Keith M. Sullivan

Long-Term Comparison of Immunosuppressive Therapy with Antithymocyte Globulin to Bone Marrow Transplantation in Aplastic Anemia

Treatment recommendations for aplastic anemia are based on long-term survival data for recipients of syngeneic or allogeneic bone marrow transplants (BMT) and the more recent results of “immunosuppressive therapy” (1ST), which usually includes antihuman thymocyte globulin (ATG) or antihuman lymphoblast globulin (ALG). Patient age and availability of a suitable marrow donor limit the number of patients who are potential candidates for marrow grafting. Many centers will not recommend an allogeneic BMT for patients with aplasia who are over 40 years of age, although some extend the upper age limit to 50 years. Suitable marrow donors include identical twins, genotypically HLA-identical siblings, or phenotypically HLA-identical family members. Transplants using HLA-mismatched family members or phenotypically identical, unrelated donors are usually reserved for “salvage” therapy after failure of a nontransplant treatment regimen.

Allogeneic and Syngeneic Marrow Transplantation for Aplastic Anemia: Overview of Seattle

Marrow transplantation for the treatment of severe aplastic anemia has to be viewed in the context of alternate therapies for this disease. An earlier study of the International Aplastic Anemia Study Group showed that newly diagnosed patients with severe aplastic anemia treated by supportive therapy with or without androgens had a survival of only 20% at 5 years, with most patients dying within the first 6 months of diagnosis [1]. Most surviving patients had partial or complete spontaneous hematologic recoveries sufficient to live without the need for transfusions. These results were subsequently confirmed by the study group in another cohort of patients [2].