9MW2821 Combined With Toripalimab Injection in Subjects With Local Advanced or Metastatic Urothelial Cancer

Inclusion Criteria: * Sign and date the informed consent form e approved by independent ethics committe. * Male or female subjects aged 18 to 80 years (including 18 and 80 years). * ECOG status of 0 or 1. * Histologically or cytologically confirmed local advanced or metastatic urothelial cancer * Subjects have received at least 1 line advanced standard therapy or were not treated before * Subjects must submit tumor tissues for test * Life expectancy of ≥ 12 weeks. * Subjects must have measurable lesions according to RECIST (version 1.1). * Adequate organ functions * Sexually active fertile subjects, and their partners, must agree to use methods of contraception during the study and at least 6 months after termination of study therapy. * Subjects are willing to follow study procedures. Exclusion Criteria: * Anti-tumor treatment such as chemotherapy and radiotherapy within 21 days prior to the first dose of study drug. * Major surgery within 28 days prior to first dose of study drug. * PD-1/PD-L1/PD-L2 inhibitors used in the previous treatment for La/m UC. * Previous treatment with ADCs conjugated with MMAE payload. * Clinical significantly toxicity Grade ≥ 2 (except alopecia and pigmentation) related to previous treatment. * Peripheral neuropathy Grade ≥ 2. * Poorly controlled blood sugar. * Increased risks of corneal disease assessed by the investigator prior to the first dose of study drug. * Documented history of clinically significant cardiac or cerebrovascular diseases within 6 months prior to the first dose of study drug. * Active infections, such as uncontrolled HBV/HCV/HIV/TB infection, etc. * Other serious or uncontrolled diseases, such as serious interstitial pneumonia/asthma, serious thromboembolic events, etc. * Poorly controlled central nervous system metastases. * Organ transplantation or allogeneic hematopoietic stem cell transplantation in the past. * History of drug abuse or mental illness. * Known allergic sensitivity to any of the ingredients of the study drug. * Any P-glycoprotein (P-gp) inducers/inhibitors or potent CYP3A4 inducers/inhibitors within 14 days prior to the first dose of study drug. * History of autoimmune disease requiring systemic treatment within 2 years before the first dose. * Any live vaccines within 4 weeks before first dose of study drug or during the study. * Use of any investigational drug or medical instruments within 28 days prior to the first dose of study drug. * History of another malignancy within 3 years before the first dose of study drug. Subjects with curable malignancies are allowed. * Other conditions unsuitable into the study.