Unrelated Donor Stem Cell Transplantation Research Articles

Unmanipulated haploidentical in comparison with matched unrelated donor stem cell transplantation in patients 60\xa0years and older with acute myeloid leukemia: a comparative study on behalf of the ALWP of the EBMT

BackgroundAcute myeloid leukemia (AML) is both more common and with more biologically aggressive phenotype in the elderly. Allogenic stem cell transplantation (allo-SCT) is the best treatment option in fit patients. Either HLA-matched unrelated donor (MUD) or haploidentical (Haplo) donor are possible alternative for patients in need.MethodsWe retrospectively compared non-T-cell-depleted Haplo (n = 250) to 10/10 MUD (n = 2589) in AML patients ≥ 60 years.ResultsMedian follow-up was 23 months. Disease status at transplant differs significantly between the two groups (p < 10−4). Reduced intensity conditioning (RIC) was administrated to 73 and 77% of Haplo and MUD, respectively (p = 0.23). Stem cell source was the bone marrow (BM) in 52% of the Haplo and 6% of MUD (p < 10−4). Anti-thymocyte globulin (ATG) was most frequently used in MUD (p < 10−4) while post-Tx cyclophosphamide (PT-Cy) was given in 62% of Haplo. Engraftment was achieved in 90% of the Haplo vs 97% of MUD (p < 10−4). In multivariate analysis, no significant difference was found between Haplo and MUD for acute (a)graft versus host disease (GVHD) grade II–IV, relapse incidence (RI), non-relapse mortality (NRM), leukemia free survival (LFS), graft-versus-host-free-relapse free survival (GRFS), and overall survival (OS). Extensive chronic (c)GVHD was significantly higher for MUD as compared to Haplo (HR 2, p = 0.01, 95% CI 1.17–3.47). A propensity score analysis confirmed the higher risk of extensive cGVHD for MUD without differences for other outcomes.ConclusionsAllo-SCT from both Haplo and MUD are valid option for AML patients ≥ 60 years of age with similar results. Transplantation from MUD was associated with higher extensive cGVHD. Our findings suggest that Haplo is a suitable and attractive graft source for patients≥ 60 with AML in need of allo-SCT.

Evolutionary basis of HLA-DPB1 alleles affects acute GVHD in unrelated donor stem cell transplantation

AbstractHLA-DPB1 T-cell epitope (TCE) mismatching algorithm and rs9277534 SNP at the 3′ untranslated region (3′UTR) in the HLA-DPB1 gene are key factors for transplant-related events in unrelated hematopoietic cell transplantation (UR-HCT). However, the association of these 2 mechanisms has not been elucidated. We analyzed 19 frequent HLA-DPB1 alleles derived from Japanese healthy subjects by next-generation sequencing of the entire HLA-DPB1 gene region and multi-SNP data of the HLA region in 1589 UR-HCT pairs. The risk of acute graft-versus-host disease (aGVHD) was analyzed in 1286 patients with single HLA-DPB1 mismatch UR-HCT. The phylogenetic tree constructed using the entire gene region demonstrated that HLA-DPB1 alleles were divided into 2 groups, HLA-DP2 and HLA-DP5. Although a phylogenetic relationship in the genomic region from exon 3 to 3′UTR (Ex3-3′UTR) obviously supported the division of HLA-DP2 and HLA-DP5 groups, which in exon 2 showed intermingling of HLA-DPB1 alleles in a non–HLA-DP2 and non–HLA-DP5-group manner. Multi-SNP data also showed 2 discriminative HLA-DPB1 groups according to Ex3-3′UTR. Risk of grade 2-4 aGVHD was significantly higher in patient HLA-DP5 group mismatch than patient HLA-DP2 group mismatch (hazard ratio, 1.28; P = .005), regardless of donor mismatch HLA-DP group. Regarding TCE mismatch, increasing risk of aGVHD in patient HLA-DP5 group mismatch and TCE-nonpermissive mismatch were observed only in patients with TCE-permissive mismatch and patient HLA-DP2 group mismatch, respectively. Evolutionary analysis revealed that rs9277534 represented a highly conserved HLA-DPB1 Ex3-3′UTR region and may provoke aGVHD differently to TCE mismatching algorithm, reflecting exon 2 polymorphisms. These findings enrich our understanding of the mechanism of aGVHD in HLA-DPB1 mismatch UR-HCT.

Timelines, an important tool for matched unrelated donor stem cell transplant: A case report and review of literature

Stem cell transplant (SCT) is the “standard of care” for several malignant disorders such as leukemia as well as nonmalignant disorders such as thalassemia and aplastic anemia. In SCT, family (usually a sibling) is screened for human leukocyte antigen (HLA)-matched related donor (MRD), and failing this, matched unrelated donor (MUD) transplants are considered. There are seven major steps involved in the process of MUD SCT, while the patient is prepared for receiving the SCT in parallel after achieving remission. Here, we report the timelines involved in MUD SCT along with a case report and review of literature.

