SKB264 in Combination With Pembrolizumab in Subjects With Selected Solid Tumors

Inclusion Criteria:

1. Subjects with Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1 .

2. Subjects with expected survival ≥ 3 months.

3. Cohort A: Subjects with recurrent or metastatic cervical cancer

4. Cohort B: Subjects with locally advanced or metastatic urothelial carcinoma

5. Cohort C: Subjects with recurrent ovarian cancer

6. Cohort D: Subjects with metastatic prostate cancer

7. Subjects have at least one measurable lesion per Response Evaluation Criteria inSolid Tumors (RECIST) 1.1 criteria.

8. Subjects able to provide tumor blocks or slides for biomarker test.

9. Subjects have relatively good organ function and bone marrow function.

10. Subjects must have recovered from all toxicities from previous therapy with theexception of toxicities not considered a safety risk.

11. Contraceptive use by men and women must be consistent with local regulationsregarding the methods of contraception for those participating in clinical studies.

12. Subject is capable of giving signed informed consent.

13. Cohort E: Subjects with advanced endometrial cancer.

Exclusion Criteria:

1. Subjects with active or untreated central nervous system (CNS) metastases and/orcarcinomatous meningitis are not eligible.

2. Subjects who suffer from cardiovascular diseases of clinical significance.

3. Subjects with serious and/or uncontrolled concomitant diseases.

4. Subjects diagnosed active hepatitis B or hepatitis C.

5. Subjects have known human immunodeficiency virus (HIV) infection that is not wellcontrolled.

6. Subjects with known active tuberculosis.

7. Known allergy or hypersensitivity to pembrolizumab or SKB264, or the excipients ofpembrolizumab or SKB264.

8. Subjects with history of allogeneic tissue/solid organ transplant.

9. Subjects previously treated with TROP2 targeted therapy.

10. Subjects who are vaccinated with live vaccine within 30 days before the first dose,or plan to be vaccinated with live vaccine during the study period.

11. Subjects participating in another clinical study, unless it is an observational (non-intervention) clinical study or the follow-up period of an intervention study.

12. The Investigator considers other situations that will interfere with the evaluationof the study intervention or the safety of the subjects or the interpretation of theresults of the study.