ALBERT

Description: Hematopoietic stem cell transplantation (HSCT) is a curative therapy for a variety of hematologic malignancies. Recent studies have indicated the presence of donor-derived alloreactive NK cells as an additional factor influencing transplantation outcome, NK cells being regulated by signals delivered from multiple activating and inhibitory receptors. In the allogeneic HSCT setting, several studies considered donor-recipient HLA-I mismatch as the basis for NK alloreactivity. The implication of the KIR ligand incompatibility model is that donor’s NK cells exhibit the relevant inhibitory KIR for the self HLA-I ligands. It is known, however, that the KIR genes and the HLA genes segregate independently of each other in normal mendelian fashion. This allows the possibility that individuals lack HLA ligands for their KIR receptors and indicates that NK cells alloreactivity can occur also in HLA-matched or HLA-identical transplants. Recent investigations suggest that relapse and KIR-driven alloreactivity in the transplantation setting might be better predicted if the donor KIR genotype is considered in addition to the HLA genotype of the recipient. The aim of this study was to investigate at genetic level the prognostic impact of recipient HLA-I lacking for donor KIR on allotransplanted patients outcome. We analyzed donors KIR genotype and HLA genotype of 60 pediatric patients who received related (n.15) or unrelated (n.45) transplantation. When patients were grouped on the basis of the KIR gene type involved in the KIR/HLA-I mismatch, we did not observe any relapse in the group of patients characterized by mismatches involving only inhibitory KIR. On the contrary, all relapses were observed in patients showing at least one activating gene involved in the mismatch (p

Description: Isomorphic mutation of SBDS gene is the cause of Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have altered ribosome biogenesis and protein synthesis, two high-energy consuming cellular processes. The reported increment in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest a defect in the energy production in SDS cells. In this study, we analyzed the energetic metabolism in SDS cells and find that the oxygen consumption is impaired when it is induced by pyruvate/malate or succinate. This induces poor ATP production and AMP accumulation with a consequent alteration in the ATP/AMP ratio. Also respiratory chain activity was impaired because of faulty function of the complex IV; this defect is not dependent from impaired protein synthesis despite ribosome biogenesis and transduction defects in SDS. In fact, COX5A and Cox2, two subunits of Complex IV encoded respectively by a nuclear and mitochondrial gene, were expressed at normal levels. Impaired function of complex IV could be due to an increment of cytoplasmic calcium concentration that inhibits complex IV activity. Energetic stress induces changes in cellular metabolism, stimulating or inhibiting a network of molecules involved in regulation of energetic balance, such as AMPK and mTOR. In SDS cells as consequence of energetic stress, AMPK is hyper activated and the glycolytic pathway stimulated. Surprisingly, we found that also the AKT/mTOR pathway is aberrantly hyper activated since both these proteins are hyper-phosphorylated. We can speculate that hyper activation of mTOR is a way through which SDS cells support the energy defect and protein synthesis. All these defects were recovered when the SDS cells were complemented with SDS gene. Finally, leucine is an essential amino acid that induces cell proliferation and protein synthesis, restored OXPHOS and ATP synthesis, reduced the cytoplasmic calcium concentration and the AMPK and AKT/mTOR activity, and improved in vitro erythropoiesis from SDS individuals pointing to leucine as potential tool helpful to sustain deranged energetic metabolism and erythropoiesis in SDS patients. In conclusion, we report for the first time that SDS cells suffer of energetic stress and severe respiratory defect that is related to faulty SBSD protein. These defects are compensated by an enhanced activation of AMPK, glycolysis and mTOR/Akt pathways, which appear to adequately support protein synthesis. A pivotal role in the maintenance of this altered metabolism could be played by altered calcium homeostasis. Noteworthy biochemical defects might be largely corrected by leucine which also favourably affects in vitro erythropoiesis thus pointing to biochemical defects as important determinant for impaired hematopoiesis od SDS. Disclosures Dufour: Pfizer: Consultancy.

