This Phase II study is a clinical trial to evaluate the efficacy and safety of BL-B01D1 + pembrolizumab dual therapy with or without bevacizumab (BL-B01D1 + pembrolizumab ± bevacizumab) in patients with recurrent or metastatic cervical cancer and endometrial cancer.

Inclusion Criteria:

1. The subject voluntarily participates in this study and signs the informed consent form;
2. Age ≥18 years and ≤75 years;
3. Expected survival time ≥3 months;
4. ECOG performance status score of 0-1;
5. Patients with recurrent or metastatic cervical cancer or endometrial cancer confirmed by histopathology and/or cytology;
6. Archived tumor tissue samples from the primary or metastatic lesions within the past 3 years must be provided for PD-L1 and other testing;
7. Must have at least one measurable lesion as defined by RECIST v1.1;
8. Organ function levels must meet the requirements;
9. Toxicities from prior anti-tumor therapy must have recovered to ≤ Grade 1 as defined by NCI-CTCAE v5.0;
10. For premenopausal women with childbearing potential, a pregnancy test must be performed within 7 days before starting treatment, and the serum or urine pregnancy test must be negative. Patients must not be lactating. All enrolled patients must use adequate barrier contraception throughout the treatment period and for 6 months after treatment ends.

Exclusion Criteria:

1. Previously received ADC drugs with topoisomerase I inhibitors as the toxin or targeting EGFR and/or HER3;
2. Received chemotherapy, biological therapy, or immunotherapy within 4 weeks or 5 half-lives (whichever is shorter) before the first dose;
3. For Stage II (excluding Cohort 1), subjects who have previously received systemic anti-tumor therapy;
4. Prior immunotherapy resulting in ≥ Grade 3 irAE or ≥ Grade 2 immune-related myocarditis;
5. Used immunomodulatory drugs within 14 days before the first dose of the study drug;
6. Required systemic corticosteroid therapy within 2 weeks before the first dose of the study drug;
7. History of severe cardiovascular or cerebrovascular diseases;
8. Active autoimmune or inflammatory diseases;
9. Other malignancies that progressed or required treatment within 3 years before the first dose;
10. History of ILD/pneumonitis requiring steroid treatment, or current ILD/active pneumonitis;
11. Poorly controlled hypertension (requiring ≥ 2 antihypertensive medications);
12. Poorly controlled diabetes;
13. Unstable thrombotic events requiring therapeutic intervention within 6 months before screening;
14. Active central nervous system metastases;
15. Patients with significant serous cavity effusion, symptomatic effusion, or poorly controlled effusion;
16. History of allergy to recombinant humanized antibodies or any excipients of the investigational drug;
17. Prior organ transplantation or allogeneic hematopoietic stem cell transplantation (Allo-HSCT);
18. Positive for HIV antibody, active tuberculosis, active hepatitis B virus (HBV) infection, or active hepatitis C virus (HCV) infection;
19. Active infection requiring systemic treatment;
20. Participation in another clinical trial within 4 weeks before the first dose;
21. Imaging shows tumor invasion or encasement of major abdominal, thoracic, cervical, or pharyngeal blood vessels;
22. Presence of severe unhealed wounds, ulcers, or fractures within 4 weeks before signing informed consent;
23. Clinically significant bleeding or obvious bleeding tendency within 4 weeks before signing informed consent;
24. Planned or received live vaccines within 28 days before randomization;
25. History of severe neurological or psychiatric disorders;
26. Other conditions deemed by the investigator as unsuitable for participation in this clinical trial.