or active hepatitis C virus infection; 13. Active infection requiring systemic therapy; 14. Participation in another clinical trial within 4 weeks prior to the first dose; 15. Pregnancy or breastfeeding; 16. Study participants with claustrophobia or any condition preventing them from lying still to complete examinations; 17. Other conditions deemed by the investigator to make the participant unsuitable for this clinical trial.