Impact of Recombinant Human Interleukin-7 (CYT107) on Tumor Clearance and Immune Reconstitution in Multiple Myeloma Patients After Autologous Hematopoietic Cell Transplant

This study is testing whether a drug called CYT107 (recombinant human interleukin-7) can help multiple myeloma patients rebuild their immune system more effectively after a stem cell transplant using their own cells (autologous transplant). Researchers hope that boosting immune recovery after transplant may help the body clear any remaining cancer cells. **You may be eligible if...** - You are 18 or older with confirmed multiple myeloma - Your myeloma is in complete remission or has responded well to treatment (CR, sCR, PR, or VGPR) - Your doctor considers you a good candidate for an autologous stem cell transplant using melphalan conditioning - Your organ function (liver, kidneys, bone marrow) meets required thresholds - You have a backup stem cell graft available **You may NOT be eligible if...** - You are currently taking high-dose steroids (above 5 mg prednisone equivalent daily) - You have a history of T-cell cancer, plasma cell leukemia, or amyloidosis - You are enrolled in another investigational drug study - You have significant lung disease such as severe asthma, COPD, or recent pulmonary embolism - You have uncontrolled infections, heart failure, or unstable heart conditions - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.