Description: Introduction Hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is an unpredictable, potentially life-threatening complication of chemotherapy (CT) given as conditioning for hematopoietic stem cell transplantation (HSCT), or as primary treatment. Severe hepatic VOD/SOS, traditionally defined by occurrence of multi-organ dysfunction/failure (MOD/MOF), may be associated with mortality rates 〉80%. In the European Union, defibrotide is approved for treatment of severe VOD/SOS post-HSCT. It is not approved in the United States, but is available through an expanded-access program. Here, we report the results of an Italian therapeutic use program, defibrotide treatment protocol (TUT), in which defibrotide was provided upon physician request for treatment of patients with VOD/SOS. Methods This was a multicenter, single-arm, open-label program of defibrotide treatment in patients with hepatic VOD/SOS, with or without MOD/MOF, from 2010-2014. Patients were eligible if they were diagnosed with VOD/SOS having met ≥2 of the following criteria: bilirubin (〉2 mg/dL), ascites, unexplained weight gain 〉5% above baseline (weight on day 1 of HSCT conditioning or CT), or hepatomegaly. Patients with biopsy-proven VOD/SOS were also eligible. Exclusion criteria were use of anticoagulants (beyond those for IV line maintenance), significant uncontrolled acute bleeding (transfusions after dialysis were allowed), pregnancy, and hemodynamic instability requiring 〉2 vasopressor drugs. MOD/MOF was defined as renal (creatinine 〉3x baseline, creatinine clearance or glomerular filtration rate

Description: Abstract 1207 Poster Board I-229 Patients. Data from 100 patients with acquired severe aplastic anemia (SAA) undergoing an alternative donor transplant, were analyzed. Patients were prepared with a combination of fludarabine (30 mg/m 2×4), cyclophosphamide (300 mg/m 2×4), antithymocyte globulin (3.75 mg/lgx4) (FCA) (n=52, median age 13 years), or FCA supplemented with low dose (2 Gy) total body irradiation (FCA-TBI), but with a lower dose of ATG (total 7.5 mg/kg) (n=48, median age 27 years). The donor was unrelated (n?87) or a one antigen mismatched family donor (n=13). GvHD. Acute graft versus host disease (GvHD) grade III-IV was seen in 13% and 7% ; extensive chronic GvHD was recorded in 1 FCA patient and in 4 patients receiving FCA-TBI. Graft failure. Rejection/graft failure was seen in 17 patients, equally distributed in the two groups: 9/17 patients survive long term, 3 with autologous recovery, and 6 after a second transplant.. As to predictors of graft failure, patients with a longer interval from diagnosis to transplant (〉 2 years) had a trend for a higher risk of GF (22%) as compared to patients grafted

Description: Introduction Hepatic veno-occlusive disease, also called sinusoidal obstruction syndrome (VOD/SOS), is a potentially life-threatening complication of conditioning for hematopoietic stem cell transplantation (HSCT) and is associated with patient and transplant-related risk factors, such as prior therapies, underlying diagnoses, and conditioning regimen. Unpredictable in its occurrence and severity, VOD/SOS is clinically characterized by painful hepatomegaly, hyperbilirubinemia, ascites, and weight gain. Overall estimated prevalence is 14% post-HSCT, while rates in some high-risk populations (eg, osteopetrosis or prior gemtuzumab ozogamicin) are 〉60% (Wadleigh M et al. Blood. 2003;102:1578-82; Corbacioglu S et al. Bone Marrow Transplant. 