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Abstract: Objective: Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) often demand a single estimate of their prognosis from their treating physician. Little is known about the validity of and the factors influencing these estimates. Patients and methods: We explored physicians'' prognostic estimates (six-point scale from very good to very poor) in a sample of 136 patients participating in a psycho-oncology study. Patients (mean age, 41 years) were followed-up for at least 2 years, and 72 patients died during the follow-up period. Results: Physicians'' estimates were clearly associated with overall survival (univariate Cox regression: hazard ratio=1.51, 95% confidence interval=1.24–1.82). In a multivariate Cox regression model, these estimates were independent predictors for survival in addition to previous treatment (former HSCT) and donor type (related vs. unrelated). Discussion: Physicians on transplant units are able to give a concise prognostic estimate that corresponds to real outcomes. Patients often do not have a sufficient understanding of the risks of their treatment. Obtaining such condensed information instead of a complex prognostic estimate might be easier to understand. For the physician, it might be helpful to reflect his/her individual method of condensing information to be able to give a concise prognosis and to achieve informed consent with the patient. A systematic description of the extensive implicit and explicit experiences regarding objective and subjective data and its respective weight could help to improve the training of future hematologists and should be explored in further studies. [Copyright &y& Elsevier]

We have intensified the conditioning regimen prior to stem cell transplantation in 57 patients with highrisk AML and MDS by treating patients with a [SUP188]Re-labeled anti-CD66 monoclonal antibody. Dosimetry was performed prior to therapy and a favorable dosimetry was observed in all cases. Radioimmunotherapy with the labeled antibody provided a mean of 15.5 Gy of additional radiation to the marrow, the kidney was the normal organ receiving the highest dose of supplemental radiation (mean 7.4 Gy): Radioimmunotherapy was followed by standard full-dose conditioning with total body irradiation (12 Gy) (n = 30) or busulfan (n = 27) and high-dose cyclophosphamide ± thiotepa. Patients subsequently received a T cell depleted allogeneic graft from a HLA-compatible family donor (n = 24), a matched unrelated donor (n = 23) or a haploidentical family donor (n = 6). In four patients, an unmanipulated autologous graft was used. Infusion-related toxicity due to the labeled antibody was minimal and no increase in treatment-related mortality due to the radioimmunoconjugate was observed. Day +30 and day + 100 mortalities were 3 and 7%, respectively, and after a median follow-up of 26 months treatment-related mortality was 30%. Late renal toxicity was observed in 14% of patients. The disease-free survival rate for 44 patients in 1 or 2 CR or in very good PR (< 15% blasts in the marrow at transplant) is 64% with only 8% disease-free survival for those with > 15% blasts in the marrow at transplant. [ABSTRACT FROM AUTHOR]

Disease recurrence following stem cell transplantation (SCT) remains a major problem. Despite the sensitivity of leukaemias to chemotherapy and irradiation, conventional conditioning before SCT is limited by significant organ toxicity. Targeted irradiation of bone marrow and spleen by radioimmunotherapy may provide considerable dose escalation, with limited toxicity to non-target organs. In this study, 27 patients with high-risk or relapsing leukaemia were treated with rhenium-188-labelled CD66a,b,c,e radioimmunoconjugates ([sup 188] Re-mAb) specific for normal bone marrow in addition to conventional conditioning with high-dose chemotherapy and 12 Gy total body irradiation prior to SCT. A mean activity of 10.2±2.1 (range 6.9–15.8) GBq [sup 188] Re-mAb was administered intravenously. Acute side-effects were assessed according to the CTC classification and patient outcome was determined. Mean radiation doses (Gy; range in parentheses) to relevant organs and whole body were as follows: 13.1 (6.5–22) to bone marrow, 11.6 (1.7–31.1) to spleen, 5.0 (2.0–11.7) to liver, 7.0 (2.3–11.6) to kidneys, 0.7 (0.3–1.3) to lungs and 1.4 (0.8–2.1) to the whole body. Stem cells engrafted in all patients within 9–18 days post SCT. Acute organ toxicity of grade II or less was observed. During follow-up for 25.4±5.3 (range 18–34) months, 4/27 (15%) patients died from relapse, and 9/27 (33%) from transplantation-related complications. Fourteen patients (52%) are still alive and in ongoing complete clinical remission. Radioimmunotherapy with the bone marrow-seeking [sup 188] Re-labelled CD66 mAb can double the dose to bone marrow and spleen without undue extramedullary acute organ toxicity, when given in addition to high-dose chemotherapy and 12 Gy TBI before allogeneic SCT. This intensified conditioning regimen may reduce the relapse rate of high-risk leukaemia. [ABSTRACT FROM AUTHOR]

Background: No adequate data exist on the impact of multiple myeloma (MM) with extramedullary disease (EMD) after autograft and maintenance therapy. Methods: We identified 808 patients with newly diagnosed MM who received first autograft, of whom 107 had EMD (83 paraskeletal and 24 organ involvement), and who had been reported to the EBMT registry December 2018. Distribution according to type of involvement was similar between the treatment groups (p =.69). For EMD, 46 (40%) received thalidomide, 59 (51%) lenalidomide, and 11 (10%) bortezomib. Results: The median follow‐up from maintenance start was 44 months. Three‐year progression‐free survival (PFS) was 52% (48%–57%) for no EMD, 56% (44%–69%) for paraskeletal involvement, and 45% (22%–68%) for organ involvement (p =.146). Early PFS (within first year) appeared to be significantly worse for organ involvement (hazard ratio, 3.40), while no significant influence was found after first year from maintenance start. Three‐year overall survival (OS) was 81% (77%–84%), 88% (80%–96%), and 68% (47%–89%; p =.064), respectively. With thalidomide as reference, lenalidomide was significantly associated with better PFS and OS, whereas bortezomib appeared to improve outcome specifically in EMD. Conclusion: Lenalidomide maintenance is standard of care for MM without EMD, whereas extramedullary organ involvement remains a significant risk factor for worse outcome, especially for early events after maintenance start. [ABSTRACT FROM AUTHOR]

Simple Summary: For high-risk patients, particularly young or elderly patients, with diseases of the hematopoietic cells, allogeneic hematopoietic cell transplantation (HCT) is often the only potentially curative treatment option. In preparation, high-dose chemotherapy and, in selected cases, external beam radiotherapy (EBRT) are often used. Especially in high-risk patients, the increased toxicity profile of these forms of treatment can mean treatment failure and even death. With high-dose radioimmunotherapy, the bone marrow can be treated with significantly less stress on the body. For a promising therapy targeting CD66, good results in previous treatments were demonstrated, but there has been increased non-specific accumulation in the liver and kidneys. The objective of this work was to use a recent chelator variant to improve radiolabeling and reduce non-specific accumulation with unaltered bone marrow uptake. In this article, we describe the production and demonstrate the improved distribution of the radiolabeled antibody based on early promising patient data. For patients with acute myeloid leukemia, myelodysplastic syndrome, or acute lymphoblastic leukemia, allogeneic hematopoietic cell transplantation (HCT) is a potentially curative treatment. In addition to standard conditioning regimens for HCT, high-dose radioimmunotherapy (RIT) offers the unique opportunity to selectively deliver a high dose of radiation to the bone marrow while limiting side effects. Modification of a CD66b-specific monoclonal antibody (mAb) with a DTPA-based chelating agent should improve the absorbed dose distribution during therapy. The stability and radioimmunoreactive fraction of the radiolabeled mAbs were determined. Before RIT, all patients underwent dosimetry to determine absorbed doses to bone marrow, kidneys, liver, and spleen. Scans were performed twenty-four hours after therapy for quality control. A radiochemical purity of >95% and acceptable radioimmunoreactivity was achieved. Absorbed organ doses for the liver and kidney were consequently improved compared to reported historical data. All patients tolerated RIT well with no treatment-related acute adverse events. Complete remission could be observed in 4/5 of the patients 3 months after RIT. Two patients developed delayed liver failure unrelated to the radioimmunotherapy. The improved conjugation and radiolabeling procedure resulted in excellent stability, radiochemical purity, and CD66-specific radioimmunoreactivity of 90Y-labeled anti-CD66 mAb. RIT followed by conditioning and HCT was well tolerated. Based on these promising initial data, further prospective studies of [90Y]Y-DTPA-Bn-CHX-A″-anti-CD66-mAb-assisted conditioning in HCT are warranted. [ABSTRACT FROM AUTHOR]

For treatment planning in radioimmunotherapy (RIT), the accurate estimation of time-integrated activity coefficients (TIACs) is essential. To estimate the TIACs in RIT using 90Y-labeled anti-CD66 antibodies, physiologically based pharmacokinetic (PBPK) models are advantageous. Further optimization in predicting therapeutic TIACs may be achieved by including population-specific parameters. Therefore, the aims of this work were (1) to estimate population parameters and (2) to show the effect of these parameters on prediction accuracy of therapeutic biodistributions. To estimate population values, a PBPK model was fitted to pretherapeutic (gamma camera and serum) and therapeutic (serum) measurements simultaneously using the standard two-stage (STS) and iterated two-stage (ITS) algorithms. Including the estimated population values as Bayesian information, the model parameters of each patient were fitted to pretherapeutic data only (simulating therapeutic TIACs). To validate the prediction accuracy of the therapeutic serum curve, the simulated and fitted TIACs were compared. Prediction accuracy expressed as relative deviation (RD) improved from RD=8%±16% to RD=0%±10% for STS and ITS, respectively. The authors demonstrated a method to estimate and apply population values for RIT using a PBPK model and population fitting. For 90Y-labeled anti-CD66 antibodies, the prediction accuracy was substantially improved. [ABSTRACT FROM AUTHOR]

