High-dose immunosuppressive therapy with autologous hematopoietic stem cell transplantation as a treatment option in multiple sclerosis

High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic stem cell transplantation (auto-HSCT) is a new and promising approach to the treatment of multiple sclerosis (MS) patients because currently there are no effective treatment methods for this disease. In this article, we present results of a prospective clinical study of efficacy of HDIT + auto-HSCT in MS patients. The following treatment strategies were employed in the study: "early," "conventional," and "salvage/late" transplantation. Fifty patients with various types of MS were included in this study. No toxic deaths were reported among 50 MS patients; transplantation procedure was well-tolerated by the patients. The efficacy analysis was performed in 45 patients. Twenty-eight patients achieved an objective improvement of neurological symptoms, defined as at least 0.5-point decrease in the Expanded Disability Status Scale (EDSS) score as compared to the baseline and confirmed during 6 months, and 17 patients had disease stabilization (steady EDSS level as compared to the baseline and confirmed during 6 months). The progression-free survival at 6 years after HDIT + auto-HSCT was 72%. Magnetic resonance imaging data were available in 37 patients before transplantation showing disease activity in 43.3%. No active, new, or enlarging lesions were registered in patients without disease progression. In conclusion, HDIT + auto-HSCT suggests positive results in management of patients with different types of MS. Identification of treatment strategies based on the level of disability, namely "early," "conventional," and "salvage/late" transplantation, appears to be feasible to improve treatment outcomes.     

Autologous hematopoietic cell transplantation following high-dose immunosuppressive therapy for advanced multiple sclerosis: long-term results

The purpose of the study was to determine the long-term safety and effectiveness of high-dose immunosuppressive therapy (HDIT) followed by autologous hematopoietic cell transplantation (AHCT) in advanced multiple sclerosis (MS). TBI, CY and antithymocyte globulin were followed by transplantation of autologous, CD34-selected PBSCs. Neurological examinations, brain magnetic resonance imaging and cerebrospinal fluid (CSF) for oligoclonal bands (OCB) were serially evaluated. Patients (n=26, mean Expanded Disability Status Scale (EDSS)=7.0, 17 secondary progressive, 8 primary progressive, 1 relapsing/remitting) were followed for a median of 48 months after HDIT followed by AHCT. The 72-month probability of worsening 1.0 EDSS point was 0.52 (95% confidence interval, 0.30-0.75). Five patients had an EDSS at baseline of 6.0; four of them had not failed treatment at last study visit. OCB in CSF persisted with minor changes in the banding pattern. Four new or enhancing lesions were seen on MRI, all within 13 months of treatment. In this population with high baseline EDSS, a significant proportion of patients with advanced MS remained stable for as long as 7 years after transplant. Non-inflammatory events may have contributed to neurological worsening after treatment. HDIT/AHCT may be more effective in patients with less advanced relapsing/remitting MS.     

CD34+ selected autologous peripheral blood stem cell transplantation for multiple sclerosis: report of toxicity and treatment results at one year of follow-up in 15 patients

BACKGROUND AND OBJECTIVES: Autologous stem cell transplantation (ASCT) is currently being evaluated as a therapy for patients with multiple sclerosis (MS). We report the results of a phase II trial to evaluate feasibility and toxicity of CD34+ selected ASCT (CD34+/ASCT) and treatment results at one year of follow-up. DESIGN AND METHODS: Patients with advanced secondary progressive (SP) or relapsing-remitting (RR) MS and confirmed worsening of the extended disability status scale (EDSS) in the previous year despite interferon or other immunotherapies were included. Peripheral blood stem cells were obtained by leukaphereses after mobilization with cyclophosphamide (Cy) and granulocyte colony-stimulating factor (G-CSF). CD34+ selection was performed by means of an Isolex 300 or CliniMACS device. BCNU, Cy and antithymocyte globulin (ATG) were administered as conditioning regimen. RESULTS: Fifteen patients (9 SPMS and 6 RRMS) with a median EDSS of 6.0 (4.5-6.5) and a median of 3 (1-7) relapses in the previous year were included. Mobilization was unsuccessful in one patient. During mobilization, one patient had a transient neurologic deterioration. The main complication during ASCT were engraftment syndrome, which developed in three patients, CMV reactivation in one, and neurologic deterioration in two patients coinciding with high-fever related to ATG. Hematologic recovery was fast and complete in all cases. At 12 months, the EDSS had improved in three patients, worsened in two and remained stable in nine. Despite withdrawal of all immunosuppressive therapy only two patients had relapses. Magnetic resonance imaging showed disappearance of enhanced T1 lesions but oligoclonal bands persisted in the cerebrospinal fluid of all evaluated cases. INTERPRETATION AND CONCLUSIONS: CD34+/ASCT using BCNU, Cy and ATG as conditioning regimen has an acceptable toxicity and clearly reduces the progression of MS. Further follow-up is necessary to establish the real impact of this procedure on the long-term evolution of the disease.     