2006;38:547-53). Evidence suggests that defibrotide stabilizes endothelial cells, with direct and endothelial-cell mediated restoration of the thrombo-fibrinolytic balance. Defibrotide is approved in the European Union for the treatment of severe hepatic VOD/SOS in patients receiving HSCT, and is available in the United States through an expanded-access study. In a previously reported randomized clinical trial, defibrotide prophylaxis for VOD/SOS in high-risk pediatric patients undergoing HSCT reduced the overall incidence of VOD/SOS by day +30 post-HSCT. Here we report novel subgroup analyses of VOD/SOS incidence from this trial in patients with specific VOD/SOS risk factors at baseline. Methods This was a phase 3, multicenter, open-label, randomized, controlled trial in patients aged 5% weight gain. Patients were randomized to standard care with or without defibrotide prophylaxis dosed at 25 mg/kg/day in 4 divided infusions of 6.25 mg/kg. Osteopetrosis was a stratification variable. Defibrotide began the same day as HSCT conditioning and continued for 30 days post-HSCT, or ≥14 days for patients discharged from hospital before day +30 post-HSCT. Control patients who developed VOD/SOS received defibrotide treatment. The primary endpoint was incidence of VOD/SOS at day +30 post-HSCT. Results The intent-to-treat population included 356 patients: 180 randomized to defibrotide prophylaxis and 176 in the control group. Mean (SD) age was 6.6 (5.3) years, and 40.7% of patients were female. Demographic and clinical characteristics, including VOD/SOS risk factors (Table), were well-matched in the defibrotide and control groups. The most common risk factors among all patients were conditioning with busulfan and melphalan (58%), preexisting liver disease (27%), and second myeloablative transplantation (13%). VOD/SOS occurred by day +30 post-HSCT in 22 (12%) patients in the defibrotide prophylaxis group vs 35 (20%) patients in the control group. For the stratification variable, osteopetrosis, rates of VOD/SOS were 14% in the defibrotide prophylaxis arm and 67% in the control arm (Table). Differences in rates of VOD/SOS were lowest for adrenoleukodystrophy (no cases) and prior abdominal irradiation (11% vs 13%, respectively) (Table). Conclusions Across risk-factor subgroups, the rate of VOD/SOS was lower in patients receiving defibrotide compared with controls (except adrenoleukodystrophy: no VOD/SOS in either group). In particular, rates of VOD/SOS by day +30 were reduced by ≥50% in the defibrotide arm vs the control arm among patients with osteopetrosis, hemophagocytic lymphohistiocytosis, second myeloablative transplantation, and prior gemtuzumab treatment. Although the total numbers of patients with these risk factors were small, these between-group differences are of clinical interest and should be further explored. Table. Risk Factor Defibrotide (n=180) Control (n=176) Total n VOD/SOS incidence (n=22; 12.2%) n (%*) Total n VOD/SOS incidence (n=35; 20.0%) n (%*) Adrenoleukodystrophy 1 0 (0) 1 0 (0) Osteopetrosis 7 1 (14) 6 4 (67) Prior abdominal irradiation 9 1 (11) 8 1 (13) Hemophagocytic lymphohistiocytosis 10 0 (0) 15 6 (40) Prior gemtuzumab 11 2 (18) 5 2 (40) Allogeneic HSCT for leukemia 17 2 (12) 11 2 (18) Second myeloablative transplantation 25 2 (8) 23 4 (17) Pre-existing liver disease 41 6 (15) 54 12 (22) Busulfan/melphalan conditioning 106 15 (14) 99 17 (17) *Percent of patients with VOD/SOS. Support: Jazz Pharmaceuticals Disclosures Corbacioglu: Gentium S.p.A.: Consultancy, Honoraria. Off Label Use: Defibrotide is an investigational treatment for hepatic veno-occlusive disease/sinusoidal obstruction syndrome in the United States.. Bader:Amgen: Consultancy; Medac: Other: Institutional grants; Neovii: Other: Institutional grants; Riemser: Other: Institutional grants; Novartis: Consultancy; Jazz Pharmaceuticals: Consultancy.

