Mesenchymal Stromal Cells (MSCs) Experience in France to Prevent Graft Failure after Hematopoietic Stem Cell Transplantation: A Retrospective Study from the MSCs/CTL Group of the Francophone Society SFGM-TC

Graft failure occurs in 3-5% of hematopoietic stem cell transplantations (HSCT) and raises up to 10% for mismatched HSCT. It is a severe complication leading to lethal infections or bleedings. Several studies reported that engraftment could be improved by mesenchymal stromal cells (MSCs) infusion. Those cells are multipotent cells capable of differentiation in at least 3 lineages (adipocytes, chondrocytes and osteocytes) and of supportive effects on hematopoiesis. This treatment is considered as an Advanced Therapy Medicinal Product in France and there is currently no authorization for its use outside of clinical trials. We retrospectively analyzed the demands from HSCT French centers to the expert committee of the SFGMTC and the French regulatory agency (ANSM), since 2014, in order to ask for MSCs exceptional recourse for patients with graft failure. Nine requests for MSCs were made. One patient did not receive any MSCs because MSCs bag was contaminated, another one had an haploidentical transplantation without MSCs instead. Finally, 7 patients received 1 or 2 infusions of MSCs (Table). Median age was of 6 years (4-23), sex ratio was of 2,5. Two patients (29%) had an acute lymphoblastic leukemia (ALL) and 5 patients (71%) had an aplastic anemia (idiopathic n=4, congenital n=1). Five patients had received one transplantation, and 2 patients had received two transplantations, followed by a primary graft failure (n=6) and a secondary graft failure (n=1). Only 2 patients had received a myeloablative conditioning regimen (MAC) for the first procedure, one chemo- and one TBI- based. The other 5 patients had received a reduced-intensity conditioning (RIC) regimen, 4 of them with 2 grays TBI. Two patients had received a cord blood unit and 5 bone marrows from 1 sibling, 3 haploidentical and 1 mismatched donors. Only 2 patients had received antithymoglobulins in their previous regimen. Engraftments failed despite a median richness of 5,14.106 CD34 cells/kg/bone marrow graft (1,84-9,5) and of 1,25.105CD34 cells/kg/cord blood unit (1,2-1,3). Median delay between first HSCT with graft failure and MSCs infusion was of 2 months (1-32). To prepare last HSCT,six patients received a reduced intensity conditioning regimen with 2 grays TBI (Baltimore), and one patient received a myeloablative, chemo-based, regimen, with antithymoglobulins. Three patients received a graft from the same previous donor. Six patients received a haploidentical graft (5 bone marrows, 1 peripheral blood stem cells), and 1 received bone marrow from a mismatched donor. Median number of CD34+ cells was of 9,02.106/kg (1,61-12,43). All MSCs were from 8 pooled donors (OBNITIX®) except for one patient who received MSCs from a relative donor (which was different from the HSCT donor). All infusions were well tolerated and made on the same day as HSCT, apart from one patient who received MSCs for a secondary graft failure on day 228 post-transplantation, followed by an infusion of CD34+ cells on day 231, and a second infusion of MSCs on day 259. Mean dose of MSCs was of 1,72.106/kg (1,25-3,1). Median time for neutrophil recovery (neutrophils over 0.5 G/L) and platelet recovery (platelets over 50 G/L) on 3 consecutive days was respectively of 23 days (10-34) and 35 days (26-238). At day 30, 5 patients (71%) had a full donor chimerism. Only one patient presented a graft failure leading to a third HSCT. No secondary graft failure occurred after a median follow-up of 13 months (4-104). At last follow-up, none of the patients who achieved platelet and neutrophil recovery required neither blood or platelets transfusion nor thrombopoietin receptor analogs. Infusion of MSCs at the time of HSCT to prevent graft failure was safe and effective for 6/7 patients. Larger prospective trials are necessary to confirm MSCs impact on engraftment and graft function. Table Disclosures Dalle: AbbVie Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria; Jazz Pharmaceuticals: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Orchard: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Medac: Consultancy, Honoraria; Bellicum: Consultancy, Honoraria; Sanofi-Genzyme: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; bluebird bio: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees. Rubio:Medac: Consultancy; Gilead: Honoraria; MSD: Honoraria; Novartis: Honoraria; Neovii: Research Funding.

Download Full-text

Effectiveness of Reduced Toxicity Conditioning Regimen with Intravenous Busulfan Plus Pentostatin (BUPENT) in Patients Older Than 50 Years with Advanced Hematologic Malignancies.

Blood ◽

10.1182/blood.v114.22.3331.3331 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3331-3331

Author(s):

Tulio E. Rodriguez ◽

Mala Parthasarathy ◽

Scott E. Smith ◽

David H. Vesole ◽

Zachary M. Earley ◽

...

