Study to Evaluate the Efficacy and Safety of Immunotherapy With Axitinib in Advanced Collecting Duct Carcinoma

This study tests a combination of immunotherapy and a targeted drug (axitinib, a blood vessel blocker) in patients with collecting duct carcinoma — a rare and aggressive type of kidney cancer with very limited treatment options. Participants must have already received at least one prior treatment. **You may be eligible if...** - You are between 18 and 80 years old - You have been diagnosed with collecting duct carcinoma of the kidney that has spread or cannot be removed with surgery - You have received at least one prior systemic treatment - You have at least one measurable tumor and adequate organ function **You may NOT be eligible if...** - You have not received any prior treatment - You have active brain metastases, autoimmune conditions, or serious cardiovascular disease - Your organ function is insufficient to tolerate the treatment Talk to your doctor to see if this trial is right for you.