A Study of TAR-200 in Combination With Cetrelimab, TAR-200 Alone, or Cetrelimab Alone in Participants With Non-Muscle Invasive Bladder Cancer (NMIBC) Unresponsive to Intravesical Bacillus Calmette-Guérin Who Are Ineligible for or Elected Not to Undergo Radical Cystectomy

This study is looking for adults aged 18 or older with a specific type of bladder cancer. Your cancer must be a high-risk non-muscle invasive bladder cancer (NMIBC), meaning it's only on the surface layers of the bladder and hasn't spread deeper. Crucially, your cancer must also have been treated with a standard medicine called BCG, but either it didn't respond or it came back.

You should also be someone who either can't have, or has decided not to have, a major surgery to remove your bladder. Before joining, any visible cancer growths that look like 'papillary disease' must have been removed, but small flat areas of cancer (called CIS) are acceptable for some parts of the study. You'll also need to be generally well enough to take part, as assessed by your doctor.

If you join this study, you would first have health checks to make sure it's right for you. Visible bladder growths would need to be removed before you start. You would then receive one of the study treatments: TAR-200 (given into your bladder), cetrelimab (likely given into a vein), or both. The study involves regular visits to the clinic for medical exams, blood tests, and check-ups of your bladder using a small camera (cystoscopy) to see how the treatment is working. The exact number of visits and the duration of the treatment will depend on which group you're in and how you respond. There will also be follow-up appointments after your treatment finishes to monitor your health. The total time you participate in the study will vary, but it will be over many months, possibly a few years, as we need to see long-term effects.