Keyword(s):

Overall Survival ◽

Stem Cell ◽

High Risk ◽

Stem Cell Transplantation ◽

Board Of Directors ◽

Graft Failure ◽

Conditioning Regimen ◽

Advisory Committees ◽

Reduced Toxicity

Abstract Abstract 3331 Poster Board III-219 Introduction Current data suggests that recipient age above 50 is associated with an inferior outcome after myeloablative allogeneic stem cell transplantation (SCT). Overall survival (OS) of 31%, and transplant related mortality (TRM) of 17% at 100 days have been reported in this population (Ditchkowski, et al 2005; Yanada, et al. 2004). Encouraging results are observed with non-myeloablative conditioning regimens. However, for patients with a high relapse risk, this approach may not be sufficient to achieve long term disease control. In these cases, a reduced toxicity, yet ablative stem cell transplantation (RT-SCT) may give adequate time to the transplanted cells to mature and mount an immune-mediated antitumor response. This study evaluated the outcome after RT-SCT using a conditioning regimen consisting of intravenous busulfan (Bu) and pentostatin (Pent). Methods Consented adult patients up to 70 years with a fully-matched related (MRD) or unrelated donor (MUD) were screened for enrollment. Conditioning consisted of Bu 1.6 mg/kg every 12 hours days -7 to -4, and Pent 4 mg/m2 on day -3 and -2 prior to stem cell infusion on day 0. GVHD prophylaxis was methotrexate 10 mg/m2 on day 1, and 5 mg/m2 on days 3, and 6. Tacrolimus was started on day -2, and then tapered over 1 month after day +100. Characteristics Twenty six patients were analyzed. Male to female ratio was 1:1. Stem cell source was from MRD in 15 patients and MUD in 11. Median age was 62, with 92% of patients being older than 50 years. Indications for treatment were AML (35%), MDS (42%), Refractory CLL (23%), Relapsed NHL (12%), and Philadelphia (+) ALL (4%). All AML patients were high risk either due to poor cytogenetic, transformation, or relapse and only two of them were transplanted in first complete remission. MDS patients were RAEB (36%), secondary MDS (36%), or multilineage dysplasia (18%). Two patients had prior autologous transplants. Results No graft failure was observed. All patients achieved neutrophil (NEU) engraftment. Two patients expired prior to platelet (PLT) engraftment. Median engraftment days for NEU and PLT were 13 days. At a median follow up of 25 months, the OS and progression free survival for the entire group was 40% and 38% respectively. The OS in the MRD group was 58%. TRM at 100 days was seen in one patient (4%) due to veno-occlusive disease (VOD). Limited chronic GVHD was the most common observed toxicity (54%), followed by diarrhea (30%) and mucositis (23%). Mucositis was mainly grade 1 (8%) and grade 2 (8%). No grade 3 mucositis was observed. There was only one case of VOD and one case of acute GVHD. Conclusion To our knowledge, this is the first report of a RT-SCT using BuPent. This study demonstrates the efficacy of the regimen in patients older than 50 years. No graft failure was observed and the regimen related toxicity was acceptable in this high-risk population. The overall survival of 40% at a median follow up of 25 months compares favorably with prior reports of myeloablative allogeneic stem cell transplatation in patients older than 50 years. This regimen provides an exciting opportunity to extend the benefits of allogenic transplant to an older population, and warrants replication with larger controlled trials. Disclosures Rodriguez: Otsuka: Membership on an entity's Board of Directors or advisory committees, Research Funding. Vesole:Amgen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Celgene: Speakers Bureau; Millenium: Speakers Bureau; Centocor Ortho Biotech: Speakers Bureau.

Download Full-text

Allogeneic Hematopoietic Stem Cell Transplantation for Acute Myeloid Leukemia Patients in First Complete Remission: Significant Impact of the Interval Between Diagnosis and Transplantation on Different Outcomes

Blood ◽

10.1182/blood.v126.23.5517.5517 ◽

2015 ◽

Vol 126 (23) ◽

pp. 5517-5517 ◽

Cited By ~ 1

Author(s):

Stéphanie Ducreux ◽

Mohamad Sobh ◽

Stéphane Morisset ◽

Marie Balsat ◽

Xavier Thomas ◽

...