Beneficial Role of Low-Dose Antithymocyte Globulin in Unrelated Stem Cell Transplantation for Adult Patients with Acquired Severe Aplastic Anemia: Reduction of Graft-versus-Host Disease and Improvement of Graft-versus-Host Disease–Free, Failure-Free Survival Rate

Stem cell transplantation (SCT) from an unrelated donor (URD) is often considered in patients with severe aplastic anemia (SAA) whom immunosuppressive therapy failed and matched sibling donor is not available. To reduce the incidence of graft-versus-host disease (GVHD) in URD SCT, introducting antithymocyte globulin (ATG) into the conditioning regimen has been proposed. Although ATG was shown to play a role in reducing GVHD in a cohort with diverse hematologic diseases, its role in SAA remains uncertain. The aim of this study was to determine the efficacy and toxicity of ATG in URD SCT for adult patients with SAA. We investigated 83 adult patients with SAA who underwent URD SCT between 2003 and 2014. The transplantation strategy consisted of total body irradiation (total 800 cGy) and cyclophosphamide (total 100 mg/kg to 120 mg/kg), followed by tacrolimus and a short-term methotrexate. We divided patients into 2 groups: group 1 (n = 25), which received HLA-matched (8/8) bone marrow (BM) without ATG, and group 2 (n = 58), which received SCT from either an HLA-mismatched donor or peripheral blood (PB). Thereafter, group 2 was subdivided according to ATG use into group 2A (without ATG, n = 26), which served as a historical cohort, and group 2B (with ATG, n = 32). Rabbit ATG (Thymoglobulin; Genzyme-Sanofi, Lyon, France) was used in group 2B at a dose of 2.5 mg/kg. The median age of all patients was 30 years (range, 17 to 59 years). The incidence of GVHD was significantly lower in group 2B than group 2A, as demonstrated by the rate of grade II to IV acute GVHD at day 100 (31.2% versus 61.5%, P = .003) and the rate of chronic GVHD at 3 years (21.9% versus 65.4%, P = .002). The overall survival rates of the 3 groups were similar. However, GVHD-free, failure-free survival (GFFS) was significantly higher in group 2B than group 2A (P = .034). A multivariable model identified use of ATG as an independent factor affecting grades II to IV acute GVHD (hazard ratio [HR], 2.902; 95% confidence interval [CI], 1.417 to 5.942; P = .004), chronic GVHD (HR , 3.005; 95% CI, 1.279 to 7.059; P = .012), and GFFS (HR, 2.363; 95% CI, 1.162 to 4.805; P = .014). Toxicities, including infectious complications, were not different among the 3 groups. In conclusion, low-dose ATG (2.5 mg/kg) can reduce the incidence of acute and chronic GVHD and improve the quality of life in patients with SAA who receive stem cells from either an HLA-mismatched donor or PB; importantly, these benefits are achieved without increased toxicity. Furthermore, ATG can be considered in URD SCT from HLA-matched BM cells.

Reduction of Relapse after Unrelated Donor Stem Cell Transplantation by KIR-Based Graft Selection.

Besides donor T cells, natural killer (NK) cells are considered to have a major role in preventing relapse after allogeneic hematopoietic stem cell transplantation (HSCT). After T-cell-depleted haploidentical HSCT, a strong NK alloreactivity has been described. These effects have been attributed to killer-cell immunoglobulin-like receptors (KIR). Abundant reports suggest a major role of KIR not only on outcome after haploidentical HSCT but also in the unrelated donor setting. In this review, we give a brief overview of the mechanism of NK cell activation, nomenclature of KIR haplotypes, human leukocyte antigen (HLA) groups, and distinct models for prediction of NK cell alloreactivity. It can be concluded that KIR-ligand mismatch seems to provoke adverse effects in unrelated donor HSCT with reduced overall survival and increased risk for high-grade acute graft-versus-host disease. The presence of activating KIR, as seen in KIR haplotype B, as well as the patient’s HLA C1/x haplotype might reduce relapse in myeloid malignancies.

The combination of cyclosporine and mycophenolate mofetil is less effective than cyclosporine and methotrexate in the prevention of acute graft-versus host disease after stem-cell transplantation from unrelated donors.

Acute graft-versus-host disease (GVHD) is the major treatment-related complication after stem-cell transplantation (SCT) from unrelated-donors. Several GVHD prophylaxis regimens have been explored, but no regimen has shown superiority. We analyzed transplantation outcomes in 472 consecutive unrelated-donor SCT recipients, using cyclosporine/methotrexate (MTX, n=314) or cyclosporine/mycophenolate-mofetil (MMF, n=158) for GVHD prophylaxis. Neutrophil engraftment was faster after MMF, days 11 and 14, respectively (P=.001). Acute GVHD grade II-IV and III-IV occurred in 47% and 28% after MMF compared to 27% and 12% after MTX, respectively (P<.001). Nonrelapse mortality (NRM) was 44% and 24%, respectively (P<.001). Death associated with GVHD occurred in 25% and 8% (P<.0001), while other NRM causes occurred in 19% and 16%, respectively (P=.39). Relapse mortality was similar. Overall survival was better after MTX, 40% and 29%, respectively (P=.006). However, this difference had only borderline significance when adjusting for differences in patient characteristics (HR, 1.3, P=.08). To minimize potential selection bias we analyzed outcomes on the basis of an intention-to-treat like analysis. During the years 2008-2009, the leading GVHD prophylaxis regimen for unrelated-donor SCT included MMF (89% of transplants). During the other periods, MTX was used predominantly (82% of transplants). The two periods were otherwise well-matched. Acute GVHD occurred more often in 2008-2009. Death associated with GVHD occurred more often, while other NRM causes occurred less often resulting in similar NRM and overall survival. In conclusion, cyclosporine/MMF is associated with faster engraftment and possibly with less organ toxicity than cyclosporine/MTX. However, it is associated with increased rates of acute GVHD and GVHD-associated deaths.

