Inclusion Criteria:
1. Voluntarily sign the informed consent form and agree to comply with the protocol requirements;
2. No gender restriction;
3. Age: ≥18 years and ≤75 years;
4. Expected survival time ≥3 months;
5. Recurrent or metastatic nasopharyngeal carcinoma and other solid tumors;
6. Agree to provide archived tumor tissue specimens or fresh tissue samples from the primary or metastatic lesions within 3 years;
7. Must have at least one measurable lesion as defined by RECIST v1.1;
8. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, with no deterioration within 2 weeks prior to the first dose;
9. Toxicity from prior anti-tumor therapy must have recovered to ≤ Grade 1 as defined by NCI-CTCAE v6.0;
10. No severe cardiac dysfunction, with left ventricular ejection fraction (LVEF) ≥50%;
11. Organ function levels must meet the required criteria;
12. Coagulation function: international normalized ratio (INR) ≤1.5, and activated partial thromboplastin time (aPTT) ≤1.5 × upper limit of normal (ULN);
13. Urine protein ≤1+ or ≤1000 mg/24h;
14. For premenopausal women of childbearing potential, a serum pregnancy test must be performed within 7 days prior to the start of treatment and must be negative, and they must be non-lactating; all enrolled patients (both male and female) must adopt adequate barrier contraceptive measures throughout the entire treatment period and for 6 months after the completion of treatment;
15. The trial participant must be capable of and willing to comply with the visit schedule, treatment plan, laboratory tests, and other study-related procedures specified in the protocol.
Exclusion Criteria:
1. Use of chemotherapy, biotherapy, immunotherapy, or other systemic anti-cancer therapies within 4 weeks or 5 half-lives prior to the first dose;
2. History of severe cardiac or cerebrovascular disease;
3. Prolonged QTc interval, complete left bundle branch block, third-degree atrioventricular block, or frequent and uncontrolled arrhythmias;
4. Active autoimmune diseases and inflammatory diseases;
5. Diagnosis of another primary malignancy within 5 years prior to the first dose;
6. Unstable thrombotic events requiring therapeutic intervention within 6 months prior to the first dose;
7. Hypertension inadequately controlled by antihypertensive medications;
8. Poorly controlled blood glucose (diabetes);
9. History of interstitial lung disease (ILD) requiring corticosteroid therapy, or current ILD, or radiation pneumonitis of Grade ≥2;
10. Severely impaired respiratory function;
11. Active central nervous system (CNS) metastases;
12. History of, or concurrent, central nervous system disorders;
13. History of allergy to recombinant humanized antibodies or human-mouse chimeric antibodies, or hypersensitivity to any excipient component of BL-M08D1;
14. Prior organ transplantation or allogeneic hematopoietic stem cell transplantation;
15. Positive for human immunodeficiency virus (HIV) antibodies, active tuberculosis, active hepatitis B virus infection, or active hepatitis C virus infection;
16. Active infection requiring systemic therapy within 4 weeks prior to the first dose of study drug;
17. Pleural, peritoneal, or pericardial effusion requiring drainage and/or associated with symptoms within 4 weeks prior to the first dose of study drug;
18. Imaging findings indicating that the tumor has invaded or encased major blood vessels (e.g., abdominal or thoracic vessels), the pericardium, or the heart;
19. Use of another investigational drug within 4 weeks or 5 half-lives prior to the first dose;
20. Pregnant or breastfeeding women;
21. Other conditions that, in the opinion of the investigator, make the patient unsuitable for participation in this clinical trial.
