This clinical trial is focused on studying a type of bladder cancer known as Non-Muscle Invasive Bladder Cancer (NMIBC). This form of cancer affects the bladder but does not invade the muscle layer. The study is investigating the effectiveness and safety of a treatment called pembrolizumab, which is also known by its code name MK-3475. Pembrolizumab is a medication that helps the immune system fight cancer cells. In addition to pembrolizumab, the study is also testing combinations with other investigational agents, specifically MK-7684A and MK-4280A. These investigational agents include substances like vibostolimab and favezelimab, which are designed to enhance the body’s immune response against cancer.

The purpose of this study is to evaluate how well these treatments work in patients with high-risk NMIBC that has not responded to a common therapy called Bacillus Calmette-Guerin (BCG). The study aims to see if these treatments can help eliminate the cancer or prevent it from getting worse. Participants in the study will receive the treatments through an intravenous infusion, which means the medication is given directly into a vein. The study will monitor the participants over a period of time to assess the response to the treatment and any side effects that may occur.

Throughout the study, participants will undergo regular check-ups, including procedures like cystoscopy (a test that allows doctors to look inside the bladder), cytology (examining cells from the bladder), and imaging tests to track the progress of the disease. The study will also evaluate the complete response rate, which refers to the absence of detectable cancer, and the disease-free survival rate, which measures how long participants remain free from cancer. The trial is expected to continue until 2030, providing valuable insights into the potential benefits of these treatments for patients with high-risk NMIBC.