Phase II Study of Trastuzumab Rezetecan or in Combination With Adebrelimab in HER2-Expressing Locally Advanced or Metastatic Urothelial Carcinoma (la/mUC)

Required: HER2 (ERBB2) expression (IHC 1+ to 3+) (IHC 1+ to 3+)

HER2 expression is defined as immunohistochemical (IHC) staining results of 1+ to 3+, and must be confirmed by the pathology department of Sun Yat-sen University Cancer Center according to ASCO/CAP guidelines

Must have received: systemic therapy — Cohort 1: at least one prior systemic therapy, or relapsed/progressed within 12 months after last treatment, or intolerant due to AEs

Cohort 1: Patients who have received at least one prior systemic therapy, or relapsed/progressed within 12 months after the last treatment, or who could not tolerate treatment due to adverse events (AEs)

Must have received: systemic therapy — Cohort 2: no prior systemic therapy or relapsed/progressed more than 12 months after neoadjuvant/adjuvant therapy, or intolerant due to AEs

Cohort 2: Patients who have not received prior systemic therapy or relapsed/progressed more than 12 months after neoadjuvant/adjuvant therapy, or those who could not tolerate treatment due to AEs

Must have received: platinum-based chemotherapy (cisplatin, carboplatin) — Cohort 3: previously received platinum-based chemotherapy

Cohort 3: Patients who have previously received platinum-based chemotherapy (including cisplatin, carboplatin, etc.)

Must have received: anti-PD-1 therapy — Cohort 3: previously received immunotherapy (including PD-1, PD-L1 inhibitors)

Cohort 3: Patients who have previously received...immunotherapy (including PD-1, PD-L1 inhibitors)

Must have received: antibody-drug conjugate (Disitamab Vedotin) — Cohort 3: previously received Disitamab Vedotin

Cohort 3: Patients who have previously received...Disitamab Vedotin

Cannot have received: antitumor monoclonal antibody

Received antitumor monoclonal antibody treatment within 4 weeks before the study start

Cannot have received: other antitumor therapy

Exception: without recovery from adverse events

received other antitumor therapy without recovery from adverse events

Cannot have received: investigational drug

Participated in any investigational drug treatment within 4 weeks before the study started

Cannot have received: spinal cord radiation

Exception: has not recovered from radiation-related adverse events within 4 weeks before study start

Received spinal cord radiation or has not recovered from radiation-related adverse events within 4 weeks before study start