Study BT7480-100 in Patients With Advanced Malignancies Associated With Nectin-4 Expression

This clinical study is evaluating a drug called BT7480 alone and in combination with nivolumab in participants with advanced solid tumors associated with Nectin-4 expression. The main goals of the study are to: * Find the recommended dose of BT7480 that can be given safely to participants alone and in combination with nivolumab * Learn about the side effects and effectiveness of BT7480 alone and in combination with nivolumab * Learn about the effect BT7480 has on the body and how BT7480 is cleared by the body * Learn about the side effects and effectiveness of BT7480 in patients with reduced kidney function