OBJECTIVES:~Primary~Determine the safety of alemtuzumab and low-dose cyclosporine, as defined by occurrence of adverse effects, in patients with severe aplastic anemia or single lineage acquired marrow failure.~Determine the efficacy of this regimen, in terms of overall survival, hematological response (partial and complete response, including time to response) and failure-free survival (failure is defined as no response, chronic treatment-maintained response, or relapse), in these patients.~Secondary~Evaluate the incidence of adverse effects after treatment.~Evaluate the long-term safety of alemtuzumab treatment.~Determine the time to achieve a complete hematological response.~Determine the proportion of patients maintaining hematological response free of any treatment.~Determine the incidence of relapse in responding patients.~Determine the incidence of severe infections.~Determine the requirement for IV antibiotics and antifungal therapy.~Determine the requirement for red cell and platelet transfusion.~Determine the incidence of CMV reactivation.~Determine the kinetics of immune reconstitution.~Determine the incidence of paroxysmal nocturnal hemoglobinuria clone (lymphoid or myeloid) development.~Determine the incidence of clonal evolution (i.e., karyotypic abnormalities or secondary myelodysplasia/leukemia).~OUTLINE: Patients receive alemtuzumab subcutaneously on days 1-5*. Patients also receive oral cyclosporine beginning on day 7 and continuing for ≥ 180 days, followed by a taper according to clinical condition.~NOTE: *Patients with single lineage aquired marrow failure receive alemtuzumab on days 1-4.~After completion of study therapy, patients will be followed up every 3 months for up to 2 years.
RATIONALE: Immunosuppressive therapies, such as alemtuzumab and cyclosporine, may improve bone marrow function and increase blood cell counts. Giving alemtuzumab together with cyclosporine may be an effective treatment for severe aplastic anemia or acquired marrow failure.~PURPOSE: This phase II trial is studying the side effects of giving alemtuzumab together with cyclosporine and to see how well it works in treating patients with severe aplastic anemia or acquired marrow failure.