Autologous Peripheral Blood Stem Cell Transplantation for Severe Multiple Sclerosis

We describe the results of a clinical trial to evaluate the feasibility and toxicity of autologous hematopoietic stem cell transplantation (auto-HSCT) for patients with progressive multiple sclerosis (MS). Fifteen patients (all patients with secondary progressive MS) were enrolled. The median expanded disability status scale (EDSS) score at baseline was 6.0 (range, 4.5-7.5). Peripheral blood stem cells were obtained by leukapheresis after mobilization with granulocyte colony-stimulating factor. In 9 patients, CD34+ cell selection was performed with a CliniMACS cell selection system, and 6 patients accepted infusion of unmodified peripheral blood stem cells. The modified BEAM (carmustine, teniposide, cytarabine, and melphalan) was the sole conditioning regimen used. The adverse effects included infections, mucositis, transient hepatotoxicity, and diarrhea. Three patients had flares of neurologic deterioration during mobilization, 8 patients had the same manifestation during transplantation, and 2 patients had similar flares within 3 months of transplantation. Six patients experienced continuous neurologic improvement after transplantation, 5 patients experienced neurologic progression, and 4 patients had stabilization of their disease. The confirmed progression-free rate was 63.8% at 49 months. The results of lymphocyte purging were no better than for no purging. Auto-HSCT proved to be safe and beneficial for some MS patients. Further studies are needed to establish the merit of this procedure for MS patients.     

Hematopoietic stem cell transplantation for progressive multiple sclerosis: failure of a total body irradiation-based conditioning regimen to prevent disease progression in patients with high disability scores

There were 21 patients with rapidly progressive multiple sclerosis (MS) treated on a phase 1/2 study of intense immune suppressive therapy and autologous hematopoietic stem cell (HSC) support with no 1-year mortality. Following transplantation, one patient had a confirmed acute attack of MS. Neurologic progression defined by the expanded disability status scale (EDSS) did not increase in disability by 1.0 or more steps in any of 9 patients with a pretransplantation EDSS of 6.0 or less. In 8 of 12 patients with high pretransplantation disability scores (EDSS > 6.0), progressive neurologic disability as defined by at least a 1-point increase in the EDSS has occurred and was manifested as gradual neurologic deterioration. There were 2 patients with a pretransplantation EDSS of 7.0 and 8.0 who died from complications of progressive disease at 13 and 18 months following treatment. Our experience suggests that intense immune suppression using a total body irradiation (TBI)-based regimen and hematopoietic stem cell transplantation (HSCT) are not effective for patients with progressive disease and high pretransplantation disability scores. Further studies are necessary to determine the role of intense immune suppressive therapy and HSC support in ambulatory patients with less accumulated disability and more inflammatory disease activity. Specifically, more patients and longer follow-up would be required in patients with an EDSS of 6.0 or less before drawing conclusions on this subgroup.     

