Autologous stem cell transplantation, in which patients’ stem cells are removed before chemotherapy and returned to them afterward to repopulate the blood-forming and immune systems, is commonly used to treat multiple myeloma. In this study, researchers want to see if adding allogeneic stem cell transplantation (infusion of stem cells from a matched donor) to this therapy, along with the drugs busulfan, melphalan, and fludarabine, can increase the cure rate for this disease.
One potential complication of allogeneic stem cell transplantation is graft-versus-host disease (GvHD). GvHD is caused when cells from the donor view the recipient’s cells as foreign, resulting in symptoms such as rash, diarrhea, nausea, and vomiting, among others. Removing the T cells (T-cell depletion) from the donor’s stem cell transplant lowers the risk of GvHD. The allogeneic stem cell transplantation used in this study will be T-cell depleted.
Before the transplant, patient will receive busulfan, melphalan, and fludarabine to rid the bone marrow of cancer. Anti-thymocyte globulin is also used to eliminate any of the patient’s own T cells that survive the chemotherapy, ensuring that the donor’s stem cells are not rejected. Patients will also receive additional white blood cells called lymphocytes from their donors, which help cause a “graft-versus-myeloma” effect and can help the donor stem cells grow.