Aponermin-Based Bridging Therapy Prior to CAR-T Infusion in Relapsed/Refractory Multiple Myeloma Patients With Extramedullary Disease

This study tests a drug called aponermin as a bridge therapy — used to control the cancer while waiting for CAR-T cell treatment to be prepared — in multiple myeloma patients whose cancer has spread outside the bone marrow to soft tissues (called extramedullary disease). **You may be eligible if...** - You are 18 or older with multiple myeloma that has come back or stopped responding to prior treatment - Your cancer has spread to soft tissue outside bones, with tumors at least 2 cm in size - You are planning to receive CAR-T cell therapy - Your general health and organ function are adequate **You may NOT be eligible if...** - You have an active infection - You test positive for HIV, hepatitis B, or hepatitis C - Your liver or kidney function is significantly impaired Talk to your doctor to see if this trial is right for you.