Clinical Research Details BCG in combination with durvalumab in adult BCG-naive, high-risk NMIBC participants Study Description The PATAPSCO study will explore the combination of durvalumab and BCG (induction and maintenance) in BCG-naïve participants with high-risk NMIBC. This combination may thus provide the dual benefit of decreasing recurrence rates and increasing the duration of response. Inclusion/Exclusion Criteria Inclusion: 1.>/=18 2.Capable of giving informed Consent 3. BCG-Naive or >3 years 4.High-risk tumor: T1, High-grade/G3 tumor, CIS 5. TURBT < 4 months prior 6. No radiotherapy 7. WHO group perfomance status of 0 ro 1 8.Body weight >30 kg 9. life expectancy of at least 12 wks 10. no prior immune-mediated therapy 11. Canidate for BCG treatment 12. WNL lab values 13. Non-pregnant Exclusion: 1. Evidence of muscle-invasive/metastatic cancer 2. Predominantly variant histology 3. lymphovasular invasion of bladder tumor 4. immediate cystectomy is indicated 5. known BCG treatment 6. Concurrent extravesical (ie, urethra, ureter, or renal pelvis), non-muscle-invasive transitional cell carcinoma of the urothelium. 7. involvement in the study, past or present 8. enrollment in another study 9. Treatment with immunostimulatory agents 10. Major surgical procedure within 28 days 11. allogenic organ transplantation 12. Autoimmune or inflammatory disorders 13. Uncontrolled intercurrent illness 14. History of another primary malignancy 15. History of active primary immunodeficiency 16. Active infection 17. Current or prior use of immunosuppressive medication within 14 days 18. Receipt of live attenuated vaccune with 30 days 19. Allergy to interventions 20. Antibiotics with1 week 21. PI discretion Open Enrollment Contact Name: Ashley CarterContact Phone: (904) 244-9962Contact Email: ashley.carter@jax.ufl.edu Investigators K.C. Balaji, M.B.B.S. (M.D.), FRCS, MRCS, LRCP Urology