Keyword(s):

Board Of Directors ◽

Median Time ◽

Myeloid Leukemia ◽

Conditioning Regimen ◽

Inclusion Criteria ◽

Advisory Committees ◽

Hematopoietic Stem ◽

First Complete Remission ◽

Acute Myeloid

Abstract Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the main therapeutic option for most patients with high risk acute myeloid leukemia (AML). In order to determine whether time between diagnosis and allo-HSCT could have any impact on transplant outcomes, we screened 700 consecutive adult AML patients diagnosed between January 2007 and June 2014 at the Lyon Sud Hospital transplant center. Inclusion criteria were: (1) newly diagnosed AML in patients with age ≤ 65 years, (2) AML classified in the intermediate-2 and unfavorable risk groups according to the Acute Leukemia French Association (3) patients fit for receiving chemotherapy (4) patients candidates for allo-HSCT and in first complete remission (CR1) at transplantation. Two hundred and one patients met the inclusion criteria and were enrolled in the study. Among them, 137 (68%) received allo-HSCT of whom 83 (41%) only received HSCT in CR1 after a median time of 143 days (range: 69-265) from diagnosis. We collected within this interval different delays for donor search, including patients HLA typing and time to unrelated donor identification when a sibling donor was not available. Patients were split into 2 groups based on their time to transplant. An "early transplant group" included 28 (33%) patients transplanted after a median time of 108 days (range: 69-133) after diagnosis. The other 55 (67%) patients transplanted after a median time of 163 days (range: 134-265) were qualified as "late transplant group". Patients and transplantation characteristics according to the timing of transplantation are shown in table 1. After a median follow-up of 16 months (range: 0-60) the 5-year probability of overall survival (OS) and disease-free survival (DFS) for the whole population were respectively, 63.4% and 48.3%. The cumulative incidences of non-relapse mortality (NRM) at 1 and 5 years were constant at 17.5%. The multivariate analysis using proportional hazards modeling showed that conditioning regimen and sex mismatching were independent prognostic factors for DFS, with no significant impact on OS. To evaluate the long term impact of transplantation timing on OS and DFS, we performed a landmark analysis for patients surviving at 1 year post-allo-HSCT. This analysis showed that patients in the early transplant group had a higher probability of OS at 3 and 5 years with 100% survival respectively compared to the late transplantation group with 85.5% and 79.4% respectively (p=0.09); accordingly, we found a significant difference in terms of DFS with 100% probability at 3 and 5 years for the early transplantation group compared to 80% and 56% respectively in the late transplantation group (p=0.02). This difference in terms of OS and PFS was still valid after stratification on the type of conditioning regimen. These results confirm the important impact of allogeneic HSCT timing in high-risk AML patients, early allo-HSCT for patients transplanted in CR1 is associated with a better OS and a very significant benefit in terms of DFS. Further analyses are ongoing including disease monitoring from diagnosis to the last follow-up to identify the potential of transplantation timing on the graft versus leukemia effect. Table 1. Table 1. Disclosures Nicolini: Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Ariad Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Download Full-text

Alternative Donor Hematopoietic Stem Cell Transplantation for Sickle Cell Disease in Europe

Blood ◽

10.1182/blood-2018-99-111129 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 4645-4645 ◽

Cited By ~ 2

Author(s):

Barbara Cappelli ◽

Graziana Maria Scigliuolo ◽

Fernanda Volt ◽

Selim Corbacioglu ◽

Josu de la Fuente ◽

...

Keyword(s):

