View clinical trials related to Stem Cell Transplantation.
Filter by:Background: The gastrointestinal (GI) tract is commonly affected by acute graft-versus-host disease (aGVHD) and chronic GVHD (cGVHD) in patients who have undergone blood or marrow stem cell transplantation (BMT). Initially, patients are treated with systemic corticosteroids, which produce complete response rates in 35 percent. Although short courses of steroids are preferred to minimize adverse effects, many patients require systemic treatment chronically since GI GVHD can negatively impact quality of life and nutrition status. One option to minimize systemic steroid exposure is by nonabsorbable corticosteroids that act locally on the GI tract. Budesonide (Entocort EC, AstraZeneca, Wilmington, DE) is an FDA-approved oral topical corticosteroid for the treatment of mild to moderate active Crohn s disease involving the ileum and/or the ascending colon, and for maintenance of clinical remission of mild to moderate Crohn s disease involving the ileum and/or the ascending colon for up to 3 months. It has a high ratio of topical-to-systemic activity with minimally active metabolites, and undergoes extensive first-pass metabolism. Since both intestinal GVHD and Crohn s disease seem to share a similar pathogenic background, budesonide has been used in the BMT setting for GI GVHD, usually in combination with systemic corticosteroids (e.g. methylprednisolone) to improve clinical response and allow for more rapid tapering of systemic corticosteroid doses. First-pass metabolism is mediated mostly by the cytochrome P450 (CYP450) enzyme system. The liver is the major site of CYP450-mediated metabolism but the enterocytes of the intestinal epithelium are also an important site for drug metabolism. Budesonide undergoes significant metabolism by CYP enzymes with substantial first-pass metabolism. The potential for greater systemic availability of orally administered budesonide exists when it is given concurrently with triazole antifungals, which are commonly prescribed for prophylaxis or treatment of fungal infections after transplantation. Fluconazole and voriconazole are moderate and strong inhibitors of CYP3A4, respectively, and budesonide is a CYP3A4 substrate. Inhibition of CYP3A4 may impair the metabolism of budesonide, resulting in systemic concentrations of budesonide and subsequently, adverse effects such as hyperglycemia. If the presence of fluconazole or voriconazole does impair budesonide s metabolism, then dose adjustments to budesonide may be warranted. There are no prospective studies evaluating the effects of fluconazole or voriconazole on budesonide s pharmacokinetics in patients who have undergone BMT. The primary objective of the proposed study is to determine the effects of fluconazole and voriconazole on the trough (Cmin) and peak (Cmax) of budesonide in patients who have undergone BMT and who have GI GVHD. The primary endpoints are the Cmin and Cmax of budesonide. Secondary endpoints include the Cmin of voriconazole. Objectives: The proposed study seeks to determine the effects of fluconazole and voriconazole on the Cminand Cmax of budesonide. Eligibility: Adult and pediatric subjects (greater than or equal to 13 years of age and greater than or equal to 49 kg) who are registered to an NCI or NHLBI protocol who have undergone a bone marrow, cord, haplo-cord or peripheral blood stem cell transplantation who have GI GVHD as determined by the medical team and who require treatment with budesonide and are candidates for antifungal therapy are eligible for this study. Design: Each subject will serve as his or her own control to minimize the variation in absorption, distribution, metabolism and elimination of oral budesonide that can occur from subject to subject, due to genetic, anatomic or other unidentified differences. For example, genetic polymorphisms of CYP2C19, which is significantly involved in voriconazole s metabolism, could otherwise affect the results of the study (i.e. CYP2C19 poor metabolizers may experience higher voriconazole serum concentrations, which could results in greater CYP3A4 inhibition and higher budesonide exposure). In addition, the longitudinal cohort design of this study will be able to answer the research questions posed with fewer research subjects. Research subjects will be accrued into one of three cohorts depending on the antifungal prophylaxis (or lack thereof) the subject is receiving at study entry and the preference of the medical team for continued antifungal coverage after the initiation of budesonide and systemic corticosteroids. Subjects who are not currently receiving antifungal prophylaxis or who are on fluconazole at baseline are eligible for enrollment in Cohort 1. Subjects in Cohorts 2 and 3 are receiving voriconazole and fluconazole at study entry, respectively. In Cohort 1, if applicable, subjects will stop fluconazole on day -1...
The objective of this trial is to assess the toxicity of thymus transplantation following unrelated umbilical cord blood transplantation. Emphasis will be placed on adverse events that are not typically associated with umbilical cord blood transplantation. Also, to determine whether engraftment of a third party thymus allograft is feasible in patients who have undergone unrelated umbilical cord blood transplantation.
Heart attacks are a leading cause of death in both men and women in the United States. When a person has a heart attack, blood is unable to reach a certain area of the heart, and if the blood supply is not re-established quickly, that area of the heart can suffer permanent damage. While recovery from a heart attack can be managed through medications and lifestyle changes, these treatments can not reverse the original damage to the heart. Current research is focusing on the development of cell-based therapies using stem cells to repair organs that have been irreversibly damaged by disease. A specific form of stem cells, called adult mesenchymal stem cells (MSCs), has shown promise for heart repair. This study will evaluate the safety and effectiveness of injecting MSCs into the heart to repair and restore heart function in people who have had a heart attack and who are having heart surgery for coronary artery bypass grafting (CABG).