Purpose: Anti-CD45 antibody is predominantly used in the treatment of acute leukemia. CD45 is stably expressed on all leukocytes and their precursors, and therefore the liver and spleen constitute major antigen sinks. Thus, as the red marrow is the target organ, in radioimmunotherapy with anti-CD45 antibody, preloading with unlabeled antibody is a method to increase the absorbed dose to the target cells. In a previous study, a method to individually determine the optimal preload for five patients with acute leukemia was developed. Here, this method is examined and improved using two pretherapeutic measurement series and a refined pharmacokinetic model. Methods: To obtain the biodistribution of 111In-labeled anti-CD45 antibody under different saturation conditions, two measurement series one with and one without preloading were conducted in five patients. For each patient, two physiologically based pharmacokinetic models were fitted to the data and the corrected Akaike information criterion was used to identify the model, which was empirically most supported. The resultant parameter values were compared to values reported in the literature. To individually determine the optimal amount of unlabeled antibody for therapy, computer simulations for preloads ranging from 0 to 60 mg were performed based on the estimated parameters of each patient. The prediction power of the model was assessed by comparing the simulated therapeutic serum curves to the actual 90Y measurements. Results: Visual inspection showed good fits and the adjusted R2 was >0.90 for all patients. All parameters were in a physiologically reasonable range. The relative deviation of the predicted area under the therapeutic serum curve and the measured curve was 15%-33%. The optimal preloading increased the marrow-over-liver selectivity up to 3.9 fold compared to the simulated biodistribution using a standard dose (0.5 mg/kg). Conclusions: The presented method can be used to individually determine the optimal preload and the corresponding residence times in radioimmunotherapy with anti-CD45 antibody. [ABSTRACT FROM AUTHOR]

The Acute Leukemia Working Party (ALWP) of the EBMT assessed the outcome of allogeneic stem cell transplantation (alloSCT) in patients with relapsed/refractory AML (r/rAML) evaluating six sequential conditioning regimens (SR) groups. A total of 2132 patients were included. LFS at 2 years was 28.9%, 33.6%, 35.3%, 20.6%, 24.4%, and 27% for the FLAMSA-TBI4, FLAMSA-Chemo, Mel-Flu-TBI8, Mel-Treo-Flu, Thio-ETO-Cy-Bu2-Flu, and Clo-ARAC-(Bu2/TBI4)-Cy groups, respectively. In patients <55 years of age Mel-Flu-TBI8 had the best LFS, which was statistically significant only in comparison to the Mel-Treo-Flu group, while in patients ≥55 years LFS was best with FLAMSA-Chemo without significant differences compared to FLAMSA-TBI4 and Mel-Flu-TBI8. Furthermore, best NRM rates were obtained with the two FLAMSA regimens groups. Our study suggests that in younger (<55 years) patients a more intense regimen might be used whereas in older (≥55 years) patients the focus might be more on tolerability. [ABSTRACT FROM AUTHOR]

• FLAMSA (fludarabine, Ara-C, and amsacrine) sequential chemotherapy followed by total body irradiation (TBI)-based reduced-intensity conditioning (RIC) and myeloablative conditioning (MAC) led to similar transplantation outcomes in relapsed/refractory active acute myeloid leukemia. • FLAMSA sequential chemotherapy followed by TBI-free RIC was associated with lower nonrelapse mortality resulting in increased overall survival. • There were no significant differences in relapse incidence between FLAMSA sequential chemotherapy followed by RIC and MAC. The use of myeloablative conditioning (MAC) in the setting of active relapsed/refractory (R/R) acute myeloid leukemia (AML) has been hindered by high historical rates of nonrelapse mortality (NRM). FLAMSA (fludarabine, Ara-C, and amsacrine) chemotherapy (CT) followed by reduced-intensity conditioning (RIC) has been proposed as an effective and potentially safer alternative in this scenario. As improvements in supportive care have contributed to decreasing NRM rates after MAC, a comparative reassessment of these two strategies was performed. This was a registry-based analysis by the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation. Eligibility criteria included age 18 to 50 years, primary refractory, first or second relapsed active AML, first allogeneic stem cell transplantation from a matched sibling donor (MSD) or an unrelated donor (UD) performed between 2005 and 2018, MAC or FLAMSA-RIC. A total of 1018 patients were included. The median patient age was 39 years (range, 18 to 50). Two hundred and fifty-eight patients received busulfan (Bu)/cyclophosphamide (Cy), 314 received Cy/total body irradiation (TBI), 318 received FLAMSA-TBI, and 128 received FLAMSA-CT. The median duration of follow-up was 50 months. In univariate analysis, the 2-year relapse incidence (RI) (54%; 95% confidence interval (CI), 50%-57%), leukemia-free survival (LFS) (30%; 95% CI, 27%-33%), and refined graft-versus-host disease-free, relapse-free survival (GRFS) (21%; 95% CI, 18%-24%) were not significantly different between cohorts. Lower 2-year NRM was observed in the FLAMSA-CT group (7% versus 16% in Bu/Cy, 19% in Cy/TBI, and 18% in FLAMSA-TBI; P =.04), as well as increased 2-year overall survival (OS) (50% versus 33% in Bu/Cy, 34% in Cy/TBI, and 36% in FLAMSA-TBI; P =.03). These results were maintained in the multivariate analysis (hazard ratio [HR] for NRM:.40, P =.01; HR for OS:.65, P =.01; Bu/Cy as reference). These data suggest that FLAMSA-CT may be a preferred conditioning regimen in patients with active R/R AML due to lower NRM. Yet, the high relapse rates observed in our analyses emphasize the need for novel therapeutic strategies in this clinical setting. [ABSTRACT FROM AUTHOR]

Introduction: Respiratory viral infections are a major cause of morbidity and mortality among stem cell transplant recipients. While there is a substantial amount of information on prognostic factors and response to ribavirin therapy is available for RSV infections, this information is largely lacking for hMPV. Patients and methods: In total, 71 patients were included in this study: 47 patients with RSV and 24 with hMPV. Forty‐one patients presented as an upper respiratory tract infection (URTI) and 30 as a primary lower respiratory tract infection (LRTI). Patients were stratified as per ISI criteria into low‐, moderate‐, and high‐risk groups. Twenty‐two patients in the URTI cohort received treatment with ribavirin (mainly oral), and 19 patients received no antiviral therapy. The decision for antiviral treatment was at the discretion of the attending physician. All 30 patients with primary LRTI and 10 patients with secondary LRTI were treated with ribavirin, 95% with the intravenous formulation. 45% of these patients received additional treatment with intravenous immunoglobulins. The viral load was assessed indirectly by using the CT value of the RT‐PCR. Results: In the cohort, as whole 11.5% suffered a virus‐associated death, 5% in the URTI group, and 20% in the LRTI group. Sixty‐day mortality was significantly higher in the ISI high‐risk group (log‐rank P =.05). Mortality was independent of the type of virus (P =.817). Respiratory failure with an indication for mechanical ventilation developed in 11.5%, this risk was independent of the type of virus. Progression from URTI to LRTI was observed in 24% of cases with a significantly higher risk (75%) in the ISI high group (log‐rank P =.001). In the ISI high‐risk group, treatment with ribavirin significantly reduced the risk of progression (log‐rank P <.001). Neither the type of virus nor the viral load in the nasopharyngeal swab impacted the risk of progression (P =.529 and P =.141, respectively). The detection of co‐pathogens in the BAL fluid was borderline significant for mortality (P =.07). Conclusions: We could detect no differences between RSV and hMPV with respect to progression to LRTI, risk of respiratory failure or need for mechanical ventilation and virus‐associated death. The ISI index is of predictive value in hMPV patients with a high ISI score and treatment with oral ribavirin has an equivalent protective effect in RSV and hMPV patients. Treatment of LRTI with intravenous ribavirin results in a similar outcome in RSV‐ and hMPV‐infected patients. We could not detect any benefit of adjunctive treatment with immunoglobulins in both primary and secondary LRTI. No role of viral load as an independent prognostic marker could be detected either for progression to LRTI or death. [ABSTRACT FROM AUTHOR]

Summary: Myeloproliferative Neoplasm (MPN), unclassifiable (MPN‐U) is a heterogeneous disease with regards to both clinical phenotype and disease course. Patients may initially be asymptomatic or present with leucocytosis or thrombocytosis, anaemia, progressive splenomegaly, constitutional symptom, thromboses or accelerated/blastic phase disease. Treatment strategies are variable and there are no widely accepted consensus management guidelines for MNU‐U. Allogeneic Haematopoietic Cell Transplantation (allo‐HCT) remains the only curative strategy yet outcomes, to date, are not well defined. We hereby report on the largest retrospective study of patients with MPN‐U undergoing allo‐HCT, highlighting the potentially curative role and providing clinicians with robust engraftment, GvHD and outcome data to facilitate patient discussion. [ABSTRACT FROM AUTHOR]

