Stem Cell Transplant May Reverse Sickle Cell Disease
(HealthDay News) — A lower-intensity bone marrow transplant technique may reverse sickle cell disease in adults with severe disease, according to a study published in the July 2 issue of the Journal of the American Medical Association.
Matthew M. Hsieh, MD, from the National Institute of Diabetes and Digestive and Kidney Diseases in Bethesda, MD, and colleagues evaluated 30 patients with severe disease enrolled in this nonmyeloablative transplant study from July 16, 2004–October 25, 2013. The study consisted of alemtuzumab (1mg/kg in divided doses), total-body irradiation (300cGy), sirolimus, and infusion of unmanipulated filgrastim mobilized peripheral blood stem cells (5.5 to 31.7 × 106cells/kg) from human leukocyte antigen-matched siblings.
The researchers found that 29 patients survived a median 3.4 years, with no nonrelapse mortality, while one patient died from intracranial bleeding after relapse. The majority of patients (26; 87%) had long-term stable donor engraftment without acute or chronic graft-versus-host disease. Discontinuation of immunosuppression medication was achieved by 15 engrafted patients, with continued stable donor chimerism and no graft-versus-host disease. Annual mean hospitalization rates were 3.23 the year before, 0.63 the first year after, 0.19 the second year after, and 0.11 the third year after transplant. Thirty-eight serious adverse events occurred, including pain and related management, infections, abdominal events, and sirolimus-related toxic effects.
"The rate of stable mixed-donor chimerism was high and allowed for complete replacement with circulating donor red blood cells among engrafted participants," the authors write.