Allogeneic Stem Cell Transplant to Induce Mixed Donor Chimerism in Patients With Sickle Cell Disease and Thalassemia

Sickle cell disease is a genetic disorder in which a mutation in the beta chain of human hemoglobin results in abnormal blood hemoglobin, causing red blood cells to sickle under stress with resulting symptoms including severe pains and strokes. Beta thalassemia is another genetic disorder in which there are abnormal beta hemoglobin chains, causing anemia. In both disorders, frequent red blood cell transfusions may be required to sustain life, but these often result in complications including multiple hospitalizations, iron overload, or bacterial or viral infections such as hepatitis. Standard drugs and therapies used in the treatment of sickle cell disease and/or beta thalassemia provide only supportive care, and may result in long-term side effects, and inadequate control of the disease process. Bone marrow transplant has been increasingly used for the long-term treatment and cure of sickle cell disease and beta thalassemia. Although, not without acute and potential long term side effects, this alternative offers long term control and potential cure of the disease. Most of the side effects seen with bone marrow transplant are directly related to the high intensity of chemotherapy used (ablative).