Leukemia Insights - Winter 2010
In patients with severe Aplastic Anemia who are not candidates for bone marrow transplantation, immunosuppressive therapy is the preferred treatment. Horse-derived antithymocyte globulin (ATG) is the frontline therapy for these patients, but is associated with infusion reactions, serum sickness, and severe allergic reactions in some. Cytopenias and infections during the initial period of treatment can also be a problem. To address some of these challenges and to help optimize the immunosuppressive therapy in patients with MDS based on available data, we have developed a combination “Cytokine Immunotherapy” program for patients with severe Aplastic Anemia.
We are also accepting selected patients with hypocellular MDS who may respond to immunosuppressive therapy. The core of the program consists of rabbit-derived ATG (rATG, Thymoglobulin) in combination with cyclosporine. Additionally, patients receive a steroid taper over 1 month and G-CSF (filgrastim or pegfilgrastim) over several months to support disease or treatment-related neutropenia. Rabbit ATG may be better tolerated than the equine version as is currently indicated for second-line treatment for patients with Aplastic Anemia. The trial is ongoing and demonstrates significant activity (>60% response rate) in patients with aplastic anemia.