This study is for people with a type of bladder cancer called high-risk non-muscle invasive bladder cancer (HR-NMIBC). It aims to find out which treatment method works best: a new system called TAR-200, which delivers a drug called gemcitabine directly to the bladder, used alone or with another drug called cetrelimab, versus a standard treatment called Bacillus Calmette-Guérin (BCG). BCG is a type of bacteria used to treat bladder cancer. The study will last up to 5 years and 2 months, including a period to check if you can join, the treatment itself, and a follow-up phase. You will have to visit the hospital a few times during the study to check your health and see how well the treatment is working.

• The study lasts up to 5 years and 2 months with treatment and follow-up phases.
• You need to visit the hospital several times for check-ups during the study.
• Participants must not have had any previous BCG treatment or certain other types of bladder cancer.