Board Of Directors ◽

Research Funding ◽

Graft Failure ◽

Acute Gvhd ◽

Chronic Gvhd ◽

Conditioning Regimen ◽

Advisory Committees ◽

Hematopoietic Stem ◽

Gvhd Prophylaxis ◽

Alternative Donor

Abstract Hematopoietic stem cell transplant (HSCT) from an HLA identical sibling is a well-established curative therapy for sickle cell disease (SCD). HSCT from an unrelated donor is a treatment option, but the likelihood of finding a donor varies according to ethnicity and results are still limited. HLA haploidentical relatives can be alternatively used but, to date, only small series of patients have been described. We report outcomes of patients (pts) transplanted with related haploidentical (Haplo) or unrelated (UD) donors grafts and reported to EBMT/EUROCORD databases. Sixty four pts transplanted in 22 EBMT centers between 1991 and 2017 were retrospectively analyzed. Pts were described according to the donor type: haploidentical (n=40) and unrelated (n=24) [adult UD n=19; cord blood (CB) n=5]. The objective of the study was to describe alternative donor transplants for SCD in Europe without performing comparison analyses due to the size and heterogeneity of the groups. Primary endpoint was 3-year overall survival (OS). Median follow-up (FU) was 28 months (range: 1.6-156) [29.5 months (range: 2.1 - 133.5) for Haplo and 24.6 (range: 1.6 - 156) for UD]. Median age at HSCT was 14.2 years (range: 3-31.7) in Haplo and 11.8 (range: 2.1-42.8) in UD, with a predominance of children (<16 years) in both groups (23/40 and 19/24, respectively). Before HSCT, 68% of overall pts were treated with hydroxyurea and 62% received more than 20 red blood cell (RBC) units. RBC alloimmunization occurred in 14% of transfused pts. In both groups, vaso-occlusive crisis and cerebral vasculopathy were the most frequent SCD complications and the main indications for HSCT. Other complications were acute chest syndrome (44%), liver disease (31%) and infection (23%). In Haplo, median year of transplant was 2014 (range: 1991-2017) and in UD 2011 (range: 2004-2015). In Haplo, two major protocols were used: (1) post -transplant cyclophosphamide (PTCY) with G-CSF primed bone marrow (BM) and a fludarabine+ cyclophosphamide+thiotepa+2Gy TBI conditioning regimen [16 pts and 2 centers performing most (n=13) of the transplants]; (2) a protocol (performed in 2 centers) consisting in the use of G-CSF mobilized peripheral blood stem cells (PBSC) with ex-vivo B and T cell depletion (BT depleted) (15 pts) and a fludarabine+thiotepa+ treosulfan conditioning regimen (14/15 pts). Haplo donors were most frequently the parents [mother (50%), father (29%), brother (14%) and cousin (7%)]. ATG was used in 95% of transplants and the most frequent combination for graft versus host disease (GvHD) prophylaxis was mycophenolate mofetil (MMF)+sirolimus in PTCY and MMF+ cyclosporine A (CSA) in BT depleted. In UD, graft source distribution was 14 BM, 5 PBSC and 5 CB. Conditioning regimens were mainly myeloablative (83%) with fludarabine+thiotepa+ treosulfan in 54% of HSCT. ATG was used in 87% and campath in 9% of transplants; GvHD prophylaxis was CSA and methotrexate in 50%. Neutrophil engraftment at 60 days was 95±4% in Haplo and 84±8% in adult UD, after a median engraftment time of 18 and 22 days, respectively. In Haplo, 7 pts experienced graft failure (3 primary and 4 late), of those 3 had a second allogeneic transplant and were alive at last FU, at 16, 16 and 63 months respectively; 1 patient died after rescue with autologous transplant and 3 were alive after autologous reconstitution. In adult UD, 3 pts had a primary and 1 a late graft failure, none of them had a second transplant and were all alive at last FU, at 2, 13, 28, 118 months respectively. Grade II-IV acute GvHD at 100 days was 25±7% in Haplo and 21±9% in adult UD; acute GvHD grade III-IV was observed in 3 pts in Haplo (none in BT depleted) and 2 pts in adult UD. Chronic GvHD was observed in 10 pts in Haplo (5 extensive, 3 of these in PTCY) and 3 pts in adult UD (2 extensive). OS at 3 years was 88±4%; being 89±5% in Haplo (88±8% for PTCY, 92±8% for BT depleted) and 94±5% in adult UD. 3-year event free survival was 58±7%; in detail, 60±9% in Haplo (56±12% for PTCY, 68±13% for BT depleted) and 60±12% in adult UD. Overall, 8 pts died (5 Haplo and 3 UD) due to infections or GVHD. Among the 5 pts receiving CB transplant 3 are alive (1 of which after graft failure and a second allogeneic transplant). Conclusion: This preliminary analysis shows that, despite an acceptable OS, rejection and chronic GvHD are still of concern; therefore alternative donor transplants for SCD should be performed in experienced centers with prospective clinical trials. Disclosures Pondarré: Blue Bird Bio: Honoraria; Novartis: Honoraria; Addmedica: Membership on an entity's Board of Directors or advisory committees. Zecca:Chimerix: Honoraria. Locatelli:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Miltenyi: Honoraria; Bellicum: Consultancy, Membership on an entity's Board of Directors or advisory committees; bluebird bio: Consultancy. Bader:Medac: Patents & Royalties, Research Funding; Riemser: Research Funding; Neovii: Research Funding; Cellgene: Consultancy; Novartis: Consultancy, Speakers Bureau. Bernaudin:AddMedica: Honoraria; Pierre fabre: Research Funding; BlueBirdBio: Consultancy; Cordons de Vie: Research Funding.

Download Full-text

Allogeneic Hematopoietic Stem Cell Transplantation in Children and Adults with Chronic Granulomatous Disease (CGD): A Study of the Inborn Errors Working Party (IEWP) of the EBMT

Blood ◽

10.1182/blood-2018-99-114841 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 970-970 ◽

Cited By ~ 2

Author(s):

Robert Chiesa ◽

Junfeng Wang ◽

Henric-Jan Blok ◽

Benedicte Neven ◽

Despina Moshous ◽

...

