A Study of Intravesical FL115 Alone or in Combination With BCG in Non-Muscle Invasive Bladder Cancer

This study is testing a new drug called FL115, alone or combined with BCG (a standard bladder cancer treatment), for people with non-muscle invasive bladder cancer that has stopped responding to BCG therapy. **You may be eligible if...** - You are 18 years or older - You have high-grade non-muscle invasive bladder cancer confirmed by biopsy - Your bladder cancer has stopped responding to BCG treatment - You have declined or are not suitable for bladder removal surgery - Your overall health is reasonably good (ECOG score 0–2) **You may NOT be eligible if...** - Your bladder cancer has spread into the muscle wall or beyond - You have cancer in the upper urinary tract (kidneys or ureters) - You have an active urinary tract infection - You have had previous IL-2 or IL-15 therapy - You have HIV, active hepatitis B, or active hepatitis C - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.