Autologous HSCT for severe progressive multiple sclerosis in a multicenter trial: impact on disease activity and quality of life

Hematopoietic stem cell transplantation (HSCT) has been proposed for the treatment of severe multiple sclerosis (MS). In a phase 2 multicenter study we selected 19 non-primary progressive MS patients showing high disease activity on the basis of both brain magnetic resonance imaging (MRI) and sustained clinical deterioration despite conventional treatments. After stem cell mobilization with cyclophosphamide (CY) and filgrastim, patients were conditioned with BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea), cytosine arabinoside, etoposide, and melphalan (BEAM) followed by antithymocyte globulin (ATG). Unmanipulated peripheral blood stem cells (PBSCs) were then infused. No maintenance treatment was administered with a median follow-up of 36 months (range, 12 to 72 months). All patients showed clinical stabilization or improvement; 3 subsequently deteriorated, 1 beyond the baseline. No MRI active lesions were detected after the HSCT except in 1 patient who showed a new lesion at 4.5 years. Infections were limited and restricted to 3 months after HSCT. Health-related quality of life was assessed through the 54-item MS quality of life (MSQOL-54) questionnaire, showing a statistically significant improvement in both composite scores and in most of the individual domains. HSCT is able to induce a prolonged clinical stabilization in severe progressive MS patients, resulting in both sustained treatment-free periods and quality of life improvement.     

No indication of increased infection rates using low‐dose alemtuzumab instead of anti‐thymocyte globulin as graft‐versus‐host disease prophylaxis before allogeneic stem cell transplantation

Background

Alemtuzumab as part of the conditioning protocol is effective in reducing graft‐versus‐host disease (GvHD), but may be associated with increased infection rates, especially when using high doses (ie, 100 mg).

Methods

We performed a retrospective, single‐center, case‐control study analyzing the rates of neutropenic fever, cytomegalovirus (CMV) reactivation, Epstein‐Barr virus (EBV) reactivation, clinical manifest toxoplasmosis, and clinical manifest human herpesvirus‐6 (HHV6) infection using low‐dose alemtuzumab in comparison with anti‐thymocyte globulin (ATG) as GvHD prophylaxis before allogeneic stem cell transplantation. Forty‐four patients transplanted from unrelated donors between 2001 and 2012 were matched by age, diagnosis, and conditioning regimen and treated either with alemtuzumab 10 mg at day ?2 (respectively, 20 mg in case of mismatch transplantation) or ATG. ATG Fresenius (10 mg/kg for 3 days) or Thymoglobulin (2 mg/kg for 3 days) were used.

Results

Rates of CMV reactivation, EBV reactivation, and clinical manifest HHV6 infection or toxoplasmosis did not differ significantly between both groups until 2 years after transplantation. No case of post‐transplant lymphoproliferative disorder was observed. Also, rates of neutropenic fever during inpatient treatment after transplantation did not differ significantly in both groups.

Conclusion

We saw no indication of increased infections rates when using low‐dose alemtuzumab as GvHD prophylaxis before allogeneic stem cell transplantation in this retrospective analysis.     

High-dose immunosuppressive therapy with PBPC support in the treatment of poor risk multiple sclerosis

High-dose immunoablative chemotherapy with autologous haematopoietic cell support might be beneficial in the treatment of intractable forms of MS. We mobilised PBPC in 11 patients with secondary progressive MS and finally eight patients were grafted after high-dose BEAM chemotherapy with either in vitro or in vivo T cell depletion. Median EDSS and SNRS scores at the time of inclusion were 6.5 (6.5-7.5) and 56 (44-65), respectively. PBPC mobilisation was safe with no serious adverse effects, and without significant aggravation of disability. One patient improved significantly (by 1.0 point on EDSS) after the mobilisation. Two mobilisation failures were observed. No life-threatening events occurred during the transplantation. All grafted patients, except one, at least stabilised their disability status. One patient improved significantly (by 1.5 points on EDSS), two patients improved slightly (by 0.5 points on EDSS), one patient worsened by 1.0 point on the EDSS in 10 months. Improvement occurred with a delay of 2-4 months. Median EDSS and SNRS of grafted patients at the last follow up were 6.5 (5.5-8.5) and 64 (39-73), respectively with median follow-up of 8.5 months. Further follow-up is needed to determine the disease course after complete immune reconstitution. Bone Marrow Transplantation (2000) 25, 525-531.     