Description: After hematopoietic transplantation invasive aspergillosis is one of the most lethal infections. Susceptibility to invasive aspergillosis may be due to GvHD and its prophylaxis and treatment in T cell-replete transplants, and to T-cell-depletion in haploidentical transplants. Studies in mice and humans show that adaptive T-helper type-1 immune effector mechanisms are involved in control of invasive aspergillosis (Hebart et al. Blood, 2002; Cenci et al. J Immunol, 2000). In vivo T-cell priming induced by DCs pulsed with A. fumigatus conidia protects bone marrow transplanted mice from invasive aspergillosis (Bozza et al. Blood, 2000). This study monitored recovery of anti-Aspergillus immune competence in recipients of T cell-replete matched transplants and of T cell-depleted matched or haploidentical transplants for acute leukaemia. Patients: 32 pediatric recipients of matched T-replete transplants from unrelated donors (n=21), unrelated cord blood (n=2), and matched siblings (n=9) (median age: 10.5 years; range: 0.5–24); 20 adult recipients of matched T cell-depleted transplants (median age: 43 years; range 18–65), and 46 adult recipients of haploidentical transplants (median age: 34 years; range: 9–64). In all we monitored recovery of CD4+ T-cells and Aspergillus-specific CD4+ T-cells (by LDA) monthly for 18 months after transplant. Total CD4+ T-cell counts were higher after T-replete matched than after T-depleted matched or haploidentical transplant. At 9 months, CD4+ cells were: 1332±337 in T-cell replete transplant recipients, 364±62 in T cell-depleted matched transplant recipients, and 218±186 in haploidentical transplant recipients (p=0.000). Incidence of acute GvHD 〉 grade II was 60% after T-replete transplantation, 0% after T cell-depleted matched and 9% after haploidentical transplantation. Aspergillus-specific T cells were first detected 15–18 months after T-replete matched transplantation (when immune suppressive GvHD prophylaxis/therapy was being withdrawn); 7–9 months after T cell-depleted matched transplantation and 9–12 months after haploidentical transplantation (p=0.000). Incidence of invasive aspergillosis was 21%, with a 10% mortality after T-replete transplants, 0% after T cell-depleted matched (p=0.000) and 7% with 4% mortality after haploidentical transplants (p=0.000). Although T cell counts were significantly higher after T-replete transplants their function appeared to be impaired by post-transplant immune suppression/GvHD. T-replete transplants were associated with a higher incidence of invasive aspergillosis and aspergillosis-related deaths. Specific Aspergillus immune competence recovered faster after T cell-depleted transplants, whether matched or haploidentical. These results show that T-cell depletion and no post-transplant immune suppression may provide a better pattern of immune recovery than T cell-replete transplantation and challenge the widely held belief that immune recovery after T cell-depleted transplants, particularly the haploidentical, is unduly delayed.

Description: Abstract 3344 Poster Board III-232 Background: Hepatic VOD is a life-threatening complication following SCT with a high incidence in children. Development of VOD is one of the most common causes of early death after SCT. Busulfan (BU), an alkylating agent with a very narrow therapeutic index is a commonly used conditioning agent in pediatric stem cell transplantation (SCT) with a strong correlation between AUC and both efficacy and toxicity. Oral BU (poBU) has significant age-related and interpatient pharmacokinetic differences and was linked with an increased risk for VOD. IV busulfan (ivBU) yielded promising results in some studies to be associated with low toxicity profile, especially with a reduced incidence of VOD. Methods: Patients 2 mg/dL, hepatomegaly, ascites and/or unexplained weight gain 〉 5%). VOD was assessed by physical exam; hepatomegaly and ascites were confirmed by ultrasound. A blinded IRC of 3 expert hematologists confirmed the diagnosis of VOD. Although the study was not powered to assess mortality, a composite score was assessed as a secondary endpoint that incorporated VOD-associated toxicity (respiratory failure, renal failure, encephalopathy) and mortality. The additional analysis of the influence of BU on VOD was not planned and is therefore explorative. Results: 360 pts were enrolled between January 2006 and January 2009 by 28 centers in the EU and Israel. An Intent-to-Treat (ITT) analysis was performed on all pts who signed informed consent (n=356). 251 (71%) pts from the ITT population were conditioned with BU (64% ivBU; 36% poBU). 202 (55%) were treated with BU and Melphalan (MEL) (60% ivBU; 40% poBU). In 49 (14%) BU was used without MEL (80% ivBU; 20% poBU). In children

