View clinical trials related to Severe Aplastic Anemia.
Filter by:The purpose of this study is to analysis of the pharmacokinetics of fludarabine for hematopoietic stem cell transplantation in pediatric patients.
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.
The purpose of this study is to provide an opportunity for patients with malignancies or bone marrow failure states who lack a suitable sibling donor to undergo allogeneic hematopoietic progenitor cell transplantation using cells from unrelated individuals or cord blood registries.
This study is an access and distribution protocol for unlicensed cryopreserved cord blood units (CBUs) in pediatric and adult patients with hematologic malignancies and other indications.
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.
Background: - Severe aplastic anemia (SAA) can lead to problems with bone marrow health and result in low blood cell counts, which require frequent transfusions. Standard treatment for SAA involves injections of antithymocyte globulin (ATG) plus cyclosporine (CsA). This regimen has been shown to improve the blood counts in about two-thirds of patients. However, the ATG/CsA regimen has the following limitations: (a) the disease can come back (relapse) in about one-third of patients who improve initially; and (b) in about 10% to 15% of cases, certain types of bone marrow cancer (such as myelodysplasia and leukemia) can develop (called evolution). Experience with other drugs in SAA such as cyclophosphamide suggests that similar response rates to ATG/CsA can be achieved with a lower risk of relapse and clonal evolution. However, cyclophosphamide was found to have significant side effects in SAA when investigated over 10 years ago due to increase risk of fungal infections. - Better antibiotic drugs against fungus have been developed and are widely used to treat patients who have low white blood cell counts and are at risk of developing infections. In SAA patients in particular, these newer antibiotics have had a large impact in preventing and treating fungus infections. Researchers are revisiting the use of cyclophosphamide in SAA treatment, and plan to give a lower dose of CsA in combination with the immune-suppressing drug cyclophosphamide, as well as antibiotics to protect against infections, as a possible treatment for the disease. Objectives: - To determine the safety and effectiveness of the combination of cyclophosphamide and cyclosporine in treating severe aplastic anemia that has not been treated with immunosuppressive therapy.
Background: - Severe aplastic anemia (SAA) can lead to problems with bone marrow health and result in low blood cell counts, which require frequent transfusions. Standard initial treatment for SAA involves injections of antithymocyte globulin (ATG) plus cyclosporine (CsA). Patients with SAA who do not respond to initial treatment with ATG (refractory) have a high risk of dying without additional treatment. In these cases, for those who do not have a matched bone marrow transplant donor there is no well-defined standard therapy. In our experience with patients who do not respond to horse ATG + CsA, only about one-third of patients who are re-treated with rabbit ATG + CsA improve. Experience with cyclophosphamide in the treatment of refractory severe aplastic anemia suggests that this drug is able to improve blood counts in about 50% of cases. However, the cyclophosphamide regimen has been associated with a significant infection risk (mostly caused by fungus) in studies conducted over 10 years ago due to the lowering of the white blood cell levels. - Better antibiotic drugs against fungus have been developed and are widely used to treat patients who have low white blood cell counts and are at risk of developing infections. In SAA patients in particular, these newer antibiotics have had a large impact in preventing and treating fungus infections. Researchers are revisiting the use of cyclophosphamide at lower doses to minimize its side effects given in combination with another immune suppressant, fludarabine. Objectives: - To determine the safety and effectiveness of the combination of fludarabine plus cyclophosphamide in treating severe aplastic anemia that has not responded to initial treatments.
Background: - Stem cell transplants from related donors (allogenic stem cell transplants) can be used to treat individuals with certain kinds of severe blood diseases or cancers, such as severe anemia. Allogenic stem cell transplants encourage the growth of new bone marrow to replace that of the recipient. Because stem cell transplants can have serious complications, researchers are interested in developing new approaches to stem cell transplants that will reduce the likelihood of these complications. - By reducing the number of white blood cells included in the blood taken during the stem cell collection process, and replacing them with a smaller amount of white blood cells collected prior to stem cell donation, the stem cell transplant may be less likely to cause severe complications for the recipient. Researchers are investigating whether altering the stem cell transplant donation procedure in this manner will improve the likelihood of a successful stem cell transplant with fewer complications. Objectives: - To evaluate a new method of stem cell transplantation that may reduce the possibly of severe side effects or transplant rejection in the recipient. Eligibility: - Recipient: Individuals between 4 and 80 years of age who have been diagnosed with a blood disease that can be treated with allogenic stem cell transplants. - Donor: Individuals between 4 and 80 years of age who are related to the recipient and are eligible to donate blood. OR unrelated donors found through the National Marrow Donor Program. Design: - All participants will be screened with a physical examination and medical history. - DONORS: - Donors will undergo an initial apheresis procedure to donate white blood cells. - After the initial donation, donors will receive injections of filgrastim to release bone marrow cells into the blood. - After 5 days of filgrastim injections, donors will have apheresis again to donate stem cells that are present in the blood. - RECIPIENTS: - Recipients will provide an initial donation of white blood cells to be used for research purposes only. - From 7 days before the stem cell transplant, participants will be admitted to the inpatient unit of the National Institutes of Health Clinical Center and will receive regular doses of cyclophosphamide, fludarabine, and anti-thymocyte globulin to suppress their immune system and prepare for the transplant. - After the initial chemotherapy, participants will receive the donated white blood cells and stem cells as a single infusion. - After the stem cell and white blood cell transplant, participants will have regular doses of cyclosporine and methotrexate to prevent rejection of the donor cells. Participants will have three doses of methotrexate within the week after the transplant, but will continue to take cyclosporine for up to 4 months after the transplant. - Participants will remain in inpatient care for up to 1 month after the transplant, and will be followed with regular visits for up to 3 years with periodic visits thereafter to evaluate the success of the transplant and any side effects.
The purpose of this study is to evaluate the effectiveness of allogeneic transplant after a reduced-intensity preparative regimen for patient, to evaluate survival, and to evaluate the side effects of this treatment. The patient will be in the study for two years for treatment and active monitoring. After treatment and active monitoring are over, the patient's medical condition will be followed indefinitely.
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.