Effect of ATG‐F on B‐cell reconstitution after hematopoietic stem cell transplantation

Antithymocyte globulin Fresenius (ATG‐F) is used before hematopoietic stem cell transplantation to prevent graft rejection and graft‐versus‐host disease in patients with HLA‐matched unrelated donors or mismatched volunteers. However, little is known about the effect of ATG‐F on the reconstitution of B‐cell subsets. Sixty‐seven patients were longitudinally studied at day 15, day 30, and then monthly after hematopoietic stem cell transplantation. Conditioning regimes included ATG‐F, which was infused at days 3, 2 and 1 at a dosage of 10 mg/kg/d. Twenty‐seven patients received conditioning regimes without ATG. ATG‐treated patients showed a significant delay of CD19+ B cells in the early recovery period. The absolute numbers of circulating CD19+ B cells were significantly lower (P < 0.05) up to 5 months post‐transplantation compared to non‐ATG patients. The recovery of the memory compartment was delayed in both groups and did not reach normal values 1‐year post‐transplantation. ATG‐treated patient showed significantly lower absolute numbers of circulating CD27+ memory B cells in the first‐month after transplantation compared to non‐ATG patients. In conclusion, treatment with ATG in the conditioning regime of patients undergoing allogeneic hematopoietic stem cell transplantation leads to a significant delay of CD19+ B cells. Thus, ATG seems also to negatively influence B‐cell immune reconstitution.     

High-dose immunosuppressive therapy and autologous hematopoietic cell transplantation for severe systemic sclerosis: long-term follow-up of the US multicenter pilot study

More effective therapeutic strategies are required for patients with poor-prognosis systemic sclerosis (SSc). A phase 2 single-arm study of high-dose immunosuppressive therapy (HDIT) and autologous CD34-selected hematopoietic cell transplantation (HCT) was conducted in 34 patients with diffuse cutaneous SSc. HDIT included total body irradiation (800 cGy) with lung shielding, cyclophosphamide (120 mg/kg), and equine antithymocyte globulin (90 mg/kg). Neutrophil and platelet counts were recovered by 9 (range, 7 to 13) and 11 (range, 7 to 25) days after HCT, respectively. Seventeen of 27 (63%) evaluable patients who survived at least 1 year after HDIT had sustained responses at a median follow-up of 4 (range, 1 to 8) years. There was a major improvement in skin (modified Rodnan skin score, -22.08; P < .001) and overall function (modified Health Assessment Questionnaire Disability Index, -1.03; P < .001) at final evaluation. Importantly, for the first time, biopsies confirmed a statistically significant decrease of dermal fibrosis compared with baseline (P < .001). Lung, heart, and kidney function, in general, remained clinically stable. There were 12 deaths during the study (transplantation-related, 8; SSc-related, 4). The estimated progression-free survival was 64% at 5 years. Sustained responses including a decrease in dermal fibrosis were observed exceeding those previously reported with other therapies. HDIT and autologous HCT for SSc should be evaluated in a randomized clinical trial.     

Adverse effects of anti-thymocyte globulin/anti-lymphocyte globulin therapy]

This single-centre study evaluated the adverse effects of anti-thymocyte globulin (ATG) and anti-lymphocyte globulin (ALG) as used for the treatment of aplastic anemia and/or for conditioning regimens prior to stem cell transplantation. ATG/ALG was given to 29 patients a total of 37 times. The incidence of adverse effects was 62.1% (23/37), and fever was the most frequent adverse effect. Therapy was discontinued in only 4 patients (10.8%) due to severe adverse effects. Adverse effects occurred more frequently with ATG (rabbit-derived) than with ALG (horse-derived). Seven patients underwent 2 or 3 cycles of ATG/ALG therapy, for a combined total of 8 times; 6 of those patients (75% (6/8)) experienced adverse effects. Shorter intervals between repeated cycles of therapy appeared to heighten the risk of adverse reactions.     

Outcomes of reduced-intensity transplantation for chronic myeloid leukemia: an analysis of prognostic factors from the Chronic Leukemia Working Party of the EBMT

