A Study of BL-B01D1 Combination Therapy in Patients With Metastatic Castration-resistant Prostate Cancer

This study will first conduct a phase II clinical study, and on the basis of the phase II clinical study, subsequent clinical research will be carried out.

Inclusion Criteria: 1. Voluntarily join this study and sign the informed consent form; 2. Age ≥ 18 years; 3. Expected survival time ≥ 3 months; 4. Unresectable metastatic castration-resistant prostate cancer; 5. Meet the definition of mCRPC according to PCWG3 criteria; 6. Agree to provide archived tumor tissue specimens from primary or metastatic lesions within 3 years or fresh tissue samples; 7. Meet the evaluable lesion requirement defined by any one of the following assessment criteria; 8. ECOG performance status score of 0 or 1; 9. Toxicities from prior anti-tumor therapy have recovered to ≤ Grade 1 as defined by NCI-CTCAE v6.0; 10. No severe cardiac dysfunction, with left ventricular ejection fraction ≥ 50%; 11. Organ function levels must meet the required criteria; 12. Urine protein ≤ 1+ or \< 1000 mg/24h; 13. All enrolled patients must use adequate barrier contraceptive measures throughout the entire treatment period and for 7 months after the end of treatment. Exclusion Criteria: 1. Patients with metastatic castration-resistant prostate cancer who are suitable for radical local therapy; 2. Patients with non-prostatic acinar adenocarcinoma confirmed by histopathology or cytology, among others; 3. Patients who have previously received antibody-drug conjugates using topoisomerase I inhibitors as the toxin, among others; 4. Use of chemotherapy, targeted therapy, biological therapy, etc., within 4 weeks or 5 half-lives prior to study randomization; 5. History of severe heart disease or cerebrovascular disease; 6. Long-term systemic corticosteroid therapy with prednisone \>10 mg/day ongoing before the first dose, among others; 7. Active autoimmune diseases and inflammatory diseases; 8. Any thrombotic event within 6 months prior to randomization; 9. Prolonged QTc interval, complete left bundle branch block, etc.; 10. Diagnosis of active malignant tumors within 3 years prior to study randomization; 11. Hypertension inadequately controlled by two antihypertensive medications; 12. Patients with poorly controlled blood glucose; 13. History of ILD requiring steroid therapy, or current ILD, or grade ≥2 radiation pneumonitis; 14. Concurrent pulmonary diseases resulting in clinically severe respiratory function impairment; 15. Patients with active central nervous system metastases; 16. Severe infection occurring within 4 weeks prior to study randomization, etc.; 17. Presence of large serous cavity effusion, or serous cavity effusion with symptoms, etc.; 18. Imaging findings indicating tumor invasion or encasement of the abdomen, chest, etc.; 19. Severe non-healing wounds, ulcers, or fractures within 4 weeks prior to signing informed consent; 20. Trial participants with clinically significant bleeding or obvious bleeding tendency within 4 weeks prior to signing informed consent; 21. Patients with inflammatory bowel disease, history of extensive bowel resection, history of immune-related enteritis, intestinal obstruction, or chronic diarrhea, etc.; 22. Patients with a history of allergy to recombinant humanized antibodies or allergy to the investigational drug; 23. History of autologous or allogeneic stem cell transplantation; 24. Positive for human immunodeficiency virus antibodies, active hepatitis B virus infection, or hepatitis C virus infection; 25. History of severe neurological or psychiatric disorders; 26. Receipt of other unapproved clinical investigational drugs or treatments within 4 weeks prior to study randomization; 27. Trial participants planning to receive vaccination or having received live vaccines within 28 days prior to study randomization; 28. Other conditions deemed by the investigator as unsuitable for participation in this clinical trial due to complications or other circumstances.