This trial is a registrational Phase III, randomized, open-label, multicenter study to evaluate the efficacy and safety of BL-M07D1 in patients with HER2-expressing platinum-resistant recurrent epithelial ovarian cancer, fallopian tube cancer, and primary peritoneal cancer.

In this trial, the treatment group will receive BL-M07D1, while the control group will receive physician's choice of chemotherapy (liposomal doxorubicin, paclitaxel, or topotecan).

Inclusion Criteria:

1. Voluntarily sign the informed consent form and comply with the protocol requirements;
2. Be ≥18 years and ≤75 years old on the day of signing the informed consent form;
3. Have an expected survival time of ≥3 months;
4. Have histologically or cytologically confirmed epithelial ovarian cancer, fallopian tube cancer, or primary peritoneal cancer;
5. Have previously received a platinum-based regimen and have been confirmed to have platinum-resistant recurrence;
6. Have received a total of ≥1 and ≤3 prior lines of therapy;
7. If previously confirmed to be folate receptor alpha (FRα)-positive, must have received treatment with mirvetuximab soravtansine;
8. Agree to provide archived tumor tissue specimens (from primary or metastatic lesions) collected within 3 years, or fresh tissue samples;
9. Have at least one measurable lesion as defined by RECIST v1.1;
10. Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1;
11. Have recovered from toxicities of prior anti-tumor therapy to ≤ Grade 1 as defined by NCI-CTCAE v5.0;
12. Have no severe cardiac dysfunction, with a left ventricular ejection fraction (LVEF) ≥50%;
13. Meet the required organ function levels;
14. For premenopausal women of childbearing potential, a serum pregnancy test must be performed within 7 days before starting treatment, with a negative result, and must not be breastfeeding; all enrolled patients must use adequate barrier contraception throughout the entire treatment period and for 6 months after treatment completion.

Exclusion Criteria:

1. Received surgical treatment, radical radiotherapy, immunotherapy, etc. within 4 weeks before the first dose;
2. Previously received ADC therapy with a topoisomerase I inhibitor as the payload, or HER2-ADC therapy;
3. History of severe cardiovascular or cerebrovascular disease within six months before screening;
4. Concurrent pulmonary disease resulting in severely impaired lung function;
5. Prolonged QT interval, complete left bundle branch block, third-degree atrioventricular block, or frequent and uncontrolled arrhythmias;
6. Diagnosed with active malignancy within 3 years before study randomization;
7. Unstable thrombotic event requiring therapeutic intervention within 6 months before screening;
8. Hypertension inadequately controlled by two antihypertensive medications;
9. Patients with poorly controlled blood glucose levels;
10. History of ILD treated with steroids, or current ILD, or Grade ≥2 radiation pneumonitis, etc.;
11. Patients with active central nervous system (CNS) metastases;
12. Patients with a history of allergy to recombinant humanized antibodies or to any excipient of BL-M07D1;
13. Prior receipt of organ transplantation or allogeneic hematopoietic stem cell transplantation;
14. Positive for human immunodeficiency virus antibody, active hepatitis B virus infection, or hepatitis C virus infection;
15. Experienced severe infection within 4 weeks before the first dose of study drug;
16. Presence of large serosal cavity effusions, or symptomatic serosal cavity effusions, etc.;
17. Receiving long-term systemic corticosteroid therapy (e.g., >10 mg/day prednisone) prior to randomization;
18. History of severe neurological or psychiatric disorders;
19. Experienced serious non-healing wound, ulcer, or bone fracture within 4 weeks prior to signing informed consent;
20. Subjects with clinically significant bleeding or obvious bleeding tendency within 4 weeks prior to signing informed consent;
21. Intestinal obstruction, Crohn's disease, ulcerative colitis, or chronic diarrhea, etc.;
22. Received other unapproved clinical study drugs or treatments within 4 weeks before study randomization;
23. Subjects who plan to receive or have received a live vaccine within 28 days before the first dose;
24. Presence of other serious physical conditions, abnormal laboratory findings, or poor compliance that may increase the risk of study participation, interfere with study results, or render the patient unsuitable for this study in the investigator's opinion.