Study Overview: This study is testing a new treatment called cretostimogene grenadenorepvec for people with a specific type of bladder cancer known as Intermediate Risk Non-Muscle Invasive Bladder Cancer (IR-NMIBC). Participants will have had a procedure called Transurethral Resection of Bladder Tumor (TURBT), which is a way to remove tumors from the bladder.

Study Groups: After TURBT, participants are randomly assigned to one of two groups. Arm A will receive the new treatment, while Arm B will be observed without treatment. Participants in Arm A will get the treatment regularly for up to 13 months if their cancer does not return.

Monitoring: Doctors will check for cancer return every 3 months for the first 2 years, then every 6 months for another year.

• Duration: Up to 3 years monitoring.
• Visits: Regular checks every 3-6 months.
• Potential Benefits/Risks: New treatment may help some patients; usual risks of medical trials apply.