Matched unrelated donor hematopoietic stem cell transplantation - our results

Introduction. Allogeneic stem-cell transplantation is only potentially curative therapy for variety of hematology malignancies, such as acute and chronic leukemia, myelodisplastic syndrome and aplastic anemia, but also promising treatment option for other disorders. If we know that only 25% of patients have an human leukocyte antigen identical sibling donor, it is obvious that matched unrelated donor hematopoietic stem cell transplantation is an alternative for the rest of the patients. Material and Methods. Since 2013, matched unrelated donor hematopoietic stem cell transplantation has been performed routinely in the Military Medical Academy. Results. We hereby present the outcome after 77 procedures in 75 patients. Considering primary diseases, 35 patients had acute myeloid leukemia, 25 patients had acute lymphoid leukemia, 5 patients had chronic myeloid leukemia, 9 patients had myelodisplastic syndrome and we performed the transplant on 1 patient with chronic lymphocyte leukemia, 1 patient with aplastic anemia and 1 patient with T lymphoblastic lymphoma. Conclusion. It is difficult to make clear conclusions based on this heterogeneous group of patients, but it seems that these results are encouraging. Future research will be performed to evaluate matched unrelated donor and identical sibling hematopoietic stem cell transplantation in the homogenous groups with respect to primary diseases.

Heterozygous RTEL1 Variants Are Associated with Bone Marrow Failure and Abnormal Clinical Phenotype

IntroductionHeterozygous RTEL1 mutations have recently been described in familial pulmonary fibrosis (PF) but are not known to be associated with cytopenias or bone marrow failure (BMF), in contrast to heterozygous mutations in other telomere maintenance genes TERT, TERC and TINF2. Constitutional BMF syndromes typically present with less severe pancytopenia and it is often unclear if they have hypocellular MDS (hypoMDS) or non-severe AA (NSAA) morphologically.MethodsWe screened 284 patients with idiopathic AA or uncharacterised BMF and 172 patients with MDS or acute myeloid leukemia (AML) for TL and RTEL1 variants, and for the other currently known telomere gene complex (TGC) mutations, after excluding patients with Fanconi anemia, DBA or other known inherited BMF syndrome. TL was measured using a monochrome multiplex quantitative PCR method on peripheral blood mononuclear cells. Illumina Nextera-amplicon sequencing was used to screen exons of the DC genes (DKC1, TERC, TERT, RTEL1, CTC1, NHP10, NOP2, USB1, WRAP53, TINF2, PARN and ACD) by MiSeq platform. Constitutional DNA was also analysed in 10 patients (skin 9, buccal swab 1) with RTEL1 variants. A targeted gene panel of 24 genes of an Illumina Tru-Seq Custom Amplicon workflow and platform was used to identify genes frequently mutated in MDS/AML. Impact of mutations was predicted based on 3D structure information from comparative modelling for the helicase domain, comprising the HD1 and HD2 subdomains, a Fe-S cluster and an ARCH domain, and for two harmonin-like (HML) domains and a RING finger domain, located in the C-terminal regulatory region of RTEL1.ResultsHeterozygous RTEL1 variants were identified in 20 (4.4%) patients. RTEL1 variant allele frequency (VAF) was 45-70% consistent with heterozygous inheritance in all cases. TL was short in 18 (90%) patients, being < 1st centile in 15 and <10th centile in 3. 2 patients had normal TL, <20th centile and >50th centile, respectively. Median age was 35 years (range 18-73). 15/20 (75%) had a hypocellular BM (7 hypoMDS, 5 non-severe AA, 3 ICUS), and 1 each with RAEB1, RAEB2, CMML1, AML and isolated macrocytosis. 3 patients had abnormal karyotype: +8 (hypoMDS), -Y,+1,del(1) (hypoMDS), del7q (RAEB1). 2 other patients with hypoMDS had somatic mutations: U2AF1 (30% VAF) with ASXL1 (27% VAF); U2AF1 (43% VAF). Lung abnormalities were early PF (1), interstitial lung disease (1), and abnormal lung function with reduced TLCO (1) and an obstructive picture (1). Liver fibrosis with portal hypertension and varices and reticulate skin pigmentation were present in the patient with ILD, 2 patients had dystrophic nails, and 1 unexplained mild hepato-splenomegaly. 2 patients had familial MDS, 5 had a family history of cancers affecting first-degree relatives, and 2 had skeletal and cartilage anomalies, associated with learning difficulties in 1 patient. 8/15 patients with hypocellular BM required no treatment (5 hypoMDS and 3 NSAA), one hypoMDS had CR with ciclosporin and another underwent successful unrelated donor stem cell transplant; for NSAA, 2 received ATG with CSA, with PR followed by relapse in one, the other was lost to follow up, and 1 was androgen responsive. 16/20 (80%) patients are alive; 3 patients with RAEB or AML died of progressive disease and 1 patient with ICUS and severe constitutional features died from lymphoma 10 years after presentation.Mutations were spread throughout the entire RTEL1 sequence (summarised in Figure). 3D structure analysis predicted the missense RTEL1 mutations would result in disturbance of the FeS cluster and/or interfere with DNA binding, destabilisation of the HD1, HD2 or the ARCH sub-domains of the helicase domain, or destabilisation of inter-domain interactions. One HML1 mutation occurred in a loop opposite the putative ligand binding site and the rest in the variable regions outside the conserved domains. RTEL1 variants were associated with TERT mutations in 4 patients, of which 3 were known pathogenetic and 1 novel TERT mutation with low telomerase activity on TRAP assay confirming its pathogenetic nature.ConclusionsWe show for the first time that heterozygous RTEL1 mutations occur in 4.4% of patients, most commonly in young patients with a hypocellular BM, and often a family history of BMF/malignancy, and less often with high risk MDS/AML. Abnormal clinical features were present in a third of patients, some similar to but others distinct from dyskeratosis congenita. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Family Mismatched Donor Transplantation for Myelofibrosis: A Retrospective Analysis of the EBMT Chronic Leukaemia Working Party

