Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018133 (graft-versus-host disease)
 18,032 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dendritic cells (DC) are the most potent antigen-presenting cells (APC) and are pivotal for initiating allograft immunity. Recently, particular DC subsets have been implicated also in allogeneic T cell hyporesponsiveness. Alemtuzumab (anti-CD52, Campath-1H) is a novel T cell depleting antibody that is currently under investigation for the use in allogeneic organ transplantation. While recent studies demonstrated a conspicuous effect of alemtuzumab on peripheral DC in clinical graft-versus-host disease, its efficiency in patients receiving allogeneic organ transplants is still undefined. In the present study we assessed the peripheral DC repertoire in kidney transplant recipients after either alemtuzumab induction therapy followed by FK506 monotherapy or after conventional immunosuppression (FK506, mycophenolate mofetil and steroids) without any induction agent. Induction with alemtuzumab caused a strong and sustained reduction of the total number of peripheral DC and a significant shift from myeloid to plasmacytoid DC subsets (mDC/pDC ratio) as early as 1 month post-transplantation. These data show that alemtuzumab induction targets the peripheral DC repertoire, which might add another mechanism allowing immunosuppressive drug minimization. Further studies are warranted to further elucidate the functional significance of these finding in the setting of allogeneic organ transplantation.
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PMID:Alemtuzumab (Campath-1H) induction therapy and dendritic cells: Impact on peripheral dendritic cell repertoire in renal allograft recipients. 1713 63

The antibody alemtuzumab (anti-CD52) is effective in preventing acute graft-versus-host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (aHSCT). As well as depleting donor T cells, alemtuzumab may also work by targeting host dendritic cells (DC). To determine whether this second mechanism of action is significant, we investigated the effects of intravenous alemtuzumab by comparing skin and blood DC numbers of patients with chronic lymphocytic leukemia, before and after a 4-week course of alemtuzumab treatment. Although skin DC express CD52, the epitope is only weakly detectable and their numbers were not consistently reduced by alemtuzumab. In contrast, circulating blood DC, with stronger CD52 expression, were invariably diminished by alemtuzumab. Because DC depletion in the transplant recipient remains a promising approach for GvHD prophylaxis and therapy, more potent techniques, such as an antibody of different specificity, may be required for effective DC eradication in GvHD target organs.
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PMID:Alemtuzumab depletes dendritic cells more effectively in blood than in skin: a pilot study in patients with chronic lymphocytic leukemia. 1749 45

Alemtuzumab (Campath-1H) is a humanized IgG1 monoclonal antibody that targets the human CD52 antigen. CD52 is expressed by a variety of lymphoid neoplasms and most human mononuclear cell subsets. In 2001, alemtuzumab was approved for marketing in the United States and Europe for use in patients with fludarabine-refractory chronic lymphocytic leukemia (CLL). In heavily pretreated patients with CLL, the overall response rate (ORR) is approximately 35%, and in previously untreated patients the ORR is greater than 80%, with a recent randomized study suggesting it is superior to alkylator-based therapy. Importantly, alemtuzumab is effective in patients with high-risk del(17p13.1) and del(11q22.3) CLL. Alemtuzumab combination studies with fludarabine and/or monoclonal antibodies such as rituximab have demonstrated promising results. Alemtuzumab is also being studied in CLL patients as consolidation therapy for treatment of minimal residual disease, in preparation for stem cell transplantation and to prevent acute and chronic graft versus host disease. Alemtuzumab is frequently associated with acute 'first-dose' reactions when administered intravenously, but is much better tolerated when administered subcutaneously without loss of therapeutic efficacy. Additional potential adverse events associated with alemtuzumab administration include myelosuppression as well as profound cellular immune dysfunction with the associated risk of viral reactivation and other opportunistic infections. Additional studies detailing the mechanism of action of alemtuzumab as well as new strategies for prevention of opportunistic infections will aid in the future therapeutic development of this agent.
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PMID:Alemtuzumab (Campath-1H) in the treatment of chronic lymphocytic leukemia. 1753 18