This study reports outcomes of allogeneic hematopoietic stem cell transplantation with reduced-intensity conditioning (RIC) in 186 patients with chronic myeloid leukemia (CML) from the European Group for Blood and Marrow Transplantation (EBMT). The median age was 50 years, and 64% were in first chronic phase (CP1), CP2 13%, accelerated phase 17%, and blast crises 6%. The median EBMT transplant score was 3. The day 100 transplantation-related mortality (TRM) was 6.1% (confidence interval [CI], 3.4%-11%) but rose to 23.3% (CI, 14%-27%) at 2 years. Fludarabine, busulfan, and antithymocyte globulin (Fd/Bu/ATG) was associated with the lowest TRM of 11.6% (CI, 4.7%-11%) at 1 year. Acute graft-versus-host disease (GvHD) grade II to IV occurred in 32% and chronic GvHD in 43% (extensive in 24%). ATG was associated with a lower incidence of chronic GvHD (cGvHD). The overall survival (OS) and progression-free survival (PFS) at 3 years were 58% (CI, 50%-66%) and 37% (CI, 30%-45%), respectively. Adverse OS was associated with advanced disease (relative risk [RR], 3.4). PFS was inferior in advanced disease (RR, 2.7) and a trend to improved outcomes with Fd/Bu/ATG (RR, 0.58). RIC allografts are feasible in CML in first or second CP. Since no other RIC regimen demonstrated superiority, Fd/Bu/ATG should be considered as baseline in future prospective trials.     

Disability in multiple sclerosis is associated with age and inflammatory,metabolic and oxidative/nitrosative stress biomarkers: results of multivariate and machine learning procedures

The aim of this study was to evaluate the immune-inflammatory, metabolic, and nitro-oxidative stress (IM&NO) biomarkers as predictors of disability in multiple sclerosis (MS) patients. A total of 122 patients with MS were included; their disability was evaluated using the Expanded Disability Status Scale (EDSS) and IM&NO biomarkers were evaluated in peripheral blood samples. Patients with EDSS ≥3 were older and showed higher homocysteine, uric acid, advanced oxidized protein products (AOPP) and low-density lipoprotein (LDL)-cholesterol and higher rate of metabolic syndrome (MetS), while high-density lipoprotein (HDL)-cholesterol was lower than in patients with EDSS <3; 84.6% of all patients were correctly classified in these EDSS subgroups. We found that 36.3% of the variance in EDSS score was explained by age, Th17/T regulatory (Treg) and LDL/HDL ratios and homocysteine (all positively related) and body mass index (BMI) (inversely related). After adjusting for MS treatment modalities, the effects of the LDL/HDL and zTh17/Treg ratios, homocysteine and age on disability remained, whilst BMI was no longer significant. Moreover, carbonyl proteins were associated with increased disability. In conclusion, the results showed that an inflammatory Th17 profile coupled with age and increased carbonyl proteins were the most important variables associated with high disability followed at a distance by homocysteine, MetS and LDL/HDL ratio. These data underscore that IM&NO pathways play a key role in increased disability in MS patient and may be possible new targets for the treatment of these patients. Moreover, a panel of these laboratory biomarkers may be used to predict the disability in MS.

     

Autologous peripheral blood stem cell transplantation with in vivo T-cell depletion for life threatening refractory systemic lupus erythematosus

We report the first Australian application of autologous haemopoietic stem cell transplantation in a 39-year old woman with severe systemic lupus erythematosus (SLE) and multiple life threatening complications, refractory to conventional therapy including intravenous cyclophosphamide. Our transplant technique, although not unique, differs from most published reports, in which an unmanipulated peripheral stem cell graft was used with in vivo lymphocyte depletion using rabbit antithymocyte globulin (ATG). Successful stem cell mobilization was achieved using granulocytecolony stimulating factor mobilization with methylprednisolone cover, after an initial attempt at mobilization was curtailed by respiratory arrest from upper airway obstruction due to cricoarytenoiditis, requiring tracheostomy. Conditioning regimen for the transplantation was cyclophosphamide 50 mg/kg on days -5 to -2 and rabbit ATG 2.2 mg/kg on days -3 and -2. An unmanipulated autograft was infused, with in vivo T-cell depletion achieved through a further dose of ATG given on day +2 postinfusion. The autologous transplant was well tolerated without fever or other serious complication. At 12 months follow-up post-transplantation, there is an objective evidence of near-complete response with SLE disease activity index scores falling from 40 pretransplant to 2. We conclude that HSCT with unmanipulated peripheral stem cell graft and in vivo lymphocyte depletion with ATG is safe and effective therapy for cyclophosphamide refractory SLE.     

