[The use of allogeneic bone marrow transplantation and immunosuppressive therapy in the treatment of patients with acquired aplastic anemia]

Abstract

Aim: To evaluate the efficiency of related and unrelated allogeneic bone marrow transplantation (alloBMT) versus immunosuppressive therapy (IST) in patients with aplastic anemia (AA) having no HLA-compatible bone marrow donor.

Subjects and methods: The study covered 61 patients (34 men and 27 women) diagnosed as having acquired AA. Of them, 51 patients were diagnosed as having severe AA, 5 had supersevere AA, and 5 had non-severe AA. Combined IST (antithymocyte globulin (ATG) + cyclosporin A (CsA)) was used in 43 patients; allo-BMT was performed in 18. The basic types of ATG (ATGAM (Pfizer), thymoglobulin (Genzim), ATG (Fresenius), and goat antilymphocyte globulin (ALG) (Research Institute of Gerontology, Ministry of Health of the Russian Federation) were administered. CsA was given in a dose of 5 mg/kg/day. The standard conditioning regimen (ATGAM + cyclophosphanum) and fludarabine-containing (fludarabine + cyclophosphanum + ATG; busulfan + fludarabine + ATG) programs were used in the allo-BMT group. A combination of CsA and metothrexate was given to prevent a graft-versus-host reaction.

Results: Among the IST-receiving patients, overall survival (OS) was 71%. After the first course of IST by follow-up month 6, the response rate was 74%. The second course of IST was performed in 7 patients unresponsive after the first-line IST and in 8 patients with recurrent AA. After the second course of IST, the response rate was 46.7%. Four patients who failed to achieve remission after 2 courses of IST received its third course. A complete response was obtained in 3 patients. In 18 patients following allo-BMT (related and unrelated), OS was 86%; event-free survival was 65. In 12 patients after related allo-BMT, OS was 91.7%.

Conclusion: Related allo-BMT is the method of choice if there is a HLA-compatible sibling. If there are contraindications to it or no related donor, IST with ATG + CsA is indicated. Ineffective IST is an indication for unrelated allo-BMT that may be recommended as life-saving therapy for young patients under 40 years of age.