Relatively mild treatment works for most patients in small study
Sickle cell disease in adults might be treatable with a bone marrow transplant, researchers report July 1 in JAMA.
Hundreds of children with sickle cell disease had previously been treated and most cured with the procedure, which requires that their defective bone marrow be largely wiped out by radiation and chemotherapy and then replaced by a closely matched marrow transplant. Until recently, the harsh regimen was considered too risky for adults because they often have accumulated organ damage from sickle cell disease.
In a test of 30 adult patients, 29 have now survived for an average of 3.4 years after undergoing a mild course of radiation and chemo before getting a marrow transplant. The replacement cells act as starters that grow into normal blood without sickle-shaped deformities, which cause pain, anemia, blood flow problems and a need for blood transfusions.
The mild course of radiation and chemo partially wiped out defective marrow, leaving the patients with a mixed batch of marrow cells. The procedure failed to fully replace the abnormal cells in some patients, and one died of bleeding in the brain 10 months after transplant. But one year after transplant, 25 patients had fully functioning blood cells, and 15 have since stopped taking immune-suppressing medication, according to the study coauthors at the National Institutes of Health and Johns Hopkins University.
M. M. Hsieh et al. Nonmyeloablative HLA-Matched Sibling Allogeneic Hematopoietic Stem Cell Transplantation for Severe Sickle Cell Phenotype. JAMA. Vol. 312, July 1, 2014, p. 48. doi:10.1001/jama.2014.7192.
M.M. Hsieh, C.D. Fitzhugh and J.F. Tisdale. Allogeneic hematopoietic stem cell transplantation for sickle cell disease: The time is now. Blood. Vol. 118, August 4, 2011, p. 1197. doi: 10.1182/blood-2011-01-332510.
M.M. Hsieh et al. Allogeneic hematopoietic stem-cell transplantation for sickle cell disease. New England Journal of Medicine. Vol. 361, December 10, 2009, p. 2309. doi: 10.1056/NEJMoa0904971.