Description: Severe hepatic VOD/SOS is a potentially life-threatening complication of HCT conditioning that may also develop after high-dose chemotherapy. The most severe form of VOD/SOS is often accompanied by multi-organ failure (MOF) and is associated with a mortality rate of 〉80% when managed with supportive care alone. As part of the marketing authorization in Europe, there was an obligation to set up a disease registry of patients with severe VOD/SOS post-HCT who were treated with defibrotide. The goal of this registry was to collect safety and outcome data and assess patterns of defibrotide utilization in the post-approval setting. This multicenter, multinational, prospective observational study (NCT03032016) was performed by the European Society for Blood and Marrow Transplantation (EBMT). The study included patients with severe VOD/SOS post-HCT who were treated with defibrotide and enrolled from April 2015 to July 2018. Participating centers were members of the EBMT. Physicians registered patients diagnosed with severe VOD/SOS, as assessed by the investigator using classical/standard criteria (including but not limited to hyperbilirubinemia, hepatomegaly, ascites, and weight gain 〉5%), who consented to participate in the study. In addition, patients who were prescribed defibrotide for purposes other than the approved indication (eg, VOD/SOS prophylaxis, treatment of non-severe VOD/SOS or thrombotic microangiopathy) and consented to participate were registered and information collected. There were no specific exclusion criteria; however, treating physicians were alerted to contraindications, special warnings, and precautions detailed in the defibrotide summary of product characteristics. After inclusion, patient information was collected from participating centers at 100 days, 6 months, and 12 months post-HCT. The primary objective was to assess the incidence of specific serious adverse events (SAEs) of interest, which were hemorrhage and site of bleeding, hypotension, coagulopathy, allergic or hypersensitivity reactions, injection-site reaction, infection and septicemia, and thromboembolic events. Secondary endpoints included Day 100 survival, and overall rate of VOD/SOS (and MOF, if present) resolution (based on standard criteria). Summary statistics were calculated for baseline data and safety variables; outcome analyses are descriptive. Here we report an analysis of data with a cutoff of June 18, 2019. Database lock is planned for October 2019, and the presentation will be updated to include the final data. A total of 61 patients with severe VOD/SOS were included; MOF was diagnosed at registration in 34 (56%) patients. The median age of patients with severe VOD/SOS was 14.4 (range: 0-68) years, 34 (56%) aged

Description: Abstract 653 Background: Hepatic VOD is a life-threatening complication following SCT with a particularly high incidence in children. Development of VOD is one of the most common causes of early death after SCT. DF (Gentium SpA), a polydisperse oligonucleotide, demonstrates a protective effect on vascular endothelial cells in vitro. Small non-randomized trials to assess DF for the prophylaxis of VOD were promising without significant anticoagulant effects. Methods: Eligibility criteria included pts 2 mg/dL, hepatomegaly, ascites and/or unexplained weight gain 〉 5%). VOD was assessed by physical exam; hepatomegaly and ascites were confirmed by abdominal ultrasound. A blinded independent review committee of 3 expert hematologists confirmed the diagnosis of VOD. Although the study was not powered to assess mortality, a composite score was assessed as a secondary endpoint that incorporated VOD-associated toxicity (respiratory failure, renal failure, encephalopathy) and mortality. Incidence and severity of graft versus host disease (GvHD) was assessed. As the true incidence of VOD in this population was unknown, the trial incorporated a planned adaptive interim analysis to be reviewed by an independent DSMB. Results: Based on the recommendations of the DSMB, 360 pts were enrolled between January 2006 and January 2009 by 28 centers in the EU and Israel. An Intent-to-Treat (ITT) analysis was performed on all randomized pts who signed informed consent (DF: 180; control: 176). Median age was 4.8 years; 24% infants, 52% children (ages 2-11 years) and 23% adolescents. 