The treatment of steroid-refractory acute graft-versus-host disease (aGVHD) remains a clinical challenge, for which no standard therapy exists. Alemtuzumab is a humanized anti-CD52 monoclonal antibody (mAb) that has been successfully used as part of conditioning regimens for hematopoietic stem cell transplantation (HSCT) to prevent GVHD. The purpose of this study was to evaluate the safety and efficacy of alemtuzumab in treating steroid-refractory aGVHD (>or=grade II) following HSCT. Eighteen patients received subcutaneous alemtuzumab 10 mg daily on 5 consecutive days. Response was assessed at day 28 following initiation of alemtuzumab. Eight patients had grade II aGVHD, 8 had grade III, and 2 had grade IV. The main organ involved was the liver in 4 patients, gastrointestinal (GI) tract in 5, skin in 3, skin and liver in 3, and skin and GI tract in 3. Fifteen patients (83%) responded to alemtuzumab, including 6 (33%) with complete response. All 3 unresponsive patients died of GVHD. Ten of 15 responders are alive at median follow-up of 11 months (range: 3-24). Infections occurred in 14 patients, including cytomegalovirus (CMV) reactivation in 11. Grade 3 neutropenia and thrombocytopenia occurred in 6 and 4 patients, respectively. Alemtuzumab was well tolerated, and induces promising response rates in steroid-refractory aGVHD.
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PMID:Alemtuzumab for the treatment of steroid-refractory acute graft-versus-host disease. 1815 56

Graft failure is a significant cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). We used a nonmyeloablative conditioning regimen consisting of the lympho-depleting humanized CD52-antibody Campath-1H and fludarabine to rescue 12 consecutive children age 9 months to 17 years with engraftment failure after initial myeloablative HSCT. Primary diagnoses included lymphohematologic malignancies (n=6), severe combined immunodeficiency syndrome (SCID) (n=4), and metabolic diseases (n=2). The same stem cell donor was used as for the primary graft: mismatched family member (n=7), matched unrelated donor (n=4), or matched related donor (n=1). The patients received doses of CD34+ cells that did not significantly differ from those used in the initial, failed transplant. At a median follow-up of 51 months (range, 4 to 84 months), 6 of 6 patients with nonmalignant diseases and 4 of 6 patients with malignancy were alive. Two patients died, 1 patient from pulmonary toxicity and 1 from relapse, at 51 days and 8 months posttransplantation, respectively. All 12 patients initially achieved sustained neutrophil engraftment and complete donor chimerism by day 28. Six patients received donor lymphocyte infusion (DLI) after "rescue" therapy to maintain donor chimerism. At 6 months, 4 patients had complete donor cell engraftment, 4 had 15% to 89% stable donor chimerism, and 3 had developed secondary graft failure. This conditioning regimen was generally well tolerated; 4 of the 12 patients never became neutropenic, and 9 never became thrombocytopenic. Only 1 patient developed graft-versus-host disease (GVHD; grade 1), and none had chronic GVHD. Thus, the regimen that we describe can be used with minimal toxicity to effectively overcome graft failure after myeloablative HSCT in children.
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PMID:Successful treatment of stem cell graft failure in pediatric patients using a submyeloablative regimen of campath-1H and fludarabine. 1894 Jun 85

The humanized anti-CD52 monoclonal antibody alemtuzumab belongs to the family of Campath-1 antibodies, which were initially developed for their ability to prevent graft-versus-host disease (GVHD) and graft rejection in stem cell transplantation. Alemtuzumab is indicated for the treatment of chronic lymphocytic leukaemia (CLL) and has demonstrated considerable activity in relapsed/refractory disease and in previously untreated disease. It has been shown to induce minimal residual disease-negative responses as a single agent or as part of consolidation therapy in a meaningful proportion of patients with CLL and has shown promising activity in patients with high-risk cytogenetic markers. Alemtuzumab may also have significant activity in T-cell malignancies, such as mycosis fungoides and T-cell prolymphocytic leukaemia. Recent studies also have evaluated alemtuzumab as part of a conditioning regimen to prevent GVHD in stem cell transplantation. This article reviews our current understanding of alemtuzumab and discusses its emerging role in the treatment of CLL and other haematological malignancies.
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PMID:Rediscovering alemtuzumab: current and emerging therapeutic roles. 1918 94

Donor lymphocyte infusions (DLI) are used to resolve mixed T-cell chimerism (TCC) after allo-SCT despite a substantial risk of GVHD. We analyzed the impact of prophylactic CD8-depleted (CD8(depl)) DLI in 20 recipients of anti-CD52 alemtuzumab in vivo T-cell-depleted allografts with declining donor TCC after day +60. A total of 13 patients received CD8(depl) DLI and 7 patients did not. All but one of the DLI patients converted to complete donor T-cell chimeras, whereas only one non-DLI patient converted spontaneously. DLI induced transient acute GVHD in five and extensive chronic GVHD in two patients. These data suggest the use of CD8(depl) DLI as an effective treatment for mixed TCC, particularly in patients at high risk for GVHD. We also observed that the majority of reconstituting donor-derived T cells after alemtuzumab conditioning were CD52-negative. CD8(depl) DLI significantly increased the proportion of CD52-positive CD4 T cells, whereby their beneficial effect on reconstituting the post-transplant T-cell repertoire was shown.
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PMID:Donor CD4 T cells convert mixed to full donor T-cell chimerism and replenish the CD52-positive T-cell pool after alemtuzumab-based T-cell-depleted allo-transplantation. 1968 24