Background: Allogeneic stem cell transplantation is a treatment option for patients with advanced myelofibrosis. Problems encountered include an increased risk of delayed or poor engraftment and in the mismatched unrelated donor setting a higher rate of GVHD and particularly poor outcomes. As for other indications for allogeneic stem cell transplants, patients for whom either a matched sibling or matched unrelated donor is not available are considered for either a double umbilical cord blood, a mismatched unrelated donor or haploidentical stem cell transplant. Data on the latter option are limited and we reviewed registry data on all family mismatched donor transplants performed between 2001 and 2015 and reported to the EBMT registry.Results: Records retrieved 69 patients with myelofibrosis transplanted between November 2001 and November 2015. 44 (64%) were male. 50 (74%) had primary myelofibrosis,18 (27%) had secondary myelofibrosis (6 from ET, 5 from PRV and 7 others) and unknown 1(2%). Of 25 patients for whom the JAK2 V617F mutation status was known, 15 (22%) harboured the mutation. Patient Karnofsky performance status was > 70% in 98%.Of the mismatched family donors, 47 (68%) were male and 22 (31%) female. Donors were HLA mismatched at 1 locus in 12 (17%) and 2 or more loci in 48 (69%). Donor-recipient serology combinations were CMV -/- in 8 (12%), +/- in 4 (6%), -/+ in 15 (22%) and +/+ in 34 (49%) missing 8 (12%).Bone marrow was the stem cell source in 34 (49%) and peripheral blood in 35 (51%). The median total nucleated cell count (TNC) infused was 7.5x108/kg (range 2.3-21x108/kg) from data available in 17 patients. The median CD34+ cell dose was 6.9x106/kg (range 1.9-18.18x106/kg) from data available in 19 patients.Conditioning was myeloablative in 48 (70%) and RIC in 21 (30%) The conditioning regimes were varied but the predominant ones were Fludarabine, Busulphan, ATG (FBATG) and Thiotepa, Busulphan, Fludarabine (TBF). TBI was administered in 8 (12%) and in vivo T cell depletion in 22 (32%), ex-vivo T cell depletion in 5 (7%) patients. GVHD prophylaxis varied with post transplant Cyclophosphamide administered in 34/67 (49%) and ATG in 19/67 patients (28%).Neutrophil engraftment was established in 53 (82%) at a median of 20 days (range 11-83). Primary graft failure occurred in 8 (12%) and secondary graft failure in 4 (6%). This occurred at a median of 12 months (range 4.5-35 months). Eleven of these patients had a second allograft at a mean interval of 6.4 months. Responses to the first allograft (censoring for patients who had a second allograft) with data available in 45 patients, showed that complete remission was achieved in 35 patients (78%), 6 (13%) were never in CR and 4 (9%) were not evaluable.The cumulative incidence of grade II-IV acute GvHD at 100 days was 12% (95% CI 4-21%) and for grade III-IV acute GvHD at 100 days it was 5% (95% CI 3-11%). Data for chronic GVHD was valid in 49 patients. The cumulative incidence of chronic GvHD at 2 years was 62% (95% CI 47-76%). The cumulative incidence of limited cGvHD was 45% (95% CI 31-59%) whereas the cumulative incidence of extensive cGvHD was 10% (95% CI 2-19%).The median follow up was 24 months (95% CI 13-35 months). The 2-year OS was 51% (95% CI 37-76%) and the 5-year OS was 38% (95% CI 21-55%). The 2-year RFS was 44% (95% CI 30-59%) and the 5-year RFS was 31% (95% CI 15-48%). The 2 year cumulative incidence of relapse was 14% (95% CI 5-24%). The 2 year NRM was 41% (95% CI 28-55%), which increased to 54% (95% CI 37-72%) at 5 years.The main causes of death were infection (16, 24%), GVHD (7, 10%) organ damage or failure (3, 5%), relapse/disease progression (1, 2%) and secondary malignancy or PTLD (1, 2%). On univariate analysis there was no significant effect of recipient gender, donor gender, degree of HLA mismatch 1 vs >1 Ag MM, CMV matching between donor and recipient, primary or secondary MF, disease stage at transplant (chronic versus advanced phase), conditioning intensity, conditioning regimen, GVHD prophylaxis with ATG or post transplant cyclophosphamide or stem cell source on overall survival.Conclusion: Concerns regarding engraftment and secondary graft failure have excluded patients with myelofibrosis from clinical trials of mismatched related donor transplant. The data suggest that engraftment is feasible, and PFS and OS can be attained with limited severe chronic GVHD with family mismatched donors in this setting. DisclosuresCiceri:MolMed SpA: Consultancy.

Coexistence of inversion 16 in chronic myeloid leukaemia in blast crisis

Chronic myeloid leukaemia (CML) is consistently associated with the BCR-ABL1 fusion gene located on the derivative chromosome 22 (Philadelphia chromosome, Ph + ve) as a result of a t(9;22)(q34;q11.2) translocation. We describe a 36-year-old male in blast phase CML presenting with acute myelomonocytic leukaemia and eosinophilia. Five months after initial disease diagnosis and despite being treated with standard imatinib therapy (400 mg daily) conventional cytogenetic analysis (CCA) demonstrated the evolution of a chromosome 16 pericentric inversion (inv(16)(p13q22)) within the already Ph + ve cells. Bone marrow aspiration and biopsy revealed 60% blasts, positive for CD34, HLADR, CD33 and CD13. Fluorescence in situ hybridization (FISH) and reverse transcription–polymerase chain reaction (RT-PCR) confirmed presence of a CBFβ-MHY11 rearrangement whilst next generation sequencing (NGS) detected an E255K point mutation within the BCR-ABL1 tyrosine kinase domain. Neither the CBFβ-MHY11 rearrangement nor the E225K point mutation were present at diagnosis. The patient received a combination of daunorubicin (60 mg/m2) and cytarabine (100 mg/m2) and had his tyrosine kinase inhibitor (TKI) changed to nilotinib before undergoing a male unrelated donor (MUD) stem cell transplant (SCT). The t(9;22) and inv(16) rearrangements persisted at day 100 post MUD SCT and his TKI was further switched to dasatinib. The patient presented with pleural effusions and had subsequent CNS relapse and passed away from relapsed disease and infective complications, 19-month post MUD allograft.