Allogeneic stem cell transplantation (allo-SCT) is the preferred curative treatment for several hematological malignancies. The efficacy of allo-SCT depends on the graft-versus-leukemia (GvL) effect. However, the prognosis of patients with relapsed acute myeloid leukemia (AML) following allo-SCT is poor. Donor lymphocyte infusion (DLI) is utilized after allo-SCT in this setting to prevent relapse, to prolong progression free survival, to establish full donor chimerism and to restore the GvL effect in patients with hematological malignancies. Thus, there are different options for the administration of DLI in AML patients. DLI is currently used prophylactically and in the setting of an overt relapse. In addition, in the minimal residual disease (MRD) setting, DLI may be a possibility to improve overall survival. However, DLI might increase the risk of severe life-threatening complications such as graft-versus-host disease (GvHD) as well as severe infections. The transfusion of lymphocytes has been tested not only for the treatment of hematological malignancies but also chronic infections. In this context, manipulated DLI in a prophylactic or therapeutic approach are an option, e.g., virus-specific DLI using different selection methods or antigen-specific DLI such as peptide-specific CD8+ cytotoxic T lymphocytes (CTLs). In addition, T cells are also genetically engineered, using both chimeric antigen receptor (CAR) genetically modified T cells and T cell receptor (TCR) genetically modified T cells. T cell therapies in general have the potential to enhance antitumor immunity, augment vaccine efficacy, and limit graft-versus-host disease after allo-SCT. The focus of this review is to discuss the different strategies to use donor lymphocytes after allo-SCT. Our objective is to give an insight into the functional effects of DLI on immunogenic antigen recognition for a better understanding of the mechanisms of DLI. To ultimately increase the GvL potency without raising the risk of GvHD at the same time. [ABSTRACT FROM AUTHOR]

Patients with hematological malignancies undergoing intensive chemotherapy or due to their underlying disease often suffer from serious infections during neutropenia. The majority of infections were caused by fungi in 14 patients (74%), bacterial infections were diagnosed in 5 patients (26%). Nonetheless, our data provide first insights into the benefits of GTs supporting selected neutropenic patients with uncontrolled infection, hence heightening chances of these severely ill patients of reaching HCT. Efficacy of transfusion with granulocytes from G-CSF/dexamethasone-treated donors in neutropenic patients with infection. [Extracted from the article]

Background and objectives: Mobilization of CD34+ cells by stimulation with G‐CSF shows considerable variation across stem cell donors. Upfront prediction of CD34+ cell counts in peripheral blood based on easily available steady‐state parameters would be helpful for the planning of apheresis and stem cell transplantation. Commonly accepted steady‐state predictors for the mobilization are gender, body mass index and platelet count. The aim of the study was the identification of novel predictors that might influence mobilization efficacy and to create a model for the prediction of stem cell mobilization. Methods: A total of 333 healthy stem cell donors who donated peripheral stem cells in our institution were retrospectively analysed. All available data before stem cell mobilization with G‐CSF were included in the database. Primary end‐point was CD34+ cell count before the first apheresis. Results: In this cohort cholinesterase, differential blood cell counts including platelets, gender and body mass index were significantly correlated with CD34+ cell count. G‐CSF dose per lean body weight showed a significant correlation with mobilization efficacy in women but not in men. A multivariate analysis identified gender, cholinesterase and platelet and red cell count as main predictors of mobilization. Red cell count showed a strong gender dependence, with higher predictive value in females. Conclusion: The counts of eosinophils, platelets, red cells, cholinesterase and gender are the most important predictors of CD34+ cell mobilization in our deduced models. The red cell count as a predictor for mobilization showed a differential gender dependence. [ABSTRACT FROM AUTHOR]

Purpose: Despite improved treatment options, multiple myeloma (MM) remains an incurable disease. The aim of this study was to investigate the prognostic value of positron emission tomography/computed tomography (PET/CT) using 18F-2’-deoxy-2’-fluorodeoxyglucose ([18F]FDG) in MM patients shortly before and ~100 days after allogeneic hematopoietic cell transplantation (allo-HCT).Methods: In this retrospective analysis, we evaluated [18F]FDG-PET/CT-scans of 45 heavily pre-treated MM patients before and 27 patients after scheduled allo-HCT. All scans were qualitatively and semi-quantitatively assessed for the presence of active disease. Serological response was recorded according to International Myeloma Working Group (IMWG) criteria. Progression-free (PFS) and overall survival (OS) were correlated with different PET/CT-derived parameters, such as presence, number and maximum standardized uptake value (SUVmax) of focal myeloma lesions. The impact of extramedullary disease on patient outcome was also assessed.Results: PET/CT negativity -prior to or following allo-HCT- was a favorable prognostic factor for progression-free and overall survival (both, PFS and OS: pre-HSCT p < 0.001, post-HCT p < 0.005). High FDG-uptake (SUVmax > 6.5) revealed a significantly shortened survival compared to patients with a lower SUVmax (<6.5) (OS, 5.0 ± 1.1 m vs. not reached - longest 122.0 m; p < 0.001). Moreover, our data prove that a higher number (>3) of focal lesions (pre-HCT: both PFS and OS: p < 0.001; post-HCT PFS: p < 0.001, OS: p = 0.139) as well as the presence of extramedullary disease serve as adverse prognostic factors prior to and after allo-HCT. At response assessment after allo-HCT, [18F]FDG-PET/CT had a complementary value in prognostication in addition to IMWG criteria alone.Conclusion: [18F]FDG-PET/CT before and shortly after allogeneic HCT is a powerful predictor for progression-free and overall survival in MM patients. [ABSTRACT FROM AUTHOR]

Introduction: Involvement of the central nervous system in patients with multiple myeloma is a rare event. We evaluated the diagnostic workup and prognosis of patients with leptomeningeal myelomatosis (LMM). Methods: Between April 2005 and April 2016, we identified 16 cases with LMM. The involvement was diagnosed by magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) cytology as well as flow cytometry. Fluorescence in situ hybridization (FISH) was used in 8/16 cases. In 1 case, genome-wide screening for genetic alterations using single-nucleotide polymorphism (SNP) array analysis was performed. Results: The median time from initial diagnosis until the occurrence of LMM was 434 days. At diagnosis, the median age was 60 years. The median cell count was 21/µL (range 1–1,333/µL). All CSF samples showed malignant pleocytosis, confirmed by flow cytometry in 12/16 patients. FISH revealed high-risk features in the majority of samples. Treatment for LMM consisted of intrathecal chemotherapy and radiation therapy. Genome-wide screening assays revealed different subclones. The outcome was dismal with a median overall survival after the diagnosis of LMM of 82 days. Conclusion: By combining several technical procedures, it is possible to identify most patients with LMM. Management of affected patients is challenging and the survival short after a diagnosis of LMM. [ABSTRACT FROM AUTHOR]

Background: T-cell-depleted, haploidentical transplantations (haplos) are commonly offered to patients who have high-risk, acute leukemia in the absence of a human leukocyte antigen (HLA) full-matched donor.Methods: To determine the effect of transplantation period, the authors divided 308 adults with de novo, acute leukemia who underwent T-cell-depleted haplo from 2005 to 2015 into 2 groups, according the year in which they underwent transplantation (2005-2011 [n = 191] and 2012-2015 [n = 117]).Results: The median age was 41 years in patients who underwent transplantation before 2012 and 46 years in those who underwent transplantation after 2012 (P = .04). Most patients had acute myeloid leukemia (75% vs 69%; P = .26) and were in first complete remission (CR1) (55% vs 64%; P = .12) at the time of transplantation. The cumulative incidence of grade 2, 3, and 4 acute graft-versus-host disease (GvHD) and chronic GvHD were not different between the 2 groups (acute GvHD: 20% vs 22% cumulative incidence in patients who underwent haplo before and after 2012, respectively [P = .67]; chronic GvHD: 19% vs 11% cumulative incidence, respectively; P = .12]. The 2-year relapse incidence was 20%, the nonrelapse mortality (NRM) rate was 48%, and no difference was observed over time (21% vs 19% [P = .72] and 54% vs 38% [P = .11] for patients who underwent haplo before and after 2012, respectively). The main cause of NRM was infection. Haplo after 2012 (hazard ratio [HR], 0.57; P = .01), younger age (HR, 0.82; P = .02), and receipt of a reduced-intensity conditioning (RIC) regimen (HR, 0.53; P = .01) were independently associated with lower NRM. The 2-year overall survival rate was 36% and improved after 2012 (29% vs 47% before 2012; P = .02); and it was higher for patients who underwent transplantation in CR1 (41% vs 29%; P = .01). In multivariate analysis, haplo after 2012 (HR, 0.54; P = .003) and receipt of a RIC regimen (HR, 0.54; P = .005) were independently associated with better overall survival. Similarly, leukemia-free survival and GvHD-free/relapse-free survival (GRFS) improved over time: the leukemia-free survival rate was 31% (25% vs 43% in the groups who underwent transplantation before and after 2012, respectively; P = .05), and the GRFS rate was 24% (19% vs 34%, respectively; P = .09). In addition, leukemia-free survival and GRFS improved among patients who received a RIC regimen.Conclusions: The outcome of patients with acute leukemia who underwent T-cell-depleted haplo has improved over time. Cancer 2018;124:2142-50. © 2018 American Cancer Society. [ABSTRACT FROM AUTHOR]

We report the results of a single-center analysis of a cohort of 39 patients treated between 1997 and 2016 for transplantion-associated thrombotic microangiopathy. We evaluated 2 subgroups of patients: 24 patients treated between 1997 and 2014 who received conventional therapy and 15 patients treated with the complement-inhibiting monoclonal antibody eculizumab between 2014 and 2016. The conventional therapy group was treated predominantly with defibrotide alone or in combination with plasmapheresis or rituximab. Despite an initial response rate of 61%, only 4 patients (16%) were long-term survivors, 2 of whom had a low-risk thrombotic microangiopathy without multiorgan damage. Progression of thrombotic micorangiopathy and bacterial/fungal infections contributed equally to treatment failure. The overall response rate in the eculizumab group was significantly higher, at 93%. In addition, we were able to stop eculizumab treatment in 5 patients (33%), all of whom had high-risk thrombotic microangiopathy, due to sustained recovery. Despite the very good response in the eculizumab-treated group, we did not observe a significant improved overall survival, due primarily to a high rate of infection-related mortality (70%). Therefore, further studies are needed to identify the optimal therapeutic management approach for transplantation-associated thrombotic microangiopathy to improve its dismal outcome. [ABSTRACT FROM AUTHOR]

The article reports on a study which investigated the impact of telomere length on the outcome of allogeneic stem cell transplantation (SCT) for patients with poor risk chronic lymphocytic leukaemia (CLL) based on the German CLL3X trial which included 100 patients. Topics covered include association of telomere length with clinical characteristics, and analysis of telomere length using quantitative polymerase chain reaction.

