Treatment of aplastic anemia with a monoclonal antibody directed against the interleukin-2 receptor.

Severe aplastic anemia (SAA) has been related in most cases to underlying autoimmune conditions. Various immunosuppressive regimens have been recommended in the absence of an HLA-identical bone marrow donor. Prednisolone, antithymocyte globulin, and cyclosporin A have been shown to be effective. This report describes the successful treatment of a 23-year-old woman suffering from severe aplastic anemia who had become multiresistant against previously administered immunosuppressive agents, using a monoclonal IL-2-receptor blocking antibody. The patient responded within 4 weeks. The time to the next relapse was 8 months; however, another remission with a second course of horse-antithymocyte globulin was achieved and has been maintained for 27 months to date with low doses of cyclosporin A. Although this is an anecdotical report, IL-2-receptor blockade using a monoclonal antibody might be considered as a further alternative in multi-resistant SAA, perhaps increasing the susceptibility to further immunosuppressive trials.