• Be willing and able to provide written informed consent for the trial.

• Be ≥ 18 years of age on day of signing informed consent.

• Wish to preserve their bladder function or be ineligible for cystectomy.

• Must have undergone transurethral biopsy of the bladder tumor, within 35 days of planned treatment commencement. The patient should have a histologically-confirmed diagnosis of muscle-invasive T2-T4a, N0-1M0 urothelial cell carcinoma of the bladder.

• Must have undergone maximal transurethral resection of the bladder tumour, to an extent that is judged as safe by the urologist performing the resection, within 35 days of planned treatment commencement.

• Subjects with tumors of mixed urothelial/non-urothelial cell histology are allowed, but urothelial cell carcinoma must be the predominant histology (\>50%). Subjects with predominant or exclusively non-urothelial cell histology are not allowed.

• Have planned for chemoradiotherapy as definitive treatment.

• Have a performance status of 0 or 1 on the ECOG Performance Scale

• Have a bladder function that is accessible for cystoscopical follow up.

• Demonstrate adequate organ function. All screening labs should be performed within 28 days of registering the patient on the trial.

• Female participants of childbearing potential should have a negative urine or serum pregnancy within 72 hours prior to registering the patient. If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required.

• Female participants of childbearing potential should be willing to one highly effective method of birth control or be surgically sterile, or abstain from heterosexual activity for the course of the study through 5 month after the last dose of study medication Participants of childbearing potential are those who have not been surgically sterilized or have not been free from menses for \> 1 year.

• Male participants should agree to use condoms starting with the first dose of study therapy through 7 month after the last dose of study therapy.

• Willing to consent to the use of their collected tumor specimen, blood and urine as detailed in the protocol for future scientific research including but not limited to DNA, RNA and protein based biomarker detection.