Background: Primary refractory acute myeloid leukemia (PRF-AML) is associated with a dismal prognosis. Allogeneic stem cell transplantation (HSCT) in active disease is an alternative therapeutic strategy. The increased availability of unrelated donors together with the significant reduction in transplant-related mortality in recent years have opened the possibility for transplantation to a larger number of patients with PRF-AML. Moreover, transplant from unrelated donors may be associated with stronger graft-mediated anti-leukemic effect in comparison to transplantations from HLA-matched sibling donor, which may be of importance in the setting of PRF-AML. Methods: The current study aimed to address the issue of HSCT for PRF-AML and to compare the outcomes of HSCT from matched sibling donors (n = 660) versus unrelated donors (n = 381), for patients with PRF-AML between 2000 and 2013. The Kaplan-Meier estimator, the cumulative incidence function, and Cox proportional hazards regression models were used where appropriate. Results: HSCT provide patients with PRF-AML a 2-year leukemia-free survival and overall survival of about 25 and 30%, respectively. In multivariate analysis, two predictive factors, cytogenetics and time from diagnosis to transplant, were associated with lower leukemia-free survival, whereas Karnofsky performance status at transplant ⩾90% was associated with better leukemia-free survival (LFS). Concerning relapse incidence, cytogenetics and time from diagnosis to transplant were associated with increased relapse. Reduced intensity conditioning regimen was the only factor associated with lower non-relapse mortality. Conclusions: HSCT was able to rescue about one quarter of the patients with PRF-AML. The donor type did not have any impact on PRF patient's outcomes. In contrast, time to transplant was a major prognostic factor for LFS. For patients with PRF-AML who do not have a matched sibling donor, HSCT from an unrelated donor is a suitable option and therefore, initiation of an early search for allocating a suitable donor is indicated. [ABSTRACT FROM AUTHOR]

Natural Killer cells (NK) are lymphocytes with the potential to recognize and lyse cells which escaped T-cell mediated lysis due to their aberrant HLA expression profiles. Killer cell immunoglobulin-like receptors (KIR) influence NK-cell activity by mediation of activating or inhibitory signals upon interaction with HLA-C (C1, C2) ligands. Therefore, absence of ligands for donor inhibitory KIRs following hematopoietic stem cell transplantation (HSCT) may have an influence on its outcome. Previous studies showed that C1 negative patients have a decreased HSCT outcome. Our study, based on a cohort of 200 C1-negative patients, confirmed these findings for the endpoints: overall survival (OS: HR = 1.41, CI = 1.14–1.74, p = 0.0012), disease free survival (DFS: HR = 1.27, CI = 1.05–1.53, p = 0.015), treatment related mortality (TRM: HR = 1.41, CI = 1.01–1.96, p = 0.04), and relapse incidence (RI: HR = 1.33, CI = 1.01–1.75, p = 0.04) all being inferior when compared to C1-positive patients (n = 1246). Subsequent analysis showed that these findings applied for patients with myeloid malignancies but not for patients with lymphoproliferative diseases (OS: myeloid: HR = 1.51, CI = 1.15–1.99, p = 0.003; lymphoblastic: HR = 1.26, CI = 0.91–1.75, p = 0.16; DFS: myeloid: HR = 1.31, CI = 1.01–1.70, p = 0.04; lymphoblastic: HR = 1.21, CI = 0.90–1.61, p = 0.21; RI: myeloid: HR = 1.31, CI = 1.01–1.70, p = 0.04; lymphoblastic: HR = 1.21, CI = 0.90–1.61, p = 0.21). Interestingly, within the C1-negative patient group, transplantation with KIR2DS2 resulted in better OS (9/10 matched: HR = 0.24, CI = 0.08–0.67, p = 0.007) as well as DFS (9/10 matched: HR = 0,26, CI = 0.11–0.60, p = 0.002), and transplantation with KIR2DS1 positive donors was associated with a decreased RI (HR = 0.30, CI = 0.13–0.69, p = 0.005). TRM was increased when the donor was positive for KIR2DS1 (HR = 2.61, CI = 1.26–5.41, p = 0.001). Our findings suggest that inclusion of KIR2DS1/2/5 and KIR3DS1-genotyping in the unrelated donor search algorithm of C1-ligand negative patients with myeloid malignancies may prove to be of clinical relevance. [ABSTRACT FROM AUTHOR]

Major histocompatibility complex class I polypeptide-related sequence A (MICA) is a highly polymorphic ligand of the activating NKG2D receptor on natural killer (NK) cells, γδ-T cells, and NKT cells. MICA incompatibilities have been associated with an increased graft-versus-host disease (GVHD) incidence, and the MICA-129 (met/val) dimorphism has been shown to influence NKG2D signaling in unrelated hematopoietic stem cell transplantation (uHSCT). We investigated the effect of MICA matching on survival after uHSCT. We sequenced 2172 patients and their respective donors for MICA. All patients and donors were high-resolution HLA-typed and matched for 10/10 (n = 1379), 9/10 (n = 636), or 8/10 (n = 157) HLA alleles. Within each HLA match group, cases matched and mismatched for MICA and MICA-129 were analyzed for the end points overall survival (OS), disease-free survival (DFS), nonrelapse mortality (NRM), relapse-incidence (RI), and GVHD. Mismatches at the MICA locus as well as MICA-129 increased with the number of HLA mismatches (MICA mismatched 10/10, 9.2% [n=127]; 9/10, 22.3% [n=142]; 8/10, 38.2% [n=60]; MICA-129 mismatched 10/10, 3.9% [n=54]; 9/10, 10.2% [n=65]; 8/10, 17.2% [n=27]). Adverse OS was observed in the 10/10 match group if MICA-129 was mismatched (10/10, hazard ratio [HR], 1.77; confidence interval [CI], 1.22-2.57; P5.003). MICA-129 mismatches correlated with a significantly worse outcome for DFS in the 10/10 HLA match group (HR, 1.77; CI, 1.26-2.50; P 5 .001). Higher rates of aGVHD were seen in MICA-129 mismatched cases. Our results indicate that MICA-129 matching is relevant in uHSCT. Prospective typing of patients and donors in unrelated donor search may identify mismatches for MICA-129, and compatible donor selection may improve outcome for this small but high-risk subgroup. [ABSTRACT FROM AUTHOR]

Background: Myeloablative (MAC) and reduced-intensity conditioning (RIC) are established approaches for allogeneic stem cell transplantation (SCT) in acute myeloid leukemia (AML). Most deaths after MAC occur within the first 2 years after SCT, while patients surviving leukemia-free for 2 years can expect a favorable long-term outcome. However, there is paucity of data on the long-term outcome (beyond 10 years) and the pattern of late events following RIC due to the relative recent introduction of this approach. Methods: We analyzed long-term outcomes in a cohort of 1423 AML patients, age =50 years, after SCT from HLA-matched siblings, during the years 1997-2005, median follow-up 8.3 years (0.1-17). Results: The 10-year leukemia-free survival (LFS) was 31 % (95CI, 27-35) and 32 % (28-35) after MAC and RIC, respectively (P = 0.57). The 10-year GVHD/ relapse-free survival (GRFS), a surrogate for quality of life was 22 % (18-25) and 21 % (18-24), respectively (P = 0.79). The 10-year non-relapse mortality (NRM) was higher and relapse rate was lower after MAC, throughout the early and late post-transplant course. The 10-year LFS among 584 patients surviving leukemia-free 2 years after SCT was 71 % (65-76) and 73 % (67-78) after MAC and RIC, respectively (P = 0.76). Advanced leukemia at SCT was the major predictor of LFS subsequent to the 2-year landmark. Relapse was the major cause of late death after both regimens; however, NRM and in particular chronic graft-versus-host disease and second cancers were more common causes of late death after MAC. Conclusions: Long-term LFS and GRFS are similar after RIC and MAC. Most events after RIC or MAC occur within the first 2 years after SCT. Patients who are leukemia-free 2 years after SCT can expect similar good subsequent outcome after both approaches. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) relapse after allogeneic hematopoietic cell transplantation (alloHCT) remains a major therapeutic challenge. We studied outcomes of 1788 AML patients relapsing after alloHCT (1990 to 2010) during first or second complete remission (CR) to identify factors associated with longer postrelapse survival. Median time to post-HCT relapse was 7 months (range, 1 to 177). At relapse, 1231 patients (69%) received intensive therapy, including chemotherapy alone (n = 660), donor lymphocyte infusion (DLI) ± chemotherapy (n = 202), or second alloHCT ± chemotherapy ± DLI (n = 369), with subsequent CR rates of 29%. Median follow-up after relapse was 39 months (range, <1 to 193). Survival for all patients was 23% at 1 year after relapse; however, 3-year overall survival correlated with time from HCT to relapse (4% for relapse during the 1- to 6-month period, 12% during the 6-month to 2-year period, 26% during the 2- to 3-year period, and 38% for ≥3 years). In multivariable analysis, lower mortality was significantly associated with longer time from alloHCT to relapse (relative risk, .55 for 6 months to 2 years; relative risk, .39 for 2 to 3 years; and relative risk, .28 for ≥3 years; P < .0001) and a first HCT using reduced-intensity conditioning (relative risk, .77; 95% confidence interval [CI], .66 to .88; P = .0002). In contrast, inferior survival was associated with age >40 years (relative risk, 1.42; 95% CI, 1.24 to 1.64; P < .0001), active graft-versus-host disease at relapse (relative risk, 1.25; 95% CI, 1.13 to 1.39; P < .0001), adverse cytogenetics (relative risk, 1.37; 95% CI, 1.09 to 1.71; P = .0062), mismatched unrelated donor (relative risk, 1.61; 95% CI, 1.22 to 2.13; P = .0008), and use of cord blood for first HCT (relative risk, 1.23; 95% CI, 1.06 to 1.42; P = .0078). AML relapse after alloHCT predicted poor survival; however, patients who relapsed ≥6 months after their initial alloHCT had better survival and may benefit from intensive therapy, such as second alloHCT ± DLI. [ABSTRACT FROM AUTHOR]