Keyword(s):

Stem Cell ◽

Board Of Directors ◽

Research Funding ◽

Graft Failure ◽

Chronic Gvhd ◽

Conditioning Regimen ◽

Advisory Committees ◽

Hematopoietic Stem ◽

Stem Cell Source ◽

Engraftment Failure

Abstract Introduction: Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disease characterized by impairment of the phagocyte NADPH-oxidase complex, resulting in deficient microbial killing and life-threatening bacterial and fungal infections. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only curative approach, but it can be complicated by graft failure, graft versus-host disease (GvHD) and transplant-related mortality (TRM). In order to define prognostic risk factors in this setting, the IEWP of the EBMT performed a large retrospective registry study on 600 pediatric and adult patients with CGD undergoing allo-HSCT. Patients and Methods: We analyzed the outcome of patients with CGD who received allo-HSCT in EBMT centers between 1993 and 2017. The main end-points of the study were overall survival (OS) and event-free survival (EFS; events were death and primary or secondary engraftment failure) according to patient's age, donor type, stem cell source and conditioning regimen. One patient died before allo-HSCT and was excluded from analysis. Results: We studied 536 children (aged < 18 years) and 63 adults (aged ≥ 18 years) affected by CGD. The median follow-up was 45.37 months (IQR 15.8-81.8). Genetic results were available for 307 patients: inheritance was X-linked (75%) or autosomal recessive (25%). Median age at transplant was 7.2 years (range: 0.12-48.56). Conditioning regimen was Busulfan/Fludarabine (n=244; 41%), Busulfan/Cyclophosphamide (n=104; 17%), Treosulfan/Fludarabine (n=76; 13%), Treosulfan/Fludarabine/Thiotepa (n=52; 9%) or other drug combinations (n=123; 20%). Donors were human leukocyte antigen (HLA) matched related (MFD, 10/10; n=211, 40%), matched unrelated (MUD, 10/10 or 6/6 in UCB; n=201; 38%), mismatched related (MMFD, ≥ 9/10; n= 27; 5%) or mismatched unrelated (MMUD, ≥ 9/10 or 5/6 in UCB; n= 83; 16%). Stem cell source was bone marrow (BM; n=408; 69%), peripheral blood (PB; n=153; 26%) or umbilical cord blood (UCB; n=27; 5%). Donor engraftment occurred in 516 evaluable patients (88%), while primary or secondary engraftment failure occurred in 68 patients (12%). Seventy-nine patients (13%) died after allo-HSCT. The 2 year Kaplan-Meier estimate of OS and EFS were 87.1% (95% CI, 84.2-89.9) and 77.8% (95% CI, 74.2-81.4), respectively (Fig A). The 2-year cumulative incidence of grade II-IV acute GvHD, chronic GvHD and extensive chronic GvHD was 18.6% (95%, 15.1-22.2), 16.2 % (95%, 18.8-19.7) and 5.5% (95%, 3.4-7.7), respectively. A univariate cox model with spline term demonstrated that older age at transplant was associated with an increased risk of death (p=0.002). Children undergoing allo-HSCT had a superior 2y OS (88.1%; 95% CI 85.2-91.0), compared to adults (78.2%; 95% CI, 67.7-88.7), p=0.03 (Fig B). Patients undergoing allo-HSCT from a MFD had a superior EFS (86.5%; 95% CI 81.5-91.4) compared to MUD (73.3%; 95% CI 66.7-79.9), MMUD (78.2%; 95% CI 69-87.5) and MMFD (59.7; 95% CI 40.4-79.1), p< 0.001 (Fig C). Patients receiving BM grafts had superior 2y EFS (81.0%; 95% CI 76.9-85.1) compared to PB (72.5%; 95% CI 64.7-80.4) and UCB (66.7%; 95% CI 48.9-84.4), p=0.04. The pattern of disease inheritance and the choice of conditioning regimen didn't have an impact on outcome (Fig D). Fifty-three patients with graft failure underwent a second allo-HSCT and the 2y OS in this group was 82.1% (95% CI, 71.5-92.7). Year of transplantation didn't have an influence on outcome. Conclusion: This is the largest study describing the outcome of allo-HSCT in children and adults affected by CGD. We demonstrate an excellent outcome, with a low incidence of graft failure, TRM and GvHD. Older patients with CGD have reduced survival after allo-HSCT, indicating that transplant should be considered at a younger age. The use of a MMFD is associated with poorer outcome; indication to transplant in this setting should be carefully evaluated by the treating physicians. Disclosures Chiesa: Bluebird Bio: Consultancy; Gilead: Consultancy. Kalwak:medac: Other: travel grants; Sanofi: Other: travel grants. Sykora:Aventis-Behring: Research Funding; medac: Research Funding. Locatelli:Bellicum: Consultancy, Membership on an entity's Board of Directors or advisory committees; Miltenyi: Honoraria; bluebird bio: Consultancy; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees. Wynn:Orchard SAB: Membership on an entity's Board of Directors or advisory committees; Orchard Therapeutics: Equity Ownership; Chimerix: Research Funding; Genzyme: Honoraria; Bluebird Bio: Consultancy; Orchard Therapeutics: Consultancy; Chimerix: Consultancy. Zecca:Chimerix: Honoraria. Veys:Pfizer: Honoraria; Servier: Research Funding; Novartis: Honoraria. Slatter:Medac: Other: Travel assistance.

