SKB264 Plus KL-A167 in MSI-H/dMMR Advanced Gynecological Malignancies

Inclusion Criteria:

* 1\. Age ≥18 years.
* 2\. Histologically or cytologically confirmed recurrent or metastatic ovarian cancer, endometrial cancer, or cervical cancer.
* 3\. dMMR or MSI-H subtype (defined as: deficiency/loss of mismatch repair (MMR) proteins MLH1, PMS2, MSH2, or MSH6 expression detected by immunohistochemistry (IHC), or identified as MSI-H by polymerase chain reaction (PCR)/next-generation sequencing (NGS)).
* 4\. Received at least 1 prior systemic regimen (prior anti-PD-1/L1 allowed) for recurrent or metastatic ovarian cancer, endometrial cancer, or cervical cancer.
* 5\. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1.
* 6\. Life expectancy more than 12 weeks.
* 7\. At least one measurable lesion per RECIST 1.1 criteria.
* 8\. Subjects must have recovered from all toxicities related to prior therapies, except for toxicities not considered a safety risk.
* 9\. Adequate function of the important organs.
* 10\. For female subjects of childbearing potential effective medical contraception must be used from the time of signing the informed consent form until 6 months after the last dose of the drug.

  11\. Participants must voluntarily participate in the study, sign an informed consent form, exhibit good compliance, and cooperate with follow-up assessments.

Exclusion Criteria:

* 1\. Subjects with known other malignant tumors that are progressing or require active treatment within the past 3 years.
* 2\. Subjects with known meningeal metastases, brainstem metastases, spinal cord metastases and/or compression, or other active CNS metastases. Subjects with locally treated brain metastases may participate provided they are clinically stable for at least 4 weeks, and without requirement of steroid treatment for at least 14 days prior to first dose of study treatment;
* 3\. Subjects with clinically significant cardiovascular diseases.
* 4\. Subjects with severe and/or uncontrolled concomitant diseases, such as uncontrolled hypertension, symptomatic or recurrent pleural effusion, pericardial effusion, or ascites requiring drainage.
* 5\. Subjects diagnosed with active hepatitis B or active hepatitis C.
* 6\. Subjects with known uncontrolled HIV infection.
* 7\. Subjects with known active tuberculosis.
* 8\. Subjects with documented severe dry eye syndrome, severe meibomian gland dysfunction and/or blepharitis, or a history of corneal disorders that impair or delay corneal healing.
* 9\. Subjects who have undergone major surgery (as defined by the investigator) within 30 days prior to the first dose of study treatment or who have not recovered from prior surgery.
* 10\. Subjects with known hypersensitivity or anaphylaxis to the study drug or its excipients; or a history of severe hypersensitivity reactions to monoclonal antibodies.
* 11\. Subjects with a history of interstitial lung disease (ILD) or non-infectious pneumonia requiring steroid treatment, currently suffering from ILD/pneumonia, or unable to rule out suspected ILD/pneumonia through imaging at screening.
* 12\. Subjects with a history of allogeneic tissue/organ transplantation.
* 13\. Subjects with autoimmune diseases requiring systemic treatment within the past 2 years or requiring immunosuppressive treatment during the study period. Subjects with controllable type 1 diabetes, thyroiditis with normal thyroid function, or hypothyroidism well controlled by hormone replacement therapy (HRT), or skin diseases (such as vitiligo, psoriasis) that do not require systemic treatment can be included.
* 14\. Subjects who have previously received TROP2-targeted drugs or any therapy containing a topoisomerase I inhibitor, including antibody-drug conjugates (ADCs).
* 15\. Subjects who have previously used any experimental anti-tumor vaccines.
* 16\. Subjects who received live vaccines within 30 days prior to the first dose of study treatment or plan to receive live vaccines during the study.
* 17\. Subjects who need to use strong inhibitors or inducers of cytochrome P450 3A4 (CYP3A4) within 2 weeks before the first study treatment and during the study period.
* 18\. Subjects who received any chemotherapy, radiotherapy, immunotherapy, or biologic therapy within 4 weeks prior to the first dose of study treatment; subjects who received small molecule tyrosine kinase inhibitors (TKIs), anti-tumor hormone therapy, systemic immunostimulants (including but not limited to interferon, IL-2), or approved anti-tumor Chinese herbal preparations within 2 weeks before the first study treatment.
* 19\. Subjects who received systemic anti-infective treatment within 2 weeks prior to the first dose of study treatment.
* 20\. Pregnant or lactating women.
* 21\. Any other conditions deemed by the investigator to make the patient unsuitable for participation in this study.