Purpose: In the two consecutive German studies III and IIIA on chronic myeloid leukemia, between 1995 and 2004, 781 patients were randomized to receive either allogeneic hematopoietic stem cell transplantation with a related donor or continued drug treatment. Despite comparable transplantation protocols and most centers participating in both studies, the post-transplant survival probabilities for patients transplanted in first chronic phase were significantly higher in study IIIA (144 patients) than in study III (113 patients). Prior to the decision on a combined analysis of both studies, reasons for this discrepancy had to be investigated. Methods: The Cox proportional hazard cure model was used to identify prognostic factors for post-transplant survival. Results: Donor-recipient matching for human leukocyte antigen, patient age, time between diagnosis and transplantation, and calendar time showed a significant influence on survival and/or the incidence of cure. Added as a further factor, affiliation to study IIIA had no significant impact any longer. Conclusions: Discrepancies in influential prognostic factors explained the different post-transplant survival probabilities between the studies. The significance of calendar time suggests a lack of consistency of transplantation practice over time. Accordingly, the prerequisite for a common assessment of overall survival in the two randomized transplantation arms was not met. Moreover, our analyses provide an independent validation of established prognostic factors and their cutoffs. The statistical approach in investigating and modeling potential prognostic factors for survival sets an example for the examination of studies with unexpected outcome differences in concurrent treatment arms. [ABSTRACT FROM AUTHOR]

Relapse is one of the main problems which can occur following allogeneic transplantation for haematological malignancies. In this situation the enhancement of the graft-versus-leukaemia effect by transfusion of donor buffy coats with or without cytokines may lead to complete remission especially in myeloid leukaemias. FISH (fluorescence in situ hybridization) is a sensitive method to monitor chimaerism in gender-different transplantation. We report a case of successful buffy coat transfer therapy > 9 years after bone marrow transplanation. This is the longest interval reported, to our knowledge, between transplantation to relapse, which was treated by adoptive immunotherapy. Complete donor chimaerism was confirmed by FISH. [ABSTRACT FROM AUTHOR]

BACKGROUND The objective of the current study was to investigate the role of postremission consolidation chemotherapy before reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (alloSCT) for patients with acute myeloid leukemia (AML) in first complete remission (CR1). METHODS Of the 789 consecutive patients with AML in CR1 who underwent RIC alloSCT from a human leukocyte antigen-matched sibling or matched unrelated donor peripheral stem cell grafts between 2001 and 2010, 591 patients received at least 1 cycle of consolidation chemotherapy and 198 patients did not receive any consolidation chemotherapy before alloSCT. To minimize inherent survival bias in favor of patients who underwent transplant long after achieving CR1, the study focused on 373 patients who underwent transplant within the median time frame between achievement of CR1 and alloSCT (3 months for patients who underwent alloSCT from matched siblings and 4 months for patients who underwent alloSCT from matched unrelated donors). In this subgroup, 151 patients did not receive any consolidation chemotherapy and 222 patients received ≥ 1 consolidation chemotherapy cycle. RESULTS With a median follow-up of 36 months (range, 2 months-135 months), the 3-year cumulative recurrence incidence (RI) was not significantly different between the groups (36% ± 4% for the group treated without consolidation chemotherapy vs 38% ± 3% for patients who received consolidation chemotherapy; P = .89). In addition, leukemia-free survival was similar between the groups (45% ± 4% and 47% ± 3%, respectively; P = .41). Dose intensity of cytarabine given during consolidation chemotherapy appeared to have no influence on RI. On multivariate analysis, pretransplant consolidation (≥ 1 cycle vs 0 cycles) was found to have no significant impact on RI (hazards ratio, 1.29; 95% confidence interval, 0.84-1.97 [ P = .24]) or leukemia-free survival (hazards ratio, 1.00; 95% confidence interval, 0.71-1.42 [ P = .99]). CONCLUSIONS The data from the current study suggest no apparent advantage for postremission consolidation chemotherapy before RIC alloSCT, provided a donor is readily available. Cancer 2014;120:855-863. © 2013 American Cancer Society. [ABSTRACT FROM AUTHOR]

To validate current donor selection strategies based on previous international studies, we retrospectively analyzed 2646 transplantations performed for hematologic malignancies in 28 German transplant centers. Donors and recipients were high resolution typed for HLA-A, -B, -C, -DRB1, and -DQB1. The highest mortality in overall survival analysis was seen for HLA-A, -B, and DRB1 mismatches. HLA-DQB1 mismatched cases showed a trend toward higher mortality, mostly due to HLA-DQB1 antigen disparities. HLA incompatibilities at >1 locus showed additive detrimental effects. HLA mismatching had no significant effect on relapse incidence and primary graft failure. Graft source had no impact on survival end points, neither in univariate nor in multivariate analysis. Higher patient age, advanced disease, transplantations before 2004, patient C2C2 killer cell immunoglobulin-like receptor (KIR)-ligand phenotype, and unavailability of a national donor adversely influenced outcomes in multivariate analysis. Our study confirms the association of HLA-A, -B, -C, and -DRB1 incompatibilities with adverse outcome in hematopoietic stem cell transplantation (HSCT). The relevance of HLA-DQB1 disparities in single mismatched transplantations remains unclear. Similar hazard ratios for allele and antigen mismatches (possibly with an exception for HLA-DQB1) highlight the importance of allele level typing and matching in HSCT. The number of incompatibilities and their type significantly impact survival. [ABSTRACT FROM AUTHOR]

The purpose of this analysis was to provide 6-year follow-up of the CLL3X trial, which studied reduced-intensity allogeneic hematopoietic stem cell transplantation (HSCT) in patients with poor-risk chronic lymphocytic leukemia (CLL), and to investigate the effect of TP53, SF3B1, and NOTCH1 mutations on HSCT outcome. For 90 allografted patients, 6-year overall survival (OS) was 58% and 6-year event-free survival (EFS) was 38%. TP53, SF3B1, and NOTCH1 mutations were found in 30%, 26%, and 14% of the trial population, respectively. By univariate and multivariate analyses, the mutational status of the TP53, SF3B1, and NOTCH1 genes had no significant effect on OS and EFS. Studies of minimal residual disease confirmed durability of CLL eradication in mutated patients. We conclude that HSCT can provide long-term disease control in patients with poor-risk CLL independent of the presence of TP53, SF3B1, and NOTCH1 mutations. The trial has been registered at the US National Cancer Institute as #EU-20554, NCT00281983. [ABSTRACT FROM AUTHOR]

Reduced-intensity conditioning allogeneic stem cell transplant (RIC-alloSCT) is being increasingly used for patients with acute myelogenous leukemia (AML) with comorbidities. Few published data are currently available regarding for the use of peripheral blood stem cells (PBSCs) compared to bone marrow (BM) in the RIC-alloSCT using unrelated donors (URDs). This retrospective report compared the outcomes of PBSC versus BM RIC-alloSCT. Between 2000 and 2007, 602 patients with AML in complete remission (CR) underwent RIC-alloSCT from URDs with PBSC (508) or BM (94) grafts. Recipient''s age was higher in the PBSC versus BM groups 57 (range, 17-77 years) and 51 (range, 17-76 years), respectively (P < .0001). Leukemia features and disease status at RIC-alloSCT were also comparable between the PBSC versus BM groups. Engraftment was achieved in 97% and 96% with BM versus peripheral blood (PB), respectively. Acute graft-versus-host disease (aGVHD) grade >II was significantly higher in the PBSC group: 27% versus 12% in the BM group (P < .002). Similarly, chronic graft-versus-host disease (cGVHD; at 2 years) was somewhat higher in the PBSC group with 43% ± 3% versus 35% ± 6% in the BM group, respectively (P = .04). The 2-year probabilities of leukemia-free survival (LFS) were 46% ± 3% for the PBSC group in comparison to 43% ± 6% for the BM transplant group (P = NS), whereas relapse incidence was significantly higher in the BM versus the PB transplant group: 46% ± 6% versus 32% ± 3%, respectively (P = .014). Non-relapse mortality (NRM) was significantly higher for the PBSC versus the BM group: 28% ± 2% versus 13% ± 4%, respectively (P = .004). In multivariate analysis, after adjustment for differences between both groups, the PBSC group was associated with a higher incidence of aGVHD (grade II-IV; hazard ratio [HR] = 2.33; P = .06), higher NRM (HR = 2.3; P = .015), and a decreased relapse incidence (HR, 0.61; P = .02) with no statistical difference of LFS between the 2 groups (P = .88). In conclusion, our results indicate significantly higher incidence of aGVHD and NRM and a lower incidence of relapse but not statistically different LFS comparing unrelated PBSC to BM grafts after RIC-alloSCT. [Copyright &y& Elsevier]

