Upon joining the study, participants are randomly assigned to one of three groups. Group A receives a combination of TAR-200 and cetrelimab, Group B receives intravesical BCG, and Group C receives TAR-200 alone.

TAR-200 is a device that releases medication directly into the bladder. Cetrelimab is administered through an intravenous infusion, which means it is given directly into a vein.

The BCG vaccine is administered directly into the bladder through a catheter, a process known as intravesical use.

Participants in Group A receive TAR-200 and cetrelimab. TAR-200 is placed in the bladder every three weeks, while cetrelimab is given as an intravenous infusion every four weeks.

Participants in Group B receive the BCG vaccine intravesically once a week for six weeks, followed by maintenance doses.

Participants in Group C receive TAR-200 alone, which is placed in the bladder every three weeks.

Throughout the study, participants undergo regular monitoring to assess the effectiveness of the treatment and to check for any side effects.

This includes cystoscopies, which are procedures that allow doctors to look inside the bladder, and bladder biopsies, which involve taking small samples of bladder tissue for examination.

Participants are monitored for event-free survival, which means the time until the first recurrence of high-risk disease, progression, or death from any cause.

The study is expected to conclude by May 31, 2028. At the end of the study, the data collected will be analyzed to determine the effectiveness and safety of the treatments.

Participants will have a final assessment to evaluate their health status and any long-term effects of the treatment.