Successful Matched Unrelated Donor Stem Cell Transplant in Hb Bart's Disease

Successful Matched Unrelated Donor Stem Cell Transplant in Hb Bart's Disease

Outcomes after Matched Unrelated Donor Stem Cell Transplantation in Chronic Granulomatous Disease – an Update

Outcomes after Matched Unrelated Donor Stem Cell Transplantation in Chronic Granulomatous Disease – an Update

Impact of Different In Vivo T Cell Depletion Strategies on Outcomes Following Hematopoietic Stem Cell Transplantation for Idiopathic Aplastic Anaemia: A Study on Behalf of the EBMT SAA Working Party

To determine the optimal serotherapy regimen in idiopathic aplastic anaemia stem cell transplantation, we analysed 1837 patients who underwent either in vivo T cell depletion with either ATG (n=1283) or Alemtuzumab (n=261) or no serotherapy (n=293) as part of their conditioning regimen. All patients had either undergone a matched sibling or matched unrelated donor stem cell transplant (at least 6 out of 6). Data was obtained retrospectively from the EBMT SAA database, between the periods 2000-2013. The major endpoints were graft versus host disease, overall survival and event free survival. Events were classified as graft failure, secondary malignancy, relapse and requirement for second transplant. The median follow up was 34 months in the ATG group, 30.9 months in the Alemtuzumab group and 47.9 months in the no serotherapy group. Rate of grade 2-4 acute GVHD was 19.1% without serotherapy; this was higher than that observed with both ATG (13.3%, p<0.001) and Alemtuzumab (6.7%, p<0.001; ATG vs Alemtuzumab: p=0.012). Cumulative incidence of chronic GVHD at 36 months was 30.4% without serotherapy; this was higher than that observed with both ATG (20.8%, p=0.021) and Alemtuzumab (14.7%, p=0.003; ATG vs Alemtuzumab: p=0.083). In multivariate analysis, grade 2-4 acute and chronic GVHD rates were significantly lower with Alemtuzumab compared to no serotherapy (Odds Ratio ratio (OR) = 0.16, p< 0.001 95%CI 0.08-0.31 and HR= 0.38, 95% CI 0.24-0.62, p< 0.001 respectively). Similarly, acute and chronic GVHD were lower with Alemtuzumab compared to ATG (OR = 0.26;p<0.001 95%CI 0.14-0.47 and HR = 0.58; 95%CI 0.38-0.89, p=0.012 , respectively). Acute and chronic GVHD were higher without serotherapy compared to ATG (OR = 1.65; p =0.01 95%CI 1.12-2.41 and HR = 1.51; 95%CI 1.12-2.04, p=0.008 , respectively). There was no difference in event free survival between the three groups. However, overall survival at 36 months was 73.3%, 81.3% and 81.5 in no serotherapy, ATG and alemtuzumab, respectively (ATG vs no serotherapy p=0.01; Alemtuzumab vs no serotherapy p=0.025; Alentuzumab vs ATG p=0.604). In multivariate analysis overall survival favoured in vivo T cell depletion compared to no serotherapy; (Alemtuzumab vs no serotherapy, HR=0.44; 95%CI 0.29-0.67, p<0.001); (no serotherapy vs. ATG HR=1.55; 95%CI 1.19-2.01, p=0.001). Among serotherapy, Alemtuzumab was associated with better OS as compared with ATG (OR=0.68; 95%CI 0.48-0.98, p=0.037). Our results suggest that use of in vivo T cell depletion in sibling and unrelated matched stem cell transplantation in idiopathic aplastic anaemia leads to a survival advantage. Alemtuzumab is associated with less GVHD than ATG without affecting event free survival. [Display omitted] DisclosuresSnowden:Celgene: Other: Educational support, Speakers Bureau; Janssen: Other: Educational support, Speakers Bureau; MSD: Consultancy, Other: Educational support, Speakers Bureau; Sanofi: Consultancy. Dufour:Pfizer: Consultancy. Risitano:Pfizer: Consultancy; Novartis: Research Funding; Rapharma: Consultancy, Research Funding; Alnylam: Consultancy, Research Funding; Alexion Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Off Label Use: this paper includes discussion of the use of alentuzumab for GVHD prophylaxis, which is currently off-label.

Comparison of Matched/Mismatched Unrelated Donor Stem Cell Transplantation to Autologous Stem Cell Transplantation for Acute Myeloid Leukemia in First Complete Remission: A Study from the Acute Leukemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT)

