RC48-ADC in Combination With Gemcitabine in High Risk NMIBC Subjects

This study is testing a combination of two drugs — RC48 (an antibody-drug treatment) and gemcitabine (a chemotherapy) — in people with high-risk bladder cancer that has not yet invaded the bladder muscle. Participants must have already had surgery to remove visible tumors from the bladder lining. **You may be eligible if...** - You are 18 or older - You have been diagnosed with high-risk non-muscle-invasive bladder cancer (confirmed by pathology) - You have completed a procedure called TURBT (surgery to remove bladder tumors) within the past 3 weeks - Your cancer is staged as T1, high-grade, or multiple/recurrent tumors - You have not yet received any drug treatment for this cancer **You may NOT be eligible if...** - You have cancer that has spread into the bladder muscle or beyond - You have already received drug treatment for bladder cancer - You are unable or unwilling to give informed consent Talk to your doctor to see if this trial is right for you.