Inclusion Criteria:

• Subjects voluntarily participate in this study, sign informed consent and have good compliance.
• The age is ≥ 18 years old (subject to the date of signing the informed consent); Female ; eastern cooperative oncology group (ECOG ) score 0-1 ; estimated survival time ≥ 3 months ;
• Histologically confirmed, unresectable recurrent / metastatic advanced gynecologic tumors;
• The HER2 expression status (IHC 3+, 2+, 1+ or 0) is confirmed in the tumor tissue, and the subjects with completely negative IHC 0 staining are excluded.
• Previous chemotherapy with platinum-based drugs was unsuccessful.
• There is at least one measurable lesion according to the RECIST 1.1 criteria; women of childbearing potential need to meet the following conditions: the serum/urine pregnancy test result is negative before the first administration; they agree to adopt highly effective contraceptive measures (with an annual failure rate of less than 1%) throughout the study period. Women of childbearing potential are defined as premenopausal women who have not had a record of tubal ligation or hysterectomy, or women who have been postmenopausal for no more than 1 year.

Exclusion Criteria:

• Other malignant tumors occurred within the past 5 years before treatment or currently suffered simultaneously.
• Uncontrollable toxic reactions above CTCAE Grade 1 caused by any previous treatment, excluding alopecia.
• Received major surgical treatment, incisional biopsy, or significant traumatic injury within 28 days before the start of treatment.
• Long-term unhealed wounds or fractures.
• Subjects with a history of interstitial lung disease/pneumonia ( non-infectious type ) that required steroid drug intervention treatment in the past, or currently accompanied by interstitial lung disease/pneumonia, or those with suspected interstitial lung disease/pneumonia indicated by screening imaging and cannot be excluded.
• Subjects with moderate to severe pulmonary dysfunction/disease within 3 months before the first administration.
• Arterial/deep vein thrombosis events occurred within 6 months before treatment, such as cerebrovascular accidents, deep vein thrombosis, and pulmonary embolism.
• Subjects with any severe and/or uncontrolled diseases.
• Patients with local recurrence suitable for surgery or radiotherapy.
• Those with disease progression after receiving chemotherapy drugs of topoisomerase I inhibitors or ADC drugs with small molecule toxins as topoisomerase I inhibitors in the previous first-line treatment.
• Any anti-cancer therapy or any other experimental drug treatment within 28 days or 5 half-lives before the first administration in this study.
• Received treatment with Chinese patent medicines with clear anti-tumor indications in the drug instructions approved by National Medical Products Administration (NMPA) within 2 weeks before the first administration in this study.
• Serosal effusion that requires repeated drainage to relieve clinical symptoms, or those who received serosal effusion drainage for treatment purposes within 2 weeks before treatment.
• Patients with clinically significant tumor bleeding or perforation within 1 month before the start of the study treatment, or any bleeding event ≥ CTCAE Grade 3, or patients with bleeding or coagulation disorders who are using warfarin, aspirin, or other antiplatelet aggregation drugs.
• Subjects with known central nervous system metastasis and/or carcinomatous meningitis, with diffuse dissemination. Subjects with a history of brain metastasis may be considered for inclusion if clinically stable.
• Severe bone damage and spinal cord compression caused by tumor bone metastasis, including weight-bearing bone pathological fractures that occurred within 6 months or are likely to occur in the near future, poorly controlled severe bone pain, etc.
• Those allergic to macromolecular drug components or allergic to any research drug, any component or excipient in the drug.
• Received live attenuated vaccines within 4 weeks before treatment.
• Active autoimmune diseases that required systemic treatment (such as using disease-modifying drugs, corticosteroids, or immunosuppressants) within 2 years before the first administration.
• Received systemic glucocorticoid treatment or any other form of immunosuppressive therapy or diagnosed with immunodeficiency within 2 weeks before treatment.