This study tests a new treatment for Non-Muscle Invasive Bladder Cancer (NMIBC), a type of bladder cancer that hasn't spread into the muscle layer of the bladder. The study uses a special form of bacteria, called Recombinant Mycobacterium Bacillus Calmette-Guérin (rMBCG), which is similar to a vaccine. Participants must be 18 or older, with a confirmed diagnosis of bladder cancer, and have not received Bacillus Calmette-Guérin treatment before. The study wants to see if this new treatment can help people with this type of cancer.

• This is a phase 1/2 study, meaning it checks both safety and effectiveness.
• Participants need a good health status and should not have other severe health issues.
• Women must not be pregnant or nursing, and must use birth control during the study.