41% were female, 59% male. 68% were allo-, 31% auto-SCT. There were no significant differences between the two arms in disease types or risk factors. Ninety-three percent (93%) of the patients completed the primary endpoint at day +30. In the ITT analysis, 12% (22/180) of the pts of the DF arm and 20% (35/176) of the control group developed VOD by D+30 (P=0.054); in the PP analysis, the VOD incidence was 12% (20/164) vs 21% (35/169) (P=0.037). VOD was experienced by 23% of the infants, 14% of the children and 13% of the adolescents. The composite score (assessing VOD morbidity and mortality) was significantly in favor of the DF arm (P=0.034). Significantly less acute GvHD by D+100 was reported in the DF pts (32% (57/180) vs 43% (75/176); P=0.023 by Wilcoxon test). Observation of VOD in either arm led to a higher mortality: mortality of pts with VOD equaled 24.6% (14/57) compared to 7% in pts without VOD (21/299). Renal failure was observed in 1% (2/180 pts) of DF pts vs 6% (10/176) of the control (P=0.017); respiratory failure was observed in 7% vs 9% (NS); and encephalopathy in 1% vs 2% (NS). SAEs were experienced by 58% of the DF pts vs 59% of the control, including infections (24% vs 27%) and respiratory disorders (12% vs 9%); 9 hemorrhagic events were seen in the DF arm compared to 21 in the control. Conclusions: This Phase II/III randomized study demonstrates the efficacy and safety of DF in preventing VOD in pediatric pts at high risk of VOD. Use of prophylactic DF results in a 40% reduction in the incidence of VOD. Consistent with the role of DF in endothelial protection, both renal failure and acute GvHD were significantly lower in the DF arm. Safety of DF was confirmed by lack of significant toxicity (including hemorrhage). DF can be recommended for the prevention of VOD in this high risk population. Disclosures: Corbacioglu: Gentium S.p.A.: Consultancy, Research Funding. Massaro:Gentium S.p.A.: Consultancy. D'Agostino:Gentium S.p.A.: Consultancy, Membership on an entity's Board of Directors or advisory committees. Hoyle:Gentium S.p.A.: Employment. Iacobelli:Gentium: Employment.

Description: Sera of 658 patients who had completed treatment for pediatric malignancy were analyzed by a second-generation enzyme-linked immunosorbent assay and recombinant immunoblot assay test to assess the prevalence of hepatitis C virus (HCV)-seropositivity. All HCV-seropositive patients underwent detailed clinical, laboratory, virologic, and histologic study to analyze the course of HCV infection. One hundred seventeen of the 658 patients (17.8%) were positive for HCV infection markers. Among the 117 anti-HCV+ patients, 41 (35%) were also positive for markers of hepatitis B virus infection with or without delta virus infection markers, 91 (77.8%) had previously received blood product transfusions, and 25 (21.4%) showed a normal alanine aminotransferase (ALT) level during the last 5-year follow-up (11 of them never had abnormal ALT levels). The remaining 92 patients showed ALT levels higher than the upper limit of normal range. Eighty-one of 117 (70%) anti-HCV+ patients were HCV-RNA+, with genotype 1b being present in most patients (54%). In univariate analysis, no risk factor for chronic liver disease was statistically significant. In this study, the prevalence of HCV infection was high in patients who were treated for a childhood malignancy. In about 20% of anti-HCV+ patients, routes other than blood transfusions are to be considered in the epidemiology of HCV infection. After a 14-year median follow-up, chronic liver disease of anti-HCV+ positive patients did not show progression to liver failure.