Predictive factors for outcomes after reduced intensity conditioning hematopoietic stem cell transplantation for hematological malignancies: a 10-year retrospective analysis from the Société Française de Greffe de Moelle et de Thérapie Cellulaire

This retrospective study analyzed the impact of demographic and transplantation variables on outcomes of 1108 patients who have undergone allogeneic hematopoietic stem cell transplantation after reduced intensity conditioning (RIC HSCT) for hematological malignancies and were reported to the Société Fran?aise de Greffe de Moelle et de Thérapie Cellulaire registry between November 1994 and December 2004. Only 442 patients (40%) were in complete remission (CR) at time of transplantation. Peripheral blood stem cells were used in the majority of patients (n = 878; 79%), 255 patients received fludarabine and low-dose total body irradiation, while 465 patients (42%) fludarabine and busulfan with rabbit anti-thymocyte globulins (ATG). The impact of demographic and transplant variables was studied on overall (OS) and event-free survival (EFS) in univariate and multivariate analysis. With a median follow-up of 21 months, 3-year probability of OS and EFS was 42% and 30%, respectively, and treatment-related mortality was 15% at 2 years. The multivariate analysis showed a significant negative impact on OS and EFS of the absence of CR status before transplantation; conditioning regimen, including >10 mg/kg ATG; and minor ABO incompatibility. In conclusion, this study highlights the major impact on RIC HSCT outcome of disease status before transplantation, ATG dose and ABO incompatibility.     

Antibodies against Carbonic Anhydrase in Patients with Aplastic Anemia

Background/Aims: Antibodies against carbonic anhydrase (CA) have been detected in patients with an aplastic anemia (AA)-like syndrome after autologous stem cell transplantation. Methods: We analyzed sera of 53 bona fide AA patients before and after treatment with anti-thymocyte globulin (ATG) or bone marrow transplantation for the presence of anti-CA antibodies. Results: Anti-CA antibodies were detected in 20 patients (38%) and were associated with older age at diagnosis of AA. Antibody-positive patients showed poor response to ATG treatment (complete response 14%) and inferior long-term survival (36% at 10 years), when compared to antibody-negative patients (complete response and 10-year survival both 64%). Two thirds of patients with antibodies at diagnosis of AA became antibody negative after treatment with ATG. Clearance of the antibody did not appear to be associated with hematological improvement. Conclusion: Antibodies against CA are detected frequently at diagnosis of AA, and their presence identifies a subset of patients with poor response to immunosuppressive treatment.     

High-dose immunosuppressive therapy for severe systemic sclerosis: initial outcomes

Systemic sclerosis (SSc) is a multisystem disease of presumed autoimmune pathogenesis for which no proven effective treatment exists. High-dose immunosuppressive therapy (HDIT) has been proposed as an investigational treatment for severe autoimmune diseases. Nineteen patients with poor-prognosis SSc underwent HDIT. The median age was 40 years (range, 23-61 years), the median modified Rodnan skin score (a measure of dermal sclerosis) was 31, and the median DLCO was 57%. Conditioning therapy involved 800 cGy total body irradiation (TBI) (+/- lung shielding to approximately 200 cGy), 120 mg/kg cyclophosphamide, and 90 mg/kg equine antithymocyte globulin. CD34-selected granulocyte-colony-stimulating factor-mobilized autologous blood stem cells provided hematopoietic rescue. With median follow-up at 14.7 months, the Kaplan-Meier estimated 2-year survival rate was 79%. Three patients died of treatment complications and one of disease progression. Two of the first 8 patients had fatal regimen-related pulmonary injury, a complication not found among 11 subsequent patients who received lung shielding for TBI. Overall, internal organ functions were stable to slightly worse after HDIT, and 4 patients had progressive or nonresponsive disease. As measured by modified Rodnan skin scores and modified health assessment questionnaire disability index (mHAQ-DI) scores, significant disease responses occurred in 12 of 12 patients evaluated at 1 year after HDIT. In conclusion, though important treatment-related toxicities occurred after HDIT for SSc, modifications of initial approaches appear to reduce treatment risks. Responses in skin and mHAQ-DI scores exceed those reported with other therapies, suggesting that HDIT is a promising new therapy for SSc that should be evaluated in prospective randomized studies.     