We compared the outcomes of patients age 60-70 years with acute myelogenous leukemia receiving reduced-intensity allogeneic hematopoietic cell transplantation (HCT) in first remission (CR1) reported to the Center for International Blood and Marrow Research (n = 94) with the outcomes in patients treated with induction and postremission chemotherapy on Cancer and Leukemia Group B protocols (n = 96). All patients included had been in CR1 for at least 4 months. The HCT recipients were slightly younger than the chemotherapy patients (median age, 63 years vs 65 years; P < .001), but there were no significant between-group differences in the proportion with therapy-related leukemia or in different cytogenetic risk groups. Time from diagnosis to CR1 was longer for the HCT recipients (median, 44 days vs 38 days; P = .031). Allogeneic HCT was associated with significantly lower risk of relapse (32% vs 81% at 3 years; P < .001), higher nonrelapse mortality (36% vs 4% at 3 years; P < .001), and longer leukemia-free survival (32% vs 15% at 3 years; P = .001). Although overall survival was longer for HCT recipients, the difference was not statistically significant (37% vs 25% at 3 years; P = .08). Our findings suggest that reduced-intensity conditioning allogeneic HCT in patients age 60-70 with acute myelogenous leukemia in CR1 reduces relapse and improves leukemia-free survival. Strategies that reduce nonrelapse mortality may yield significant improvements in overall survival. [ABSTRACT FROM AUTHOR]

Cytomegalovirus (CMV) disease constitutes a serious complication after allogeneic stem cell transplantation. For the clearance of CMV, CD8+ T cells are pivotal. Here, the novel streptamer technology was used at good manufacturing practice (GMP) level for adoptive transfer of CMV-specific T cells into acute leukemia patients with recurrent high CMV antigenemia after allogeneic stem cell transplantation. After a single transfusion, the frequency of CMV-specific CD8+CD45RA+CCR7- effector T cells increased dramatically from 0.0% to a maximum of 27.1% of all T cells. These T cells were clearly donor derived and did not stem from intrinsic reconstitution, as demonstrated by analysis of 1) donor chimerism through single-tandem repeats, 2) T-cell receptor excision circles, and 3) Vβ-chain typing by polymerase chain reaction. Clinically, the specific T-cell transfer resulted in a persistent clearance of the CMV antigenemia, which allowed the patients to discontinue toxic antiviral drug therapy without further high-level reactivation of CMV, demonstrating the power of the streptamer technology. Taken together, the streptamer technology offers the advantage of selecting virus-specific CD8+ T cells at GMP level for adoptive T-cell transfer, thus inducing long-lasting specific CD8+ T-cell responses without increasing the risk for graft-versus-host disease. [ABSTRACT FROM AUTHOR]

Treatment for multiple myeloma (MM) has changed beyond recognition over the past two decades. During the early 1980s, MM inevitably resulted in a slow progressive decline in quality of life until death after about 2 years, while today patients can expect a 50% chance of achieving a complete remission, median survival of 5 years, and a 20% chance of surviving longer than 10 years. An international expert opinion meeting (including members of the GIMEMA and DSMM study groups) was held in 2009. One of the outcomes of the meeting was the development of a consensus statement outlining contemporary optimal clinical practice for the treatment of MM. The international panel recommended that the state of the art therapy for MM should comprise: (a) evidence-based supportive care, (b) effective and well-tolerated chemotherapeutic regimens, (c) autologous hematopoietic stem cell transplant (ASCT) for patients suitable for intensive conditioning therapy, and (d) evidence-based incorporation of novel anti-MM agents. Maintenance strategies have also become increasingly important for the prolongation of remission after front-line therapies. In addition, improved understanding of the biology of MM has led to the development of novel biological therapeutic agents such as thalidomide, lenalidomide, bortezomib, and others. These agents specifically target intracellular mechanisms and interactions, such as those within the bone marrow microenvironment, and have been integrated into MM treatment. This report reviews recent clinical advances in the treatment strategies available for MM and provides an overview of the state of the art management of patients with MM. [ABSTRACT FROM AUTHOR]

Polyomavirus BK (BKV) is known as an important etiologic agent in the development of hemorrhagic cystitis (HC) after allogeneic stem cell transplant (SCT). To define T cell epitopes of the BKV proteins VP1 and sT, eight potential HLA-A2-binding peptides were synthesized based on computer algorithms. These peptides were co-incubated with CD8 + T cells from the peripheral blood (PB) of 25 healthy volunteers and seven patients suffering from HC after allogeneic SCT in a mixed-lymphocyte peptide culture (MLPC), which were subsequently screened by enzyme-linked immunospot (ELISPOT) assays and fluorescence-activated cell sorting (FACS) analysis. We found that CD8 + T cells from five of seven (71%) patients with HC presensitized with the BKV peptide VP1 p108 (LLMWEAVTV) specifically recognized T2 cells pulsed with VP1 p108. In contrast, only seven of 25 (28%) healthy volunteers had CD8 + T cells reactive with VP1 p108-pulsed T2 cells. The presence of VP1 p108-specific T cells could be confirmed by FACS analysis. The BKV peptide VP1 p108 seems to play an important role as an immunodominant peptide in the pathogenesis of HC in patients after allogeneic SCT, and might be a promising target for immunotherapies or even strategies to prevent the development of BKV-associated HC. [ABSTRACT FROM AUTHOR]

Background: Nilotinib is a tyrosine kinase inhibitor with high target specificity. Here, we characterized the effects of nilotinib for the first time on CD4+CD25+ regulatory T cells (Tregs) which regulate anti-tumor/leukemia immune responses. Design and Methods: Carboxyfluorescein diacetate succinimidyl ester (CFSE) and 5-bromo-2-deoxy -uridine (BrdU) were used to assess the proliferation and cell cycle distribution of Tregs. The expression of the transcription factor forkhead box P3 (FoxP3) and the glucocorticoid-induced tumor necrosis factor receptor (GITR) were measured by flow cytometry. Western blotting analysis was used to detect the effects of nilotinib on the signal transduction cascade of T-cell receptor (TCR) in Tregs. Results: Nilotinib inhibited the proliferation and suppressive capacity of Tregs in a dose-dependent manner. However, the production of cytokines secreted by Tregs and CD4+CD25- T cells was only inhibited at high concentrations of nilotinib exceeding the mean therapeutic serum concentrations of the drug in patients. Only high doses of nilotinib arrested both Tregs and CD4+CD25- T cells in the G0/G1 phase and down-regulated the expression of FoxP3 and GITR. In western blotting analysis, nilotinib did not show significant inhibitory effects on TCR signaling events in Tregs and CD4+CD25- T cells. Conclusions: These findings indicate that nilotinib does not hamper the function of Tregs at clinical relevant doses, while long-term administration of nilotinib still needs to be investigated. [ABSTRACT FROM AUTHOR]

CD4+CD25+ regulatory T cells (Tregs) can influence various immune responses. Little is known about the effects of the Abl/Src kinase inhibitor dasatinib on Tregs which regulate anti-tumor/leukaemia immune responses. The present study demonstrated that dasatinib inhibited proliferation of Tregs and CD4+CD25− T cells in a dose-dependent manner, which was associated with the decreased production of corresponding cytokines. Treatment of Tregs with dasatinib inhibited the suppressive capacity of Tregs. The mechanisms of this inhibition included arrest of cells in the G0/G1 phase of cell cycle, down-regulation of the transcription factor forkhead box P3, glucocorticoid-induced tumour necrosis factor receptor and the cytotoxic T lymphocyte associated protein 4 as well as inhibition of signaling events through Src and nuclear factor κB. Dasatinib showed an inhibitory effect on the proliferation and function of both Tregs and CD4+CD25− T cells at therapeutically relevant concentrations of the drug. Clinical administration of dasatinib might influence not only the graft-versus-leukaemia effect but also the graft-versus-host-disease in patients receiving dasatinib after allogeneic stem cell transplantation and/or donor lymphocytes infusion as the function of both Tregs and effector T cells are hampered in a similar way by dasatinib. [ABSTRACT FROM AUTHOR]

Objective: To investigate the inhibitory effects of dasatinib on proliferation, function, and signaling events on CD8+T cells. Materials and Methods: Carboxyfluorescein diacetate succinimidyl ester and 5-bromo-2-deoxyuridine were used to detect proliferation and cell cycle of CD8+T cells treated with dasatinib, respectively. Frequency and function of viral and leukemia-antigen–specific CD8+T cells from healthy donors were measured by tetramer staining and ELISPOT assay. Western blotting analysis was performed to detect T-cell receptor (TCR), nuclear factor kappa B (NF-κB) and Src signaling events in T cells treated with dasatinib or imatinib. Results: Dasatinib inhibited proliferation of CD8+T cells in a dose-dependent manner, which was associated with lower secretion of interferon-gamma and granzyme B, as well as with arrest of CD8+T cells in the G0/G1 phase of cell cycle. Inhibition of CD8+T cells was proven for blood samples from a patient under dasatinib medication when compared with their T-cell status without dasatinib. Western blotting confirmed that these effects were mediated through downregulation of the phosphorylation level of molecules from the TCR and the NF-κB signaling transduction cascade. Dasatinib proved to be more potent than imatinib on Src and TCR signaling events in Jurkat T cells. Conclusion: Our study demonstrated that dasatinib impaired proliferation and function of CD8+T cells via TCR and NF-κB signaling events without inducing apoptosis. Therefore, dasatinib might alter the graft-vs-leukemia effect and the graft-vs-host disease after allogeneic stem cell transplantation sustained by CD8+T cells. Dasatinib might also be used as a novel immunosuppressant agent. [Copyright &y& Elsevier]