Background. Optimal post-remission strategy for patients with acute myeloid leukemia (AML) is still matter of debate. Allogeneic Stem Cell Transplant (allo-HSCT) is the most effective treatment to prevent leukemia relapse, and for patients who lack a sibling donor transplantation from a matched or mismatched unrelated donor (URD) is usually the preferred alternative. However, increase in donor-recipient HLA mismatch, patient age and comorbidity scores lead to higher non relapse mortality (NRM) rates; moreover incidence of chronic GVHD is rather high after transplant from unrelated donors. Autologous Stem Cell Transplant (ASCT) has several advantages compared to allo-HSCT including low NRM, no GVHD risk, less late effects and better quality of life. The aim of the current study was to compare the outcome of allo-HSCT from matched (10/10 URD) or mismatched unrelated donor at a single HLA-locus (9/10 URD) to ASCT in patients with AML in first CR.Patients and methods. We performed a retrospective analysis of 2689 AML patients receiving 10/10 URD (n=1260), 9/10 URD-HSCT (n=356) or ASCT (n=1073) in first CR between 2005 and 2013 and reported to the ALWP of the EBMT.Results. Median FU was 35, 27 and 27 months for ASCT, 10/10 and 9/10 URD, respectively (p<10-4); median age was 48.7, 50.8, 48.7 years, respectively (p=10-3). Time from diagnosis to transplant was longer for URD compared to ASCT (p<10-4); patients who received URD had more frequently poor risk cytogenetics (p<10-4), were more likely to get a TBI-based conditioning (p<10-4) and were transplanted more recently (p<10-4), compared to patients who received ASCT. The 2-year cumulative incidence of relapse (RI) for ASCT, 10/10 and 9/10 URD were 46.3±3%, 24.9±3% and 27.7±5%, respectively (p<10-5), while the 2-year NRM rates were 3.1±2%, 16.4±4% and 20.5±4%, respectively (p<10-5). The 2-year KM estimates of leukemia-free survival (LFS) were 50.6±3% for ASCT, 58.7±3% for 10/10 URD and 51.8±6% for 9/10 URD (p=0.002), while the 2-year overall survival (OS) rates were 68.2±3, 63.6±3% and 55.1±6%, respectively (p<10-4). ASCT showed significantly higher RI compared to URD independently of cytogenetic risk (good risk: p<10-4, intermediate and poor risk: p<10-5); accordingly, 2y LFS was significantly better for URD compared to ASCT in all risk groups (good risk: p=0.034, intermediate risk: p=0.0007, poor risk: p=0.021). ASCT and URD showed similar OS in good and poor risk patients, while in intermediate risk group ASCT resulted in similar OS compared to 10/10 URD and better OS compared to 9/10 URD (66.2±4% for ASCT, 65.8±5% for 10/10 URD, 55.4±7% for 9/10 URD, p=0.012) (Fig 1). Within intermediate cytogenetic risk group, FLT3-ITD mutational status affected outcome; in patients harboring FLT3-ITD 10/10 URD showed the best LFS and OS (LFS: 36.3±11% for ASCT, 58.4±7% for 10/10 and 34±13% for 9/10 URD, p=10-3; OS: 51.7±12%, 62.2±7% and 41.4±14%, respectively, p=0.02). Conversely, in patients with wild type FLT3-ITD URD showed better LFS compared to ASCT (51.3±8% for ASCT, 66.7±7% for 10/10 URD, 64±13% for 9/10 URD, p=0.008), while no difference was observed in OS. Multivariate analysis confirmed significantly lower RI for 10/10 (HR 0.36, p<10-5, 95% CI:0.29-0.44) and 9/10 URD (HR 0.43, p<10-5, 95% CI:0.32-0.57) and higher NRM for 10/10 URD (HR 3.88, p<10-5, 95% CI:2.37-6.33) and 9/10 URD (HR 4.89, p<10-5, 95% CI:2.84-8.43) compared to ASCT. URD-SCT was associated with better LFS compared to ASCT (HR 0.57, p<10-5, 95%, CI:0.47-0.67 for 10/10 URD; HR 0.69, p=0.002, 95% CI:0.55-0.87 for 9/10 URD). 10/10 URD was associated with better OS compared to ASCT (HR 0.81, p=0.031, 95% CI:0.66-0.98) but no difference in OS was observed between 9/10 URD and ASCT (HR 1.02, p=0.87, 95% CI:0.79-1.31).Conclusion. In AML patients lacking an HLA-matched sibling donor URD-HSCT significantly reduces relapse risk and improves LFS. 10/10 URD showed better OS compared to ASCT in MV analysis in our series, while 9/10 URD impact on LFS didn't translate in better OS. In intermediate risk patients, in the absence of an HLA fully matched sibling or unrelated donor, autologous transplant may be considered as a valid option as ASCT results seem to overlap 10/10 URD outcome and to provide better survival compared to mismatch URD. Analysis is ongoing to better define which subpopulation of patients might benefit from each approach. [Display omitted] DisclosuresCraddock:Celgene: Consultancy, Honoraria, Research Funding; Pfizer: Speakers Bureau; Sunesis: Honoraria; Johnson and Johnson: Consultancy.

Refractory T-Cell Prolymphocytic Leukemia with JAK3 Mutation: In Vitro and Clinical Synergy of Tofacitinib and Ruxolitinib

