View clinical trials related to Severe Aplastic Anemia.
Filter by:Patients with severe, refractory aplastic anemia have a severe, life threatening disease in their bone marrow. Refractory disease means that disease has come back or not responded after receiving one or more immunosuppressive treatments. High dose chemotherapy followed by bone marrow transplantation (BMT) has been used to treat blood diseases like aplastic anemia but complications from Graft vs Host disease (GVHD) and graft failure have limited the survival for those patients. Another study done here at Johns Hopkins has shown that in patients with other diseases (blood cancers) some immunosuppressive drugs given after the BMT has decreased how often patients had complications of GVHD and engraftment failure. This research is being done to find if this approach will help patients with aplastic anemia who have failed other treatments will have better outcomes.
Allogeneic blood and marrow transplantation remains the only viable cure for children who suffer from many serious non-malignant hematological diseases. Transplantation, however, carries a high risk of fatal complications. Much of the risk stems from the use of high dose radiation and chemotherapy for conditioning, the treatment administered just prior to transplant that eliminates the patients' marrow and immune system, effectively preventing rejection of the donors' cells. Attempts to make blood and marrow transplantation safer for children with non-malignant diseases by using lower doses of radiation and chemotherapy have largely failed because of a high rate of graft rejection. In many such cases, it is likely that the graft is rejected because the recipient is sensitized to proteins on donor cells, including bone marrow cells, by blood transfusions. The formation of memory immune cells is a hallmark of sensitization, and these memory cells are relatively insensitive to chemotherapy and radiation. Alefacept, a drug used to treat psoriasis, on the other hand, selectively depletes these cells. The investigators are conducting a pilot study to begin to determine whether incorporating alefacept into a low dose conditioning regimen can effectively mitigate sensitization and, thereby, prevent rejection of allogeneic blood and marrow transplants for multiply transfused children with non-malignant hematological diseases.
The purpose of this study is to discover whether children and adults with Fanconi anemia (FA) can be safely and effectively transplanted with Human Leukocyte Antigen (HLA) mismatched (up to one haplotype), HLA-matched sibling, or unrelated donor stem cells, when leukocytolytic monoclonal antibodies are the sole conditioning agents (patients receiving an HLA mismatched transplant will receive Fludarabine as part of the conditioning regimen). Three monoclonal antibodies (MAb) will be used in combination. Two of them, YTH 24 and YTH 54 are rat antibodies directed against two contiguous epitopes on the CD45 (common leucocyte) antigen. They have been safely administered as part of the conditioning regimen for 12 patients receiving allografts (HLA matched and mismatched) at this center. They produce a transient depletion of >90% circulating leucocytes. The third MAb is Campath 1H, a humanized rat anti-CD52 MAb. This MAb has been widely used to treat B cell chronic lymphocytic leukemia (B-CLL) and more recently has been safely given at this and other centers as part of a sub-ablative conditioning regimen to patients with malignant disease. Because these MAb produce both profound immunosuppression and significant, though transient, myelodestruction we believe they may be useful as the sole conditioning regimen in patients with Fanconi anemia, in whom the use of conventional chemotherapeutic agents for conditioning produces a high rate of short and long term toxicity. We anticipate MAb mediated subablative conditioning will permit engraftment in a high percentage of these patients with little or no immediate or long term toxicity. Campath IH persists in vivo for several days after administration and so will be present over the transplant period to deplete donor T cells as partial graft versus host disease (GvHD) prophylaxis. Additional GvHD prophylaxis will be provided by administration of the medication FK506.
This phase I/II trial studies the side effects of fludarabine phosphate, cyclophosphamide and total-body irradiation followed by donor bone marrow transplant and cyclophosphamide, mycophenolate mofetil, tacrolimus, and sirolimus in treating patients with primary immunodeficiency disorders or noncancerous inherited disorders. Giving low doses of chemotherapy and total-body irradiation before a bone marrow transplant helps prepare the patient's body to accept the incoming donor's bone marrow and decrease the risk that the patient's immune system will reject the donor's stem cells. When the healthy stem cells from a donor are infused into the patient they may help the patient's bone marrow make stem cells, red blood cells, white blood cells, and platelets. Sometimes the transplanted cells from a donor can make an immune response against the body's normal cells called graft versus host disease. Giving cyclophosphamide, mycophenolate mofetil, tacrolimus, and sirolimus after the transplant may help decrease this from happening.
Umbilical cord blood is used as a source of hematopoietic stem cells for bone marrow reconstitution in patients who would be potential candidates for a bone marrow transplant from an unrelated marrow donor. The outcome of transplantation is obtained to assess cord blood myeloid and platelet engraftment, transplant related mortality, overall survival, graft vs. host disease and, for patients with leukemia, lymphoma or myelodysplasia, relapse.