Background. Cytomegalovirus (CMV) disease represents a serious complication after allogeneic peripheral blood stem cell (PBSC) transplantation. If possible, stem cell donors for transplantation are selected on the basis of their CMV serostatus. However, the cytomegalovirus-specific immune status can be further characterized by measuring CMV phosphoprotein 65-specific CD8+ T cell frequencies using tetramers, pentamers, and streptamers. We therefore investigated the specificity and sensitivity of all 3 methods and compared the results to patient serostatus. Methods. Twenty-three samples from CMV-seropositive healthy volunteers and 15 samples from CMV-seropositive patients before and after allogeneic PBSC transplantation were stained with tetramers, pentamers, or streptamers and analyzed by flow cytometry. Results. Similar frequencies of CD8+ and multimer+ T cells could be measured by all 3 multimer technologies. The lowest background signals (≤0.02%) were obtained using tetramer technology. Frequencies of 0.19%-2.48% of CMV phosphoprotein 65 495-503-specific CD8+ T cells were detected in healthy volunteers. Antigen-specific T cells were detected in only 11 (48%) of 23 seropositive healthy volunteers. CMV antigenemia before day 100 after allogeneic PBSC transplantation occurred in 2 of 3 patients without any specific T cells. Conclusion. These findings demonstrate the power of multimer staining and a certain limitation of serologic testing to define appropriate donors for transplantation. Therefore, whenever possible, CMV-seropositive donors of transplants to seropositive recipients should be screened for their CD8+ T cell frequency. All 3 multimer technologies can be used, yielding similar results. The streptamer technology additionally offers the advantage of selecting CMV phosphoprotein 65-specific CD8+ T cells at the good manufacturing practice level for adoptive T cell transfer. [ABSTRACT FROM AUTHOR]

The Bcr-Abl tyrosine kinase inhibitor imatinib mesylate is highly effective in the front-line treatment of chronic myeloid leukemia (CML) and is increasingly used in patients with residual disease or relapse after allogeneic stem cell transplantation (allo-SCT). Since an impairment of anti-viral CD8+ T-lymphocyte function by imatinib has been described, we question whether imatinib also affects specific anti-leukemic CD8+ T lymphocytes generated from the peripheral blood of healthy donors, and of CML patients after allo-SCT. Here, we assessed CD8+ T-cell expansion and function from healthy donors and patients with CML. The release of IFN-γ and granzyme B by CD8+ T-lymphocytes specific for R3, a recently described T-cell epitope peptide derived from a leukemia-associated antigen designated RHAMM/CD168 (receptor for hyaluronic acid mediated motility), was inhibited by imatinib in a dose-dependent fashion (range: 1–25 μM). These T cells were able to lyse cognate peptide labeled T2 cells and CD34+ CML progenitor cells. This lysis was inhibited by imatinib. The inhibitory effect was not associated with an increased rate of apoptosis of T cells and reversible after removal of imatinib. In the light of these findings, clinical administration of imatinib might result in the reduction of efficacy of the graft-versus-leukemia effect or other T-cell-based immunotherapies. [ABSTRACT FROM AUTHOR]

A pilot trial was initiated for chronic myeloid leukaemia patients, which employed imatinib for remission induction, followed by reduced-intensity conditioning and an in vivo T-cell depleted graft. Out of nine patients, six experienced a molecular relapse and one patient had a haematological relapse at a median interval of 5 months after transplantation. Five relapsing patients achieved a 2nd molecular remission after treatment with either donor lymphocyte infusions (n = 4) or imatinib (n = 1). Two of nine patients died due to infectious complications. The probability of survival 2 years after transplant was 74% (95% CI 42-100%). [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia bearing a RUNX1 gene mutation (RUNX1 + AML) has been proposed as a provisional entity in the 2016 WHO classification. Clinically, it has been associated with inferior response rates and outcome after conventional chemotherapy. Accordingly, RUNX1 + AML is allocated in the unfavorable prognostic category of the 2017 European Leukemia Net classification. Following allogeneic stem cell transplantation (alloSCT), RUNX1 was an unfavorable factor in one study in MDS/secondary AML, while data in de novo AML are scarce. Here, we present a retrospective study by the EBMT Acute Leukemia Working Party, aiming to elucidate the prognostic value of RUNX1 mutation in patients undergoing alloSCT for AML in first complete remission (CR1). Adults undergoing alloSCT for AML in CR1 from matched related or unrelated donors between 2013 and 2018 with complete information on conventional cytogenetics and RUNX1 mutational status were selected from the EBMT registry. Variables of interest were overall and leukemia-free survival (OS/LFS), GvHD/relapse free survival (GRFS), cumulative relapse incidence (RI), non-relapse mortality (NRM) and GvHD. Log rank test, Gray test and Cox regression models were used. 128 RUNX+ and 388 RUNX- patients were identified, >80% of both subgroups presenting as de novo AML. As expected, RUNX1+ patients rarely had co-mutations in NPM1 (6% vs. 26%, p=10−3), and showed a positive correlation with ASXL1 mutations (50% vs. 16%, p=10−4). Cytogenetic categories and other mutations (FLT3 -ITD, CEBPA) were equally distributed between the two groups, as were age, donor and graft type, CMV, conditioning and T cell depletion (TCD). Median follow-up was 16.4 (RUNX+) and 19.8 (RUNX-) months. 2y OS/LFS of the entire cohort were 64% [59-69]/57% [52-62], with no difference between RUNX1 + and RUNX1 - patients either in univariate or multivariate analysis (2y OS: 67.9% [57.3-78.5] vs. 63.1%v[57.4-68.7]p=0.15; 2y LFS: 57.6% [46.4-68.7] vs. 57% [51.4-62.6], p=0.38], figure 1). RUNX1 mutation neither had any impact among patients with normal karyotype (figure 2). Similarly, no other outcome parameter was influenced by RUNX1 mutational status. Instead, multivariate analysis revealed age and donor type as risk factors for OS, LFS and NRM. Poor cytogenetic was associated with higher RI and inferior LFS/GRFS, in vivo TCD with a lower rate of aGvHD II-IV, cGvHD, and better GRFS. Among patients with available information, FLT3 -ITD was an independent risk factor for relapse, LFS and GRFS. RUNX1 did not modify the role of FLT3 -ITD. Within the limits of a retrospective registry analysis, we could not find a negative influence of RUNX1 mutation on outcome after allogeneic SCT in CR1. Hence, transplantation in CR1 might overcome the unfavorable prognostic value of RUNX1 mutation and can be recommended as consolidation treatment in this entity. [ABSTRACT FROM AUTHOR]

In a phase I–II study for patients aged 55–65 years, we employed radioimmunotherapy using an anti-CD-66 antibody as part of a dose-reduced conditioning regimen, which was followed by a T-cell-depleted graft. 20 patients with a median age of 63 years suffering from acute leukaemia ( n = 17) or myelodysplastic syndrome ( n = 3) received the antibody labelled either with 188Rhenium ( n = 8) or with 90Yttrium ( n = 12) during conditioning. Radioimmunotherapy provided a mean dose of 21·9 (±8·4) Gy to the bone marrow with a significantly higher dose when 90Yttrium was used. Additional conditioning was fludarabine-based plus anti-thymocyte globulin in matched related donor transplants ( n = 11), or plus melphalan in matched unrelated donor transplants ( n = 9). Regimen-related toxicity was low, with two patients developing three episodes of grade III organ toxicity. All patients engrafted, grade II–IV acute graft- versus-host disease (GvHD) was observed in one patient (5%) and chronic GvHD in three patients (15%). The cumulative incidence of non-relapse mortality was 25%, the cumulative incidence of relapse 55%. The probability of survival was estimated to be 70% at 1 year and 52% at 2 years post-transplant, although no plateau was reached afterwards. In conclusion, radioimmunotherapy using the anti-CD66 antibody was feasible and safe in our elderly patient group and provided a high marrow dose. [ABSTRACT FROM AUTHOR]

The present study investigated the effects of CD34+ cell selection in 102 patients using the CliniMACS device. Patients were at high risk for the development of graft versus host disease (GvHD) because of age, or the use of a haploidentical, mismatched or unrelated donor (UD). The median age of the patients was 44 years. The CliniMACS procedure yielded 8·0 × 106 CD34+ cells/kg and the number of residual T cells was 1·3 × 104/kg (median). The median follow up was 20·6 months. The probability of graft failure was 7%. The rate of acute GvHD was low (compatible family donors 10%, UDs 17%, and haploidentical donors 26%) with no patient enduring more than grade II disease. The cumulative incidence of chronic GvHD at the median follow up after transplant was 15% for the compatible family donor group, 40% for the UD group and 78% in the group transplanted from a haploidentical donor Treatment failure was mainly because of transplant-related mortality, especially aspergillus infection, and not due to relapse. The probability of disease-free survival, stratified for the risk of treatment failure, was 27% for the high risk, 46% for the intermediate risk and 83% for the low risk group. [ABSTRACT FROM AUTHOR]

