Study Summary
Thalassemia is considered the most common genetic disorder worldwide, occurring with high frequency in Mediterranean areas, the Middle East, Southeast Asia, and the Pacific Islands. Currently, the only cure for thalassemia is bone marrow transplantation from a related, compatible donor. Gene transfer, achieved by transplantation of the patient's own blood stem cells that have been genetically-modified with the corrected gene, could potentially cure thalassemia.
The first step in developing gene transfer for treatment of thalassemia is to develop a safe and effective method to obtain blood stem cells from thalassemia patients. Eventually, high numbers of genetically modified cells will need to be infused into the patient for clinical gene transfer to be effective. The blood stem cells are obtained by giving a "mobilization" agent to the patients. This causes the stem cells to leave the bone marrow and go into the blood. The purpose of this study is to test the safety and effectiveness of the new mobilization agent, Mozobil, in causing mobilization of blood stem cells for patients with beta-thalassemia major.
Interventions
MozobilDRUG
Previously mobilized splenectomized patients who failed to yield sufficient numbers of cells with Mozobil alone will receive low doses G-CSF subcutaneously (starting at 2.5µg/kg/day and adjusted to the degree of leukocytosis), and Mozobil at 240µg/kg starting on the 4th or 5th day of G-CSF, followed by one to three leukaphereses. Previously non-splenectomized patients who failed to yield sufficient numbers of cells with Mozobil alone will receive G-CSF at 10µg/kg/day subcutaneously for 4-7 days, and Mozobil at 240µg/kg starting on the 4th or 5th day of G-CSF, followed by one to three leukaphereses.
MozobilDRUG
Previously mobilized splenectomized patients who failed to yield sufficient numbers of cells with G-CSF in the previous study will receive low doses G-CSF subcutaneously (starting at 2.5µg/kg/day and adjusted to the degree of leukocytosis), and Mozobil at 240µg/kg starting on the 4th or 5th day of G-CSF, followed by one to three leukaphereses. Previously non-splenectomized patients who failed to yield sufficient numbers of cells with G-CSF in the previous study will receive G-CSF at 10µg/kg/day subcutaneously for 4-7 days, and Mozobil at 240µg/kg starting on the 4th or 5th day of G-CSF, followed by one to three leukaphereses.
MozobilDRUG
Up to sixteen patients (splenectomized and non-splenectomized) who were not previously mobilized will receive Mozobil at 240µg/kg for one to three days, followed by one to three leukaphereses.