Download Full-text

Outcome of Hematopoietic Stem Cell Transplantation in Children with Primary Hemophagocytic Lymphohistiocytosis: A Single Institution Experience Using Reduced Intensity Conditioning

Blood ◽

10.1182/blood-2020-142988 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 43-44

Author(s):

Mohammed Essa ◽

Enas Basher ◽

Rodaina Abujoub ◽

Abdulrahman Alsultan

Keyword(s):

Stem Cell ◽

Graft Failure ◽

Conditioning Regimen ◽

High Rate ◽

Unrelated Donor ◽

Reduced Intensity Conditioning ◽

Hematopoietic Stem ◽

Donor Chimerism ◽

Gvhd Prophylaxis

Hematopoietic stem cell transplantation (HSCT) is the only curative therapy for primary hemophagocytic lymphohistiocytosis (HLH). Conventional myeloablative conditioning regimen using busulfan, cyclophosphamide with or without etoposide was associated with high rate of transplant-related mortality (Horne et al. BJH 2005). Reduced intensity conditioning (RIC) is used in HLH to minimize transplant-related toxicities. The use of alemtuzumab, fludarabine, and melphalan in HLH was associated with low mortality; however, mixed donor chimerism and graft failure were frequent (Allen et al. Blood 2018). A recent report in 25 HLH patients who underwent HSCT from HLA matched donors using targeted busulfan (45-65 mg/L X h), fludarabine, and serotherapy resulted in adequate stable donor chimerism, no graft rejection, and no mortality (Felber et al. Blood Adv. 2020). In this study, we reviewed the outcome of 16 HLH patients who underwent HSCT from HLA matched donors using RIC. All patients were initially treated using HLH-2004 protocol. They subsequently underwent HSCT from 10/10 HLA matched related or unrelated donor using RIC regimens. We initially used AFM conditioning regimen that included alemtuzumab (1 mg/kg), fludarabine (150 mg/m2), and melphalan (140 mg/m2) with or without thiotepa (10 mg/kg). GVHD prophylaxis included cyclosporine (CSA) and steroids. Given the high rate of low donor chimerism with AFM regimen, we subsequently used BF conditioning regimen that included busulfan (weight-based dosing for total of 16 doses) and fludarabine (160 mg/m2). Therapeutic drug monitoring of busulfan was performed. Thymoglobulin (10 mg/kg) was added in matched unrelated donor (MUD). GVHD prophylaxis included CSA and steroids in matched related donors (MRD) and CSA and methotrexate in MUD. Bone marrow was the stem cell source in all patients except one who underwent second transplant using peripheral blood stem cells. Supportive care was consistent among all patients. Defibrotide prophylaxis was administered to prevent sinusoidal obstruction syndrome (SOS). Donor chimerism <5% from whole blood or <20% in T-cell, graft failure, and death from any cause were considered as events. A total of 16 HSCT transplants were performed, 5 received AFM regimen and 11 received BF regimen. Patient and transplant characteristics are shown in Table. All patients had successful neutrophil and platelet engraftments. Among the five patients who underwent AFM conditioning, one patient with SH2D1A mutation is 8 years post transplant with stable full donor chimerism and another patient with PRF1 mutation who received AFM with thiotepa has stable sufficient donor chimerism 3 years post transplant. Both patients did not require donor leukocyte infusions (DLI). The remaining 3 patients had declining donor chimerism beyond the first year of transplant despite the frequent use of DLI, one of them had disease reactivation and underwent second HSCT using BF regimen. Event free survival (EFS) at 3 years was 60% and overall survival (OS) was 100%. Among the 11 patients who underwent BF regimen, 7 were transplanted using MRD and 4 MUD. The median cumulative area under the curve of busulfan was 64 mg/L X h (range, 56-73). Median donor myeloid chimerism was 97% (range, 83-100) and median T-cell chimerism was 78% (range, 40-93). One patient who underwent MUD had grade III acute GVHD and none had chronic GVHD. Two patients had mild SOS. There were no events among BF group with median follow up duration of 393 days (151-2080). The use of BF regimen in HLH was associated with excellent outcome and stable donor chimerism with no graft failure in comparison to AFM regimen. Longer follow up is needed to confirm our findings. Disclosures No relevant conflicts of interest to declare.