Abstract. Radioimmunotherapy (RIT) with radiolabelled monoclonal antibodies (mAbs) is an effective method of achieving myeloablation in leukaemia patients prior to stem cell transplantation (SCT). We wished to compare the approaches of specific binding to leukaemic blasts and non-specific binding to benign red marrow cells, which results in a myeloablative "cross-fire" effect. Therefore, we prospectively evaluated the biodistribution and biokinetics of the anti-CD45 mAb YTH 24.5 and the anti-CD66 mAb BW 250/183 with regard to their suitability for myeloablative RIT. The red marrow selective anti-CD66 mAb BW 250/183 (IgG1) binds to normal granulopoietic cells. In contrast, the anti-CD45 mAb YTH 24.5 (IgG2b) binds to 85-90% of acute leukaemic blasts and almost all haematopoietic white cells. Patients with leukaemic blast infiltration of the marrow <25% and assigned for RIT and SCT were included. Twelve patients (eight male, four female; median age 46±7 years) with AML (5), CML (5) or ALL (2) were examined. Both mAbs were labelled with technetium-99m. Within 48 h, 906±209 MBq [SUP99m]Tc-anti-CD66 mAb and 760±331 MBq [SUP99m]Tc-anti-CD45 mAb were injected consecutively. Scin-tigraphic and urinary measurements were performed 1, 2, 4 and 24 h after injection. Serum activities were evaluated 2, 5, 10, 15, 30 and 60 min and 2, 4 and 24 h after injection. Compared with the anti-CD45 mAb, the anti-CD66 mAb showed an approximately fourfold higher accumulation in the red marrow, a 2.5-fold lower accumulation in the liver and similar accumulation in the kidneys. The serum activity (% of the injected dose) initially decreased faster for the anti-CD45 mAb but was similar for the two mAbs 24 h after injection: 3.3%±1.2% (anti-CD66 mAb) and 2.4%±1.1% (anti-CD45 mAb). The cumulated urinary excretion was 17%±6.6% (anti-CD66 mAb) and 27.3%±7.9% (anti-CD45 mAb) 24 h after application. In these patients with low tumour load, the... [ABSTRACT FROM AUTHOR]

Discusses the case of six patients suffering from severe chronic graft versus host disease (GVHD) of the skin who did not respond to immunosuppresive therapy or relapsed after reduction of glucocorticosteriods. Treatment with psoralen plus ultraviolet-bath photochemotherapy; Clinical presentation of the condition; Alternative treatments.

Invasive fungal infections are a major cause of mortality in neutropenic cancer patients. To determine whether a polymerase chain reaction (PCR)-based assay enabled the identification of patients at risk for invasive fungal infections, a prospective monitoring once per week was performed during 92 neutropenic episodes in patients receiving chemotherapy for acute leukaemia or high-dose therapy followed by allogeneic or autologous stem cell transplantation, with the investigators blinded to clinical and microbiological data. PCR positivity was documented in 34 out of 92 risk episodes. All patients developing proven invasive fungal infection were found PCR positive, and PCR was found to be the earliest indicator of invasive fungal infection preceding clinical evidence by a mean of 5·75 d (range 0–14 d). In febrile neutropenic patients without a prior history of invasive fungal infection, a sensitivity of 100% and a specificity of 73% of the PCR assay for the development of proven or probable invasive fungal infection was documented. In conclusion, panfungal PCR performed prospectively once a week enabled the identification of patients at high risk for invasive fungal infections. [ABSTRACT FROM AUTHOR]

Assesses the potential of prospective polymerase chain reaction (PCR) screening for the early diagnosis of Aspergillus infection invasive aspergillosis (IA) after allogenic stem cell transplantation. Clinical signs of IA; Detection of Aspergillus-specific DNA sequences; Effectiveness of PCR screening method.

Background: There is increasing pressure for the recognition and replication of good clinical practice. We undertook a study to assess the variability in outcome of allogeneic bone-marrow transplantation among major European centres.Methods: We studied 13 centres, including 522 patients (aged 16-55 years), which had undertaken more than 30 bone-marrow transplantations between Jan 1, 1987, and Dec 31, 1995, for acute myeloid leukaemia in first complete remission. We undertook a (global) multivariate analysis of all factors known previously to influence outcome and a stratified analysis that initially defined, by multivariate analysis, significant variables in this study and then used a proportional-hazard model including centres.Findings: The overall results at 3 years were 57% (95% CI 53-61) for leukaemia-free survival (LFS), 23% (19-27) for relapse incidence (RI), and 26% (22-30) for treatment-related mortality (TRM) with a range for centres of 36-75%, 10-37%, and 8-54%, respectively. Both methods of analysis showed the centre effect to be highly significant for LFS and TRM, but not for RI. Variables associated with a significantly poor outcome were age over 43 years (p=0.01), time from diagnosis to first complete remission longer than 65 days (p=0.02), and centre (p=0.013) for LFS, and age over 43 years (p=0.023), time from first complete remission to transplantation of longer than 93 days (p=0.03), and centre (p=0.001) for TRM. Moreover, different centres had different prognostic criteria for good-risk or bad-risk patients indicating that risk factors do not have the same impact in each individual centre.Interpretation: The outcome of bone-marrow transplantation for acute myeloid leukaemia in first complete remission is influenced by the centre in which the procedure is done, even with adjustment for known prognostic risk factors. Significant prognostic factors vary among centres, which means that the relative risk is not the same in each individual centre. However, centres may treat populations with different risks of as yet unidentified prognostic factors. Experience may partly account for the difference in outcome among centres. [ABSTRACT FROM AUTHOR]

Simple Summary: Allogenic stem cell transplantation is a treatment option for various hematological diseases. Due to the intensity of the therapy regimes used, there is a substantial therapy associated mortality and morbidity. Therefore, it is crucial to identify patients with increased risk for treatment associated complications. Sarcopenia, defined as the loss of muscle mass and strength is a risk factor in various diseases. Aim of our study was to implement and evaluate the predictive power of a sarcopenia assessment, based on muscle mass, muscle strength and aerobic capacity (by measuring peak oxygen uptake), on all-cause and non-relapse mortality. A total of 178 patients were screened, with 28% suffering from sarcopenia before transplantation. Our results show a three-fold increase in all-cause and non-relapse mortality in this subpopulation compared to non-sarcopenic patients within a 12-month follow up. The importance of physical performance status demonstrated, raises the question, if exercise interventions might even allow to decrease mortality and morbidity. Allogenic stem cell transplantation (aSCT) is the only potentially curative treatment for high-risk hematological diseases. Despite advancements in supportive measures, aSCT outcome is still affected by considerable transplant-related mortality. We implemented a new sarcopenia assessment prior to aSCT to evaluate its predictive capability for all-cause and non-relapse mortality. Therefore all patients initially scheduled for aSCT within a 25-month period were screened during pre-transplantation-routine for muscle mass, grip strength, and aerobic capacity (AC) by measuring peak oxygen uptake (VO2peak). Patients were assigned to one of five groups adapted according current sarcopenia guidelines. Primary endpoints were all-cause and non-relapse mortality within a follow up time of up to 12 months. A total of 178 patients were included and rated as normal (n = 48), impaired aerobic capacity (n = 56), pre-sarcopenic (n = 26), sarcopenic (n = 27), and severe sarcopenic (n = 22) without significant age-differences between groups. Patients presenting with sarcopenia showed a significant three-fold increase in all-cause and non-relapse mortality compared to patients with normal screening results. AC showed to be the strongest single predictor with a more than two-fold increase of mortality for low AC. We conclude that risk stratification based on combination of muscle mass, grip strength, and AC allowed identifying a subgroup with increased risk for complications in patients undergoing aSCT. [ABSTRACT FROM AUTHOR]

Anti-NCA antigen antibody BW 250/183 (Anti-Granulocyte) localizes more than 50% of injected antibody dose to the bone marrow. Therefore, this antibody is promising for adjuvant conditioning radioimmunotherapy of bone marrow before bone marrow transplantation. To examine its potential use for radioimmunotherapy, we developed an efficient and reproducible technical protocol for labelling anti-NCA antigen antibody BW 250/183 with generator-produced rhenium-188, aiming at both high radiochemical yield and high specific activity. 188Re-labelled BW 250/183 antibody was used in 12 patients with advanced leukaemia. Labelling of BW 250/183 with 188Re was accomplished by the direct radiolabelling method using tris-(2-carboxyethyl) phosphine (TCEP) as the reducing agent. Twelve patients with recurrent acute or chronic leukaemia were treated with activities of 6.5–12.4 GBq of 188Re-labelled BW 250/183. Standard gamma camera scintigraphy was used to evaluate the biodistribution, and a region of interest analysis together with the MIRDOSE 3.1 software was applied to determine the radiation doses to relevant tissues. The 188Re-BW 250/183 antibody was labelled in high radiochemical yield, with high radiochemical purity (94%±3%) and specific activity (5.55–7.4 GBq/mg) within 1 h. The preliminary biodistribution studies showed persistent uptake of 188Re-BW 250/183 in bone marrow. The radiation absorbed doses (mGy/MBq) delivered to the total body, red marrow, liver, spleen and kidneys were 0.13±0.02, 1.45±0.71, 0.43±0.21, 1.32±0.99 and 0.71±0.17, respectively. TCEP reduction enabled the direct, fast and effective labelling of the monoclonal antibody BW 250/183 with 188Re. Preliminary clinical results suggest delivery of a significant radiation dose to bone marrow and thus the potential for adjuvant conditioning therapy before BMT. [ABSTRACT FROM AUTHOR]