Aplastic anemia (AA) is most frequently due to autoimmune attack on its own stem cells. Alemtuzumab is a monoclonal antibody which recognizes the CD52 antigen on the surface of T and B cells. It has proved useful in autoimmune diseases, lymphoproliferative conditions, and graft versus host disease. Based on its immunosuppressive properties, we treated 14 AA patients with alemtuzumab. Median age was 23 years. Ten milligrams of alemtuzumab were injected subcutaneously each day for five consecutive days. Cyclosporine A was also administered orally at a dose of 2 mg/kg every 12 h for 3 months, and then gradually tapered. Response to alemtuzumab was followed for a median of 20 months. There were eight responses (57.1%), two complete and six partial. Whereas six (42.8%) patients were non-responders. Median complete blood count values on alemtuzumab responders were Hb 13.1 mg/dL, absolute neutrophil count 2.4 x 10(9)/L, and platelets 97.5 x 10(9)/L. A good response was produced in 57% of AA patients with the administration of alemtuzumab, who lacked a stem cell donor.
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PMID:Subcutaneous alemtuzumab plus cyclosporine for the treatment of aplastic anemia. 1970 16

The efficacy and safety of CD52 antibody alemtuzumab to treat severe acute GVHD in 18 consecutive patients refractory to standard high-dose corticosteroid therapy is reported. Patients (age range 13-68 years) had developed acute GVHD grade III and IV with gut and/or liver involvement after stem cell transplantation from family donors (n= 7) or HLA-matched unrelated donors (n=11), including five donors with one or two HLA mismatches. Initially, in three patients, start doses of alemtuzumab in the range of 70-80 mg were applied and repeated after 3 to 4 weeks. Impressive responses were seen, but virus reactivation and bacterial infections were frequent. In an attempt to reduce this complication, the next nine patients received a reduced starting dose of 20-33 mg, and the last six patients received 3-13 mg repeated every 2-3 weeks. Seventeen of 18 patients responded to alemtuzumab, six patients are alive with a median follow-up of 108 weeks. Chronic GVHD was observed frequently. Although pronounced lymphocyte depletion requiring close monitoring for signs of infections seems inevitable for efficacy, alemtuzumab given in moderate doses has a substantial activity not only in intestinal but also in severe acute GVHD of the liver.
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PMID:Therapy of steroid-refractory acute GVHD with CD52 antibody alemtuzumab is effective. 2034 71

In vivo alemtuzumab reduces the risk of graft-versus-host disease (GVHD) and nonrelapse mortality after reduced intensity allogeneic transplantation. However, it also delays immune reconstitution, leading to frequent infections and potential loss of graft-versus-tumor responses. Here, we tested the feasibility of alemtuzumab dose deescalation in the context of fludarabine-melphalan conditioning and human leukocyte antigen (HLA)-identical sibling transplantation. Alemtuzumab was given 1-2 days before graft infusion, and dose reduced from 60 mg to 20 mg in 4 sequential cohorts (total n = 106). Pharmacokinetic studies were fitted to a linear, 2-compartment model in which dose reduction led to incomplete saturation of CD52 binding sites and greater antibody clearance. Increased elimination was particularly evident in the 20-mg group in patients who had CD52-expressing tumors at time of transplantation. The 20-mg dose was also associated with greater risk of severe GVHD (acute grade III-IV or chronic extensive) compared with > 20 mg (hazard ratio, 6.7; 95% CI, 2.5-18.3). In contrast, dose reduction to 30 mg on day -1 was associated with equivalent clinical outcomes to higher doses but better lymphocyte recovery at 12 months. In conclusion, alemtuzumab dose reduction to 30 mg is safe in the context of reduced intensity conditioning and HLA-identical sibling transplantation. This trial was registered at http://www.ncrn.org.uk as UKCRN study 1415.
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PMID:Impact of in vivo alemtuzumab dose before reduced intensity conditioning and HLA-identical sibling stem cell transplantation: pharmacokinetics, GVHD, and immune reconstitution. 2058 85


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