T cell depleted stem-cell transplantation for adults with hematologic malignancies: sustained engraftment of HLA-matched related donor grafts without the use of antithymocyte globulin

Antithymocyte globulin (ATG) has been used in allogeneic stem-cell transplantation to prevent graft rejection and graft-versus-host disease (GvHD). Its use, however, has been associated with delayed T-cell reconstitution and prolonged susceptibility to opportunistic infections (OIs) especially in patients undergoing T cell-depleted (TCD) transplantation. Recently, a prospective trial was conducted in 52 adult patients (median age, 47 years) with various hematologic malignancies undergoing TCD transplantation from HLA-matched related donors without the use of ATG. The cytoreductive regimen consisted of hyperfractionated total body irradiation (HFTBI), thiotepa, and fludarabine. The preferred source of the graft was peripheral blood stem cells (PBSCs). No additional graft rejection or GvHD prophylaxis was given. All evaluable patients engrafted without any immune-mediated graft rejections. Disease-free survival (DFS) at 3 years was 61% in all patients, and 70% in patients with standard-risk disease. Acute GvHD was limited to grade 2 in 8% and chronic GvHD in 9% of patients. Life-threatening OIs occurred in 3 of 52 patients and was fatal in 1. This study demonstrates durable engraftment with a low incidence of GvHD despite the lack of ATG, as well as the curative potential of this regimen.     

Adenovirus infection rates in pediatric recipients of alternate donor allogeneic bone marrow transplants receiving either antithymocyte globulin (ATG) or alemtuzumab (Campath)

Infectious complications due to adenovirus are of increasing concern after allogeneic stem cell transplantation. Over the past 4 years, we have modified our conditioning regimens to use alemtuzumab in preference to anti-thymocyte globulin (ATG) for pediatric patients receiving stem cell transplants from alternate donors. Recent reports in adult studies implicate alemtuzumab as a risk factor for adenovirus infection. We therefore evaluated the incidence of adenovirus infection in pediatric patients receiving either ATG or alemtuzumab in their conditioning regimens. Of the 111 patients evaluated, a total of 54 patients received ATG and 57 patients received alemtuzumab. In total, 35/111 (32%) patients were infected by adenovirus, and 9/111 (8%) had adenovirus disease (AD). Adenovirus infection was greater in the alemtuzumab group than the ATG group (23/57 vs 12/54) (P=0.039) and disseminated AD was more frequent in the alemtuzumab group vs the ATG group (8/57 and 1/54 respectively) (P=0.032). The presence of Grade 3-4 graft-versus-host disease was a risk factor for adenovirus infection. Our findings highlight the fact that adenovirus infection is a frequent complication after stem cell transplantation from alternate donors in the pediatric population and that alemtuzumab increases the risk of infection compared to ATG. This work will help in identifying at-risk populations for our upcoming immunotherapy trial using adoptively transferred donor-derived adenovirus-specific cytotoxic T lymphocytes.     

Unrelated bone marrow transplantation in two severe aplastic anemia patients preconditioned with a regimen of cyclophosphamide, antithymocyte globulin, and total body irradiation

We report our experiences with HLA-matched unrelated bonemarrow transplantation combining a preconditioning regimen of cyclophosphamide, antithymocyte globulin (ATG), and total body irradiation for two patients with severe aplastic anemia (SAA) who had already undergone repeated blood transfusions. Short-term methotrexate and cyclosporine were administered for graft-versus-host disease (GVHD) prophylaxis. Both patients achieved rapid engraftment within 3 weeks, furthermore, neither acute nor chronic GVHD developed. Our conditioning regimen appeared to be well-suited for unrelated bone marrow transplantation in heavily transfused SAA patients. However, both patients experienced bouts of fever about 20-30 and 40-50 days after transplantation, and it was difficult to differentiate whether they were affected by acute GVHD, cytomegalovirus (CMV) infections, or serum sickness. Because weakly positive CMV antigenemia was detected, both patients were given ganciclovir. Although their fever did not respond initially, it gradually subsided following the combined administration of prednisolone. These outcomes suggest it is essential that attention be devoted to the potential for serum sickness and the high risk of herpes virus infections, particularly by CMV, following the use of intensive preconditioning regimens that include ATG.