Inclusion Criteria:  Resectable muscle-invasive UC (upper urinary tract allowed), defined as: cT2-4aN0M0 OR cT1-4aN1-3M0 World Health Organization (WHO) performance Status 0 or 1. Urothelial cancer is the dominant histology (>70%). Formalin-fixed paraffin-embedded (FFPE) tumor specimens in paraffin blocks from diagnostic TUR available (or equivalent FFPE tumor specimens for upper tract tumors; at least two biopsy cores available). PD-L1 status must be determined Screening laboratory values must meet the following criteria: WBC ≥ 2.0x109/L, Neutrophils ≥1.0x109/L, Platelets ≥100 x109/L, Hemoglobin ≥5.5 mmol/L, GFR>30 ml/min as per Cockcroft-Gault formula, AST ≤ 1.5 x ULN, ALT ≤1.5 x ULN, Bilirubin ≤1.5 X ULN Negative pregnancy test (βHCG in urine or blood) for female patients of childbearing potential within 2 weeks prior to Day 1 Cycle 1. Highly effective contraception for both male and female subjects if the risk of conception exists. Female patients of childbearing potential must have a negative urine or serum pregnancy test before receiving the first dose of study medication and must comply with contraception methods as requested by the study protocol  Exclusion Criteria:  Subjects with active autoimmune disease in the past 2 years. Patients with diabetes mellitus, properly controlled hypothyroidism or hyperthyroidism, vitiligo, psoriasis or other mild skin disease can still be included. Documented history of severe autoimmune disease (e.g. inflammatory bowel disease, myasthenia gravis). Prior CTLA-4 or PD-1/PD-L1-targeting immunotherapy. Known history of Human Immunodeficiency Virus infection or tuberculosis, or other active infection requiring therapy at the time of inclusion. Positive tests for Hepatitis B surface antigen or Hepatitis C ribonucleic acid (RNA) Underlying medical conditions that, in the investigator's opinion, will make the administration of study drug hazardous or obscure the interpretation of adverse events Medical condition requiring the use of immunosuppressive medications, with the exceptions of intranasal and inhaled corticosteroids or systemic corticosteroids at physiological doses, which are not to exceed 10 mg/day of prednisone, or an equivalent corticosteroid. Steroids as premedication for hypersensitivity reactions (e.g., CT scan premedication) will be allowed. Use of other investigational drugs five half lives before study drug administration Malignancy, other than urothelial cancer, in the previous 2 years, with a high chance of recurrence (estimated >10%). Patients with low risk prostate cancer (defined as Stage T1/T2a, Gleason score ≤ 6, and PSA ≤ 10 ng/mL) who are treatment-naive and undergoing active surveillance are eligible. Pregnant and lactating female patients. Major surgical procedure within 4 weeks prior to enrolment or anticipation of need for a major surgical procedure during the course of the study other than for diagnosis. Severe infections within 2 weeks prior to enrolment in the study including but not limited to hospitalization for complications of infection, bacteremia, or severe pneumonia. Significant cardiovascular disease, such as New York Heart Association cardiac disease (Class II or greater), myocardial infarction within 3 months prior to enrolment, unstable arrhythmias and unstable angina. Conditions requiring systemic anti-arrhythmic therapy known to prolong QT/QTc interval. Patients with QTcF interval >480 msec on at least two separate and consecutive ECGs at screening or a medical history of long-QT-Syndrome. Previous intravenous chemotherapy for bladder cancer. Prior low-dose sensitizing chemotherapy used for combined modality treatment, or radiation alone, is allowed if patients have recurred after an initial response. Patients with residual disease after (chemo)radiation for bladder cancer are not eligible. Patients in whom use of a colon segment for urinary diversion is planned.