Download Full-text

Salvage HLA-haploidentical hematopoietic stem cell transplantation with post-transplant cyclophosphamide for graft failure in non-malignant disorders

Bone Marrow Transplantation ◽

10.1038/s41409-021-01323-9 ◽

2021 ◽

Author(s):

Michael H. Albert ◽

Mehtap Sirin ◽

Manfred Hoenig ◽

Fabian Hauck ◽

Catharina Schuetz ◽

...

Keyword(s):

T Cell ◽

Graft Failure ◽

Acute Gvhd ◽

Chronic Gvhd ◽

Conditioning Regimen ◽

Reduced Intensity Conditioning ◽

Post Transplantation ◽

Hematopoietic Stem ◽

Reduced Intensity

AbstractGraft failure requires urgent salvage HSCT, but there is no universally accepted approach for this situation. We investigated T-cell replete haploidentical HSCT with post-transplantation cyclophosphamide following serotherapy-based, radiation-free, reduced intensity conditioning in children with non-malignant disorders who had rejected their primary graft. Twelve patients with primary or secondary graft failure received T-cell replete bone marrow grafts from haploidentical donors and post-transplantation cyclophosphamide. The recommended conditioning regimen comprised rituximab 375 mg/m2, alemtuzumab 0.4 mg/kg, fludarabine 150 mg/m2, treosulfan 20–24 g/m2 and cyclophosphamide 29 mg/kg. After a median follow-up of 26 months (7–95), eleven of twelve patients (92%) are alive and well with complete donor chimerism in ten. Neutrophil and platelet engraftment were observed in all patients after a median of 18 days (15–61) and 39 days (15–191), respectively. Acute GVHD grade I was observed in 1/12 patients (8%) and mild chronic GVHD in 1/12 patients (8%). Viral reactivations and disease were frequent complications at 75% and 42%, respectively, but no death from infectious causes occurred. In summary, this retrospective analysis demonstrates that a post-transplantation cyclophosphamide-based HLA-haploidentical salvage HSCT after irradiation-free conditioning results in excellent engraftment and overall survival in children with non-malignant diseases.

Download Full-text

Transplantation for Congenital Sideroblastic Anaemia Is Feasible and Offers Outcomes Comparable to Other Transfusion Dependent Anaemias. a Joint Retrospective Study of the Paediatric Diseases and Severe Aplastic Anaemia Working Parties (PDWP/SAAWP) of EBMT

Blood ◽

10.1182/blood-2020-142397 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 45-47

Author(s):

Josu de la Fuente ◽

Dirk-Jan Eikema ◽

Paul Bosman ◽

Robert F Wynn ◽

Miguel Díaz ◽

...

Keyword(s):

Bone Marrow ◽

Board Of Directors ◽

Research Funding ◽

Graft Failure ◽

Chronic Gvhd ◽

Conditioning Regimen ◽

Response To Treatment ◽

Variable Response ◽

Advisory Committees ◽

Grade Ii

Congenital sideroblastic anaemias (CSA) are a rare group of disorders characterized by the presence of pathologic iron deposits within the mitochondria of erythroid precursors (ring sideroblasts) in the bone marrow due to heterogenous germline mutations leading to defects in mitochondrial heme synthesis, iron-sulfur (Fe-S) cluster biogenesis, or protein synthesis. Patients present with anaemia and relative reticulocytopenia, and systemic iron overload secondary to chronic ineffective erythropoiesis, leading to end-organ damage. The disease is heterogenous underlying the genetic variability and the variable response to treatment. Although a number of CSA patients have received a bone marrow transplant, the outcomes and toxicities are not known. This status makes it very difficult to understand the role of BMT in the management of CSA. A search in the EBMT database identified 28 patients receiving a HSCT for CSA between 1998 to 2018 by 24 participating centres. The median year of transplantation was 2014 (IQR 2004-2016). The distribution was equal between males (n=14) and females (n=14). The median age at transplantation was 7 years of age (3-10 years). Fifteen patients had a sibling HSCT (88%), one a family matched donor HSCT (6%) and one an unrelated matched (6%), the type of transplant being unknown in others (n=11). The source of stem cells was bone marrow in 20 cases (74%), peripheral blood in 4 cases (15%), cord blood in 2 (7%) and combined bone marrow and cord in one (4%). Five cases had a Bu/Cy based conditioning regimen, 4 had Bu/fludarabine based regimen and three fludarabine/treosulfan based conditioning with the rest having a variety of approaches. Eighty-six percent of cases had serotherapy with ATG or alemtuzumab. The median follow-up was 31.6 months (95% CI, 12.2-74.1%). The overall survival at 12 and 24 months was 88% (76-100) and 82% (66-99), respectively (figure 1). The median neutrophil engraftment was 18 (15-21) days and platelet engraftment >20 x 109/L was 29 (20-51) days, with a graft failure incidence of 7% (0-17) at 12 months. Two patients suffered from VOD. There were four deaths, three of which were related to transplant complications. The event free survival (survival without graft failure, relapse and second transplant) at 12 and 24 months was 85% (72-99) (figure 2). Six patients developed acute GvHD grade II and one case grade III; giving a grade II/III incidence of 28% (10-46). There was one case of limited and one of chronic GvHD, giving an incidence of 11% (0-26%) at 12 months and 24 months. In conclusion, whilst HSCT for CSA is a rare occurrence, these data demonstrate that HSCT for this condition is feasible and the outcomes are in keeping with those obtained for transplantation for transfusion dependent anaemias during the same time-period. Disclosures Handgretinger: Amgen: Honoraria. Moraleda:Gilead: Consultancy, Other: Travel Expenses; Jazz Pharmaceuticals: Consultancy, Research Funding; Novartis: Consultancy, Other: Travel Expenses; Sandoz: Consultancy, Other: Travel Expenses; Takeda: Consultancy, Other: Travel Expenses. Risitano:Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Alnylam: Research Funding; Alexion: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Jazz: Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees; Samsung: Membership on an entity's Board of Directors or advisory committees; Amyndas: Consultancy; RA pharma: Research Funding; Biocryst: Membership on an entity's Board of Directors or advisory committees; Apellis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Achillion: Membership on an entity's Board of Directors or advisory committees; Pfizer: Speakers Bureau. Peffault De Latour:Amgen: Research Funding; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Apellis: Membership on an entity's Board of Directors or advisory committees; Alexion Pharmaceuticals Inc.: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Download Full-text