▪T-cell prolymphocytic leukemia (T-PLL) is a rare hematologic disease characterized by a T-cell phenotype, rapid progression, and poor prognosis with median survival of less than a year. Alemtuzumab-based chemotherapy has increased the rate of complete remissions but these are often short-lived and allogeneic transplant is considered the only curative therapy. In recent studies, JAK3 activating mutations have been identified in T-cell cancers, with T-PLL having the highest rate of JAK3 mutations (30 - 42%). As such, T-PLL is a model disease for evaluating the utility of JAK3 inhibitors. We present a case of a 64 year old man with relapsed-refractory T-PLL. He was initially treated with alemtuzumab and obtained complete response and was consolidated with matched unrelated donor stem cell transplant. His disease stayed in remission for approximately 1.5 years before relapse, which was then treated with a clinical trial of romedepsin-lenalidomide (partial responses then progression at 6 months) and later alemtuzumab. Due to complications of myelosuppression and CMV reactivation, his treatment was interrupted leading to disease progression (Figure 1). The doubling time of lymphocyte count was approximately 20 days and over a span of 60 days the lymphocyte count rose from 8 x 109/L to 68 x 109/L. Exon sequencing showed a JAK3 mutation. The patient consented to and was treated with FDA-approved tofacitinib (initially 5 mg BID, increased to 10 mg BID after 15 days of treatment). An initial decrease in lymphocyte count was followed by progression. In vitro treatment of the patient's cells showed modest effects of tofacitinib and ruxolitinib as single agents, in the range of doxorubicin, but synergy between the agents (Figure 2). After 40 days of treatment with tofacitinib and with a lymphocyte count of 150 x 109/L, ruxolitinib (5mg BID) was added. Over the 60 days since dual inhibition was started, the lymphocyte count has stabilized. The patient has remained completely asymptomatic during treatment with tofacitinib and ruxolitinib. Neutrophil count has remained normal. Platelet count and hemoglobin have however declined from ~50 x109/L to ~30 x109/L and from 11 g/dL to 8.1 g/dL respectively, since the introduction of ruxolitinib. The stabilization in lymphocyte count confirms the clinical activity of JAK inhibitors in T-PLL as suggested by the presence of JAK3 mutations and by in-vitro assays. It also suggests clinical synergy between ruxolitinib and tofacitinib in this setting. Prospective studies of JAK inhibitors in PLL patients with formal dose-finding studies are needed. [Display omitted] [Display omitted] DisclosuresOff Label Use: Jak inhibitors in TCL. van Besien:Miltenyi Biotec: Research Funding.

The Combination of Cyclosporine and Mycophenolate Mofetil Is Less Effective Than Cyclosporine and Methotrexate in the Prevention of Acute Graft-Versus Host Disease after Allogeneic Stem Cell Transplantation from Unrelated Donors

Allogeneic Stem cell transplantation (SCT) from unrelated donors is a potential curative approach for a variety of hematological malignancies. Acute graft-versus-host disease (GVHD) is a major treatment-related complication. Several regimens for GVHD prevention have been explored, but no regimen has shown superiority over the others. We performed this retrospective analysis to compare outcomes following two of the most frequently used regimens, the combination of cyclosporine A and a short course of methotrexate (MTX group) and the combination of cyclosporine A and mycophenolate mofetil (cellcept, CC group). The study included 472 patients (pts) given unrelated donor transplant over an 11 year period in a single institution. The median age was 55 years (range, 18-76). The diagnoses included acute leukemia/MDS (66%), lymphoproliferative diseases (including lymphoma and myeloma, 24%), chronic myeloproliferative disorders (including CML, 7%) and non-malignant disorders (3%). The status at SCT was early (28%), intermediate (24%) and advanced (47%) according to CIBMTR criteria. The conditioning regimen was myeloablative (MAC, 19%), reduced-intensity (RIC, 39%) and reduced-toxicity myeloablative (41%). All pts were given ATG during conditioning. 97% of all pts had PBSC as the stem cell source for SCT. 71% had a 10/10 HLA match and 29% had ≤9/10. 13% had a comorbidity index >2. In all, 314 pts were in the MTX group and 158 in the CC group. The CC group included older pts (median age 57 Vs. 52 years, respectively, P=0.002), a lower percentage had MAC (9% Vs. 24%, P=0.005), more pts had lymphoproliferative disease and less acute leukemia (P=0.02). More pts had advanced disease at SCT (63% Vs. 37%, P=0.001) and more had a high comorbidity score (18% Vs. 11%, P=0.05). Engraftment was faster after CC, day 11 vs 14, respectively (P=0.001). Acute GVHD grade II-IV occurred in 47% (95% CI, 40-56) vs 27% (22-33), P=0.001). Acute GVHD grade III-IV occurred in 28% (95% CI, 21-37) vs 12% (9-17), P=0.001). Multivariate analysis (MVA) identified HLA mismatch (HR, 2.5, P=0.001), RIC (HR 0.6, P=0.03) and the use of CC in GVHD prevention (HR 2.3, P=0.001) as risk factors for acute GVHD. Chronic GVHD was 30% (26-34) and was similar after CC and MTX. With a median follow-up of 52 months (range, 5-151) 175 pts are alive, 145 died of treatment related causes (NRM) and 152 of relapse. 5-year NRM was 44% (37-53) and 24% (20-30) after CC and MTX, respectively (P=0.001). The difference was due to excess death due to GVHD with similar non-GVHD related NRM. MVA identified age>55 years (HR 1.5, P=0.04), less than 10/10 matching (HR 2.3, P=0.001), advanced disease (HR 2.0, P=0.001), high comorbidity score (HR 1.8, P=0.02) and the use of CC (HR 1.6, P=0.02) as independent factors predicting NRM. However, the CC and MTX group were not balanced in terms of risk factors, with the CC group including pts with a higher risk for acute GVHD and NRM. To minimize this potential bias we analyzed these outcomes on the basis of the intention to treat. During the years 2008-2009, the leading GVHD prevention regimen for unrelated donor SCT in our institution included CC, 90 of 101 pts transplanted in this period had CC (90%). During the other years CC was used according to the attending physician discretion in 68 of 371 SCT (18%). The group transplanted in 2008-9 was well matched with the other periods in all pt characteristics. Acute GVHD grade II-IV occurred in 50% (41-61) in the years 2008-9 when CC was used predominantly and 30% (25-35) in the other periods (P=0.006). Acute GVHD grade III-IV occurred in 27% (CI, 19-39) vs 15% (11-19), respectively (P=0.008). NRM was 34% (26-44) vs 30%, respectively (p=0.58). GVHD related death was higher in 2008-9 but non-GVHD death was lower, resulting in similar NRM. Relapse mortality was similar after CC and MTX. Among all pts, CC was associated with a lower 5-year overall survival, 28% (21-35) and 41% (35-46), respectively (P=0.005). However, with the time period intention to treat analysis, OS was identical, 36% (P=0.81). In conclusion, cyclosporine and CC is associated with faster engraftment and possibly with less organ toxicity than cyclosporine and MTX. However, it is associated with inferior prevention of acute GVHD, more GVHD related death and possibly with increased NRM. Cyclosporine and MTX should remain the standard GVHD prevention regimen for unrelated donor SCT.*AN and AS equally contributed. DisclosuresNagler:Novaratis Pharmaceuticals Corporation: Consultancy, Honoraria, Research Funding.

