This is a multicenter, Phase 2 study to evaluate the efficacy and safety of the anti- programmed cell death-1(PD-1) monoclonal antibody F520 in participants with locally advanced or metastatic Urothelial Cancer (UC).

Inclusion Criteria:

1. Histologically or cytologically confirmed,locally advanced（T4b,any N or any T,N2-3 or metastatic carcinoma（including renal pelvic, ureter bladder and urethra）;

2. Cohort 1：Patients with First-line platinum ineligible must meet criteria for either option a or option b (below):

   1. Has a tumor(s) with PD-L1 combined positive and is considered ineligible to receive cisplatin-based combination therapy, based on 1 of the following:

      • Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 2 within 7 days prior to randomization
      • National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0 Grade ≥2 audiometric hearing loss
      • NCI CTCAE Version 5.0 Grade ≥2 peripheral neuropathy OR

   2. In the opinion of the investigator, is considered ineligible to receive any platinum-based chemotherapy (i.e., ineligible for cisplatin and carboplatin) based on:

      • ECOG PS of 2 within 7 days prior to randomization. and ≥1 of the following:
      • Documented visceral metastatic disease
      • NCI CTCAE Version 5.0 Grade ≥2 audiometric hearing loss
      • NCI CTCAE Version 5.0 Grade ≥2 peripheral neuropathy

Cohort 2: Inoperable Patients in sencond line（or beyond）with locally advanced or metastatic urothelial carcinoma who have disease recurrence or progression during or after a platinum-based chemotherapy regimen;

• Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1
• Calculated creatinine clearance ≥ 30 milliliter (mL)/min (Cockcroft-Gault formula)

Exclusion Criteria:

1. Has received prior therapy with an anti-PD-1, anti-PD-L1 agent or with CTLA-4 receptor;
2. Has a known hypersensitivity to anti-PD-1 / PD-L1 agent;
3. Known pia meningeal metastasis or active central nervous system (CNS) metastasis revealed by CT or MRI. Participants with asymptomatic brain metastases may participate without evidence of progression for at least 1 month.

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.