Simcha Samuel

Allogeneic peripheral blood stem cell transplantation using a fludarabine-based low intensity conditioning regimen for malignant lymphoma

relapse is a serious complication following high-dose therapy and autologous bone marrow transplantation (abmt) for malignant lymphoma (ml). allogeneic transplantation (allosct) is a therapeutic option. however, it is associated with a high incidence of transplant-related organ toxicity and mortality. we recently reported fast engraftment and minimal transplant-related toxicity, using fludarabine-based conditioning with reduced amounts of chemotoxic drugs prior to allosct. we now present our experience with 23 heavily treated high risk ml patients who underwent matched allosct following the same low intensity conditioning. the patients (20 male, three female) were aged 13–63 years. nineteen had nhl and four hd (resistant disease 12, partial remission 11). five were post abmt. twenty-two patients had fully matched sibling donors, and one a fully matched unrelated donor. engraftment was fast. there was no rejection or non-engraftment. organ toxicity was moderate with no liver or renal toxicity >grade ii. four patients developed >grade II graft-versus-host disease (GVHD). Seven patients died – four of grade III–IV GVHD and severe infections, two of bacterial sepsis, one of pulmonary failure. Ten patients are alive after 22.5 (15–37) months. Survival and disease-free survival at 37 months are both 40%. Probability of relapse is 26%. These encouraging results suggest that alloSCT following fludarabine-based low intensity conditioning in high-risk patients merits further evaluation. Bone Marrow Transplantation (2000) 25, 1021–1028.

T-cell-depleted allogeneic bone marrow transplantation for acute leukaemia using Campath-1 antibodies and post-transplant administration of donor's peripheral blood lymphocytes for prevention of relapse

One hundred and forty‐six patients with acute leukaemia (81 with ANLL and 65 with ALL) received allogeneic bone marrow transplantation from their fully matched siblings. 121 patients underwent T‐cell depletion (TCD) using Campath 1 monoclonal rat anti‐human lymphocyte (CDw52) antibodies; 67 with Campath 1M and 54 with Campath 1G isotypes. Patients were conditioned for transplant using either total body irradiation combined with chemotherapy (125 patients) or busulfan and cyclophosphamide (21 patients). 112 recipients of T‐cell depleted allografts received in addition total lymphoid irradiation (TLI) for prevention of rejection. Engraftment of neutrophils (>0.5 × 109/l) and platelets (>25 × 109/l) occurred on days 15 and 18, and on days 18 and 20 in recipients of Campath 1M and Campath 1G treated marrows respectively. Rejection was documented in 6.8% of T‐cell depleted transplants. Leukaemia relapse‐free survival at 2 years was 83% for patients transplanted in first CR, 76% in second CR (P2= 0.34) and 42% in advanced leukaemia (P2= 0.009). 81 marrow recipients, 38 with Campath 1M and 43 with Campath 1G treated marrow, received post‐transplant graded increments of donors peripheral blood lymphocytes (PBL) to induce graft‐versus‐leukaemia (GVL) effects. Administration of donors PBL was associated with clinically significant GVHD and with decreased relapse rate especially in patients with ALL. Our data suggest that in patients receiving marrow allografts depleted of T cells by Campath 1 monoclonal antibodies, rejection can be reduced by adequate pregrafting immunosuppression. In patients with advanced disease, post‐transplant cell‐mediated immunotherapy (CMI) using donors PBL may be beneficial; however, further studies are needed to define the optimal schedule of CMI for safe and effective prevention of relapse following TCD bone marrow transplantation in malignant haematological diseases.

Allogeneic stem cell transplantation for severe acquired aplastic anaemia using a fludarabine-based preparative regimen.

We reviewed our experience in the treatment of 13 patients with severe acquired aplastic anaemia, using a newly developed non‐myeloablative regimen consisting of fludarabine (total dose 180 mg/m2), cyclophosphamide (total dose 120 mg/kg), and antithymocyte globulin (total dose 40 mg/kg). All except one patient received multiple transfusions and had failed prior immunosuppressive treatment. Twelve out of 13 patients achieved sustained engraftment. One patient was not evaluable for engraftment because of early death on day +10. None of the patients developed graft failure. Mucositis of mild‐to‐moderate severity was the only observed regimen‐related toxicity. The cumulative incidence of acute graft‐versus‐host disease (GvHD) grade II–IV and III–IV was 8·3% and 0%, respectively. With a median follow‐up period of 45 months, the 5‐year overall survival probability was 84%. Eight out of 11 surviving patients have been followed for more than 1 year and only one developed limited chronic GvHD. All patients enjoy a normal life style, with a Karnofsky score of 100%, and all except three, followed for 3, 5 and 6 months respectively, are free of any immunosuppressive medication. The results of this study look promising, while prospective clinical trials may be required to confirm the benefits of this regimen as an alternative to existing protocols.

Graft-versus-lymphoma effect after allogeneic peripheral blood stem cell transplantation for primary central nervous system lymphoma.

