A Phase II Study of AK146D1 Mono or Combined With AK112 in Advanced Urothelial Carcinoma

Inclusion Criteria: * Be able to understand and voluntarily sign the written informed consent form. * Age 18-75. * ECOG PS 0 or 1. * Expected lifespan ≥3 months. * Histologically or cytologically documented Urothelial carcinoma. * At least one measurable lesion according to RECIST v1.1. * Sufficient organ function. Exclusion Criteria: * Having other active malignancies within 3 years. * Currently participating in another interventional clinical study. * Presence of active metastases to the central nervous system. * Prior chemotherapy agent targeting topoisomerase I . * Receipt of systemic anti-tumor therapy within 4 weeks prior to the first dose. * Patients with clinically significant cardiovascular or cerebrovascular diseases or risks. * Patients with active autoimmune diseases requiring systemic treatment within 2 years. * Receipt of systemic anti-infective therapy within 2 weeks prior to the first dose. * Previous history of severe hypersensitivity reactions. * Patients with a history of mental illness and incapacitated or limited capacity. * Any disease or condition that, in the opinion of the investigator, would compromise patient safety or interfere with study assessments.