Comparison of Subcutaneous versus Intravenous Alemtuzumab for Graft-versus-Host Disease Prophylaxis with Fludarabine/Melphalan–Based Conditioning in Matched Unrelated Donor Allogeneic Stem Cell Transplantation

The objective of this study was to compare infusion-related reactions and outcomes of using subcutaneous (subQ) alemtuzumab versus intravenous (i.v.) alemtuzumab as graft-versus-host disease (GVHD) prophylaxis for matched unrelated donor stem cell transplantations. Outcomes include incidence of cytomegalovirus (CMV)/Epstein-Barr (EBV) viremia, development of CMV disease or post-transplantation lymphoproliferative disorder, fatal infections, acute and chronic GVHD, time to engraftment, relapse rate, and survival. We conducted a retrospective study of all adult matched unrelated donor stem cell transplantations patients who received fludarabine/melphalan with subQ or i.v. alemtuzumab in combination with tacrolimus as part of their conditioning for unrelated donor transplantation at New York-Presbyterian/Weill Cornell Medical Center from January 1, 2012 to March 21, 2014. Alemtuzumab was administered at a total cumulative dose of 100 mg (divided over days −7 to −3). Forty-six patients received an unrelated donor stem cell transplantation with fludarabine/melphalan and either subQ (n = 26) or i.v. (n = 20) alemtuzumab in combination with tacrolimus. Within the evaluable population, 130 subQ and 100 i.v. alemtuzumab doses were administered. For the primary outcome, ≥grade 2 infusion-related reactions occurred in 11 (8%) versus 25 (25%) infusions in the subQ and i.v. cohorts, respectively (P = .001). Overall, 12 injections (9%) in the subQ arm versus 26 infusions (26%) in the i.v. arm experienced an infusion-related reaction of any grade (P = .001). There were no significant differences between the subQ and i.v. arms in rates of reactivation of CMV/EBV, development of CMV disease or post-transplantation lymphoproliferative disorder, fatal infections, acute and chronic GVHD, relapse, or survival. Subcutaneous administration of alemtuzumab for GVHD prophylaxis was associated with fewer infusion-related reactions compared with i.v. administration in the SCT setting. Incidences of acute and chronic GVHD were similar between both arms. There was also no difference in reactivation of CMV/EBV viremia, development of CMV disease or post-transplantation lymphoproliferative disorder, fatal infections, relapse, or survival.

Acute myeloid leukemia developing in a granulocyte colony-stimulating factor-mobilized stem cell donor: A case report and review of the literature

We describe the first case of a FLT-3 mutated AML in a healthy donor, 3years after recombinant human granulocyte colony stimulating factor (rhG-CSF)-mobilized peripheral blood stem cell (PBSC) harvest. The patient had a myeloablative (MA) matched unrelated donor (MUD) stem cell transplant (SCT) for refractory AML. However, he experienced a secondary graft failure. He had a second non myeloablative (NMA) on day +75 from a second MUD. He achieved a complete neutrophil and platelet engraftment. After 4years of follow up, he is alive in complete remission with full second donor chimerism.

Diagnosis and management of childhood aplastic anaemia

Abstract Aplastic anaemia is a rare disorder in children. ∼20% of cases are inherited, whilst the rest are considered as acquired or idiopathic where no cause can be found. Diagnosis of the inherited causes of aplastic anaemia can be challenging but it is important for appropriate management and counselling. For idiopathic severe aplastic anaemia, a matched sibling donor haematopoietic stem cell transplant is the treatment of choice. If a matched sibling donor is not available, the options include immunosuppressive therapy with horse ATG and ciclosporin or unrelated donor haematopoietic stem cell transplant. Immunosuppressive therapy with horse anti-thymocyte globulin (ATG) is superior to rabbit ATG. Outcomes following matched unrelated donor haematopoietic stem cell transplantation are now similar to that of matched sibling donor haematopoietic stem cell transplant. The decision to proceed with immunosuppressive with ATG or unrelated donor stem cell transplant will depend on the likelihood of finding a matched unrelated donor and the differing risks and benefits that each therapy provides.

Agranulocytosis as a Part of Secondary Graft Failure after Allogenic Stem Cell Transplantation

Secondary graft failure after myeloablative allogeneic Stem Cell Transplantation (SCT), although rare, is a serious complication and usually requires a second allogeneic SCT to restore normal donor-derived hematopoiesis. Here, we are presenting a patient with acute myeloid leukemia who developed secondary graft failure following HLA 9/10 Ag-matched unrelated donor SCT. The clinical context and the marrow findings raised the suspicion of an immune-mediated mechanism to be the likely cause of graft failure. He received immunosuppressive therapy (Horse ATG, cyclosporine, corticosteroid) that resulted in restoration of full donor-derived hematopoiesis with essential normal peripheral blood counts, and thus obviating the need for a second allogeneic SCT.