Allogeneic peripheral blood stem cell transplantation (allo PBSCT) is a recognized treatment modality for hematological malignancies resistant to conventional chemoradiotherapy. The post-transplant immune-mediated graft-versus-leukemia effect has major curative potential. In this case presentation, the allogeneic approach to resistant recurrent primary central nervous system (CNS) lymphoma using peripheral blood stem cells from an HLA identical sibling after immuno-suppressive non-myeloablative conditioning, was examined clinically. The patient in question had relapsing refractory primary CNS lymphoma and is the first to be treated with this modality. She developed early skin and liver-localized grade II graft-versus-host disease after allo PBSCT, which then responded to short-term treatment. Chimeric studies at the time showed 100% donor cells and repeated magnetic resonance imaging of the brain revealed gradual shrinkage of the tumor. Three months after transplant the cerebral mass was no longer evident and currently, 30 months after transplantation, the patient continues to be disease free. The absence of any signs of malignancy suggests the development of a durable graft-versus-lymphoma effect in this brain tumor and indicates that this effect may be achieved even after non-myeloablative conditioning.

Low transplant-related mortality with allogeneic stem cell transplantation in elderly patients

Summary:Historically, age >60 years was considered a contraindication for allogeneic stem cell transplantation (allo-SCT). In recent years, elderly (>60 years) patients have become eligible for allo-SCT due to the application of reduced intensity conditioning (RIC). The present report summarizes our cumulative experience in a cohort of 17 elderly patients (age 60–67, median 62.5 years) with hematological malignancies treated with 18 allo-SCT procedures, mostly nonmyeloablative. In all, 14 patients received fludarabine and busulfan/busulfex regimen, three patients were conditioned with the fludarabine and low-dose TBI and one patient received busulfan alone. All patients displayed tri-lineage engraftment. The time to recovery of absolute neutrophil count ⩾0.5 × 109/l was 9–27 days (median 14 days). The time interval to platelet recovery ⩾20 × 109/l was 3–96 days (median 11 days). Veno-occlusive disease occurred only in 3/18 procedures and subsided with conventional treatment. Nonfatal transplant-related complications occurred in 6/18 (33.3%) procedures including: renal failure, arrhythmia, CNS bleeding, cystitis, typhlitis and gastrointestinal bleeding. Transplant-related mortality occurred in 6/18 (33.3%) episodes. Of the 17 patients, 12 (12/18 episodes) were discharged. Five of 17 (29%) patients survived (median follow-up 11 m, range 8–53 m). Our data suggest that RIC-allo-SCT may be safely applied in the elderly, suggesting that allogeneic immunotherapy may become an important tool for treatment of hematological malignancies without an age limit.

Non-myeloablative allogeneic stem cell transplantation focusing on immunotherapy of life-threatening malignant and non-malignant diseases

Allogeneic bone marrow transplantation (BMT) represents an important therapeutic tool for treatment of otherwise incurable malignant and non-malignant diseases. Until recently, myeloablative regimens were considered mandatory for eradication of all undesirable host-derived hematopoietic elements. Our preclinical and ongoing clinical studies indicated that much more effective eradication of host immunohematopoietic system cells could be achieved by adoptive allogeneic cell therapy with donor lymphocyte infusion (DLI) following BMT. Thus, eradication of blood cancer cells, especially in patients with CML can be frequently accomplished despite complete resistance of such tumor cells to maximally tolerated doses of chemoradiotherapy. Our cumulative experience suggested that graft versus leukemia (GVL) effects might be a useful tool for eradication of otherwise resistant tumor cells of host origin. The latter working hypothesis suggested that effective BMT procedures may be accomplished without lethal conditioning of the host, using new well tolerated non-myeloablative regimen, thus possibly minimizing immediate and late side effects related to myeloablative procedures considered until recently mandatory for conditioning of BMT recipients. Recent clinical data that will be presented suggests that safe non-myeloablative stem cell transplantation (NST), with no major toxicity can replace the conventional BMT. Thus, NST may provide an option for cure for a large spectrum of clinical indications in children and elderly individuals without lower or upper age limit, while minimizing procedure-related toxicity and mortality.

A retrospective review of the outcome after second or subsequent allogeneic transplantation.

The failure of allogeneic stem cell transplant (allo-SCT) is cumbersome. We analyzed our experience in a second allo-SCT. Between the years 1981 and 2007, 144 patients underwent 2 or more allo-SCT. The first to second transplant interval ranged from 18 days to 13.25 years (median 98 days). The most frequent indications for the second SCT were activity of the basic disease (78), rejection (37), and engraftment failure (25). Twenty-nine of the 144 (20%) patients transplanted survived more then a year with treatment-related mortality of 45.5% as the leading cause of death. Interestingly, despite the low rate of graft-versus-host disease (GVHD) prophylaxis used, only 51 and 16 of the patients developed acute and chronic GVHD (aGVHD, cGVHD), respectively. Factors indicating higher likelihood for survival were nonmalignant disease, a nonrelapse indication for the second SCT, full HLA-matching, and the use of reduced-intensity conditioning (RIC). Age at transplantation, time interval between transplants, the development of GVHD, conditioning regimen, GVHD prophylaxis, or graft source were not shown to influence the prognosis. With a median follow-up of 4.5 years, 25 patients (17.2%) are alive, and 18 are disease-free. We conclude that although toxic, a second allo-SCT can lead to long-term survival.

