Alternative immunosuppression in patients failing immunosuppression with ATG who are not transplant candidates: Campath (Alemtuzumab).

Antithymocyte globulin (ATG)-based immunosuppression remains the standard immunosuppressive therapy (IST) for aplastic anemia (AA) patients lacking a sibling donor; however, treatment failures are relatively frequent, including about one-quarter to one-third of patients who do not show any response to initial IST, and about half of the initial responders who may experience subsequent relapses or require continuous maintenance IST. For these patients, there is the option of further IST, which may include additional courses of ATG-based IST, or attempts with alternative IST regimens. Alemtuzumab is a monoclonal anti-CD52 Ab, which has been recently investigated as novel IS agent for the treatment of AA patients. Recent data from different groups have clearly demonstrated the biological efficacy of Alemtuzumab in AA patients, ruling out the initial concerns about possible unacceptable infectious risks secondary to its extremely powerful lympholytic effect. Preliminary data demonstrate a remarkable efficacy, especially in the context of relapsed and, to less extent, refractory patients, whereas data in naïve patients are still limited. On the basis of these results, Alemtuzumab-based immunosuppression is a worthy option for AA and other marrow failure patients requiring a second-line IST. Here we describe a consensus regimen that the European Group for Blood and Marrow Transplantation Severe Aplastic Anemia Working Party suggests for AA patients failing initial IST who are not indicated for SCT.