ABO Incompatibility is Associated with Increased Non-Relapse and GVHD Related Mortality in Patients with Malignancies Treated with a Reduced Intensity Regimen: A Single Center Experience of 221 Patients

The effect of ABO-incompatibility on transplantation outcome remains a controversial issue, with many of the reported studies showing conflicting results. In this study, we evaluate: the association between ABO-incompatibility and myeloid engraftment; the incidence and severity of acute and chronic graft-versus-host disease (GVHD); non-relapse mortality (NRM); GVHD-associated mortality, relapse and overall survival (OS). Our study includes 221 patients with malignant diseases treated in the same institution with the same reduced intensity regimen. Other variables known to affect the transplantation outcome such as age, disease, disease risk, and donor characteristics were well-balanced between ABO-matched and ABO-mismatched transplants. Analysis of our data shows increased incidence of NRM during the first months after transplantation in the groups of patients with major and minor ABO-incompatibility. Although neither incidence nor severity of GVHD differed significantly among the different groups, we found increased mortality associated with GVHD in the major ABO-incompatible groups. Long-term OS and relapse rate were not different, although we observed a trend for decreased OS during the first year post transplantation in the group of patients with major ABO-incompatibility. Our study showed that ABO-incompatibility has an adverse impact on the transplantation outcome.

Allogeneic cell-mediated and cytokine-activated immunotherapy for malignant lymphoma at the stage of minimal residual disease after autologous stem cell transplantation

Immunocompetent donor-derived T lymphocytes play a crucial role in the elimination of residual leukemic cells post allogeneic bone marrow transplantation. Because this graft versus leukemia (GVL) effect is absent after autologous stem cell transplantation (ASCT), a high rate of relapse ensues. We introduced cell-mediated immunotherapy at the stage of minimal residual disease in lymphoma patients to help effect a GVL-like reaction by adoptive transfer of immunocompetent human leukocyte antigen-matched donor peripheral blood lymphocytes (PBL). Thirteen consecutive patients with high-risk lymphoma were treated with allogeneic cell therapy (AlloCT) after having undergone ASCT. In the absence of graft-versus-host disease, cell therapy-induced graft-versus-lymphoma reaction was amplified by human recombinant interleukin 2 (rlL-2) during 3 days to activate donor PBL in vivo, followed by infusion of in vitro rlL-2 activated donor lymphocytes combined with 3-day rlL-2 therapy. Nine of the patients underwent the treatment protocol well. In the four other patients, in whom the AlloCT resulted in marrow aplasia due to elimination of host hematopoietic cells, treatment with donor marrow cell infusion without further conditioning was performed. Adoptive cell therapy in the form of AlloCT may turn out to be an effective therapeutic modality for the treatment of resistant residual disease in lymphoma patients.

Single Infusion of Donor Mononuclear Early Apoptotic Cells as Prophylaxis for Graft-versus-Host Disease in Myeloablative HLA-Matched Allogeneic Bone Marrow Transplantation: A Phase I/IIa Clinical Trial

Because of its potent immunomodulatory effect, an infusion of donor mononuclear early apoptotic cells (ApoCell) was tested in addition to cyclosporine and methotrexate as prophylaxis for acute graft-versus-host disease (GVHD) after HLA-matched myeloablative allogeneic hematopoietic stem cell transplantation (HSCT) from a related donor. In a phase I/IIa clinical trial, we treated 13 patients (median age, 37 years; range, 20 to 59 years) with hematologic malignancies: 7 patients with acute lymphoblastic leukemia, 5 patients with acute myeloid leukemia, and 1 patient with chronic myeloid leukemia, who received conventional myeloablative conditioning, with 35, 70, 140, or 210 × 10(6) cell/kg of donor ApoCell, on day -1 of transplantation. Engraftment was successful in all patients with median time to neutrophil recovery of 13 days (range, 11 to 19), and platelet recovery of 15 days (range, 11 to 59). Serious adverse effects were reported on 10 occasions in the trial, all of which were considered unrelated (n = 7) or unlikely to be related (n = 3) to ApoCell infusion. The nonrelapse mortality at day 100 and 180 after transplantation was 7.7% and the overall survival at 100 and 180 days after transplantation was 92% and 85%, respectively. All ApoCell preparations showed an in vitro significant tolerogenic effect upon interaction with dendritic cells. The overall incidence of acute grades II to IV GVHD was 23%, whereas among those receiving the 2 higher doses (n = 6), the rate was 0%. These results suggest that a single infusion of donor ApoCell in HLA-matched allogeneic HSCT is a safe and potentially effective prophylaxis for acute GVHD occurring after myeloablative conditioning. No dose limiting toxicity was observed. (Clinicaltrials.gov no. NCT00524784).