Lower Hematopoietic Progenitor Cell Counts and Yields at Subsequent Donations Is Influenced By a Shorter Inter-Donation Interval between the First and Subsequent Mobilizations

Blood ◽

10.1182/blood-2019-123492 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 1962-1962

Author(s):

Sandhya R. Panch ◽

Brent R. Logan ◽

Jennifer A. Sees ◽

Bipin N. Savani ◽

Nirali N. Shah ◽

...

Keyword(s):

Stem Cell ◽

Board Of Directors ◽

Peripheral Blood ◽

Research Funding ◽

Time Interval ◽

Advisory Committees ◽

Hematopoietic Stem ◽

Peripheral Blood Cd34 ◽

Cell Counts ◽

Cd34 Cells

Introduction: Approximately 7% of unrelated hematopoietic stem cell (HSC) donors are asked to donate a subsequent time to the same or different recipient. In a recent large CIBMTR study of second time donors, Stroncek et al. incidentally found that second peripheral blood stem cell (PBSC) collections had lower total CD34+ cells, CD34+ cells per liter of whole blood processed, and CD34+ cells per kg donor weight. Based on smaller studies, the time between the two independent PBSC donations (inter-donation interval) as well as donor sex, race and baseline lymphocyte counts appear to influence CD34+ cell yields at subsequent donations. Our objective was to retrospectively evaluate factors contributory to CD34+ cell yields at subsequent PBSC donation amongst NMDP donors. Methods. The study population consisted of filgrastim (G-CSF) mobilized PBSC donors through the NMDP/CIBMTR between 2006 and 2017, with a subsequent donation of the same product. evaluated the impact of inter-donation interval, donor demographics (age, BMI, race, sex, G-CSF dose, year of procedure, need for central line) and changes in complete blood counts (CBC), on the CD34+ cell yields/liter (x106/L) of blood processed at second donation and pre-apheresis (Day 5) peripheral blood CD34+ cell counts/liter (x106/L) at second donation. Linear regression was used to model log cell yields as a function of donor and collection related variables, time between donations, and changes in baseline values from first to second donation. Stepwise model building, along with interactions among significant variables were assessed. The Pearson chi-square test or the Kruskal-Wallis test compared discrete variables or continuous variables, respectively. For multivariate analysis, a significance level of 0.01 was used due to the large number of variables considered. Results: Among 513 PBSC donors who subsequently donated a second PBSC product, clinically relevant decreases in values at the second donation were observed in pre-apheresis CD34+ cells (73.9 vs. 68.6; p=0.03), CD34+cells/L blood processed (32.2 vs. 30.1; p=0.06), and total final CD34+ cell count (x106) (608 vs. 556; p=0.02). Median time interval between first and second PBSC donations was 11.7 months (range: 0.3-128.1). Using the median pre-apheresis peripheral blood CD34+ cell counts from donation 1 as the cut-off for high versus low mobilizers, we found that individuals who were likely to be high or low mobilizers at first donation were also likely to be high or low mobilizers at second donation, respectively (Table 1). This was independent of the inter-donation interval. In multivariate analyses, those with an inter-donation interval of >12 months, demonstrated higher CD34+cells/L blood processed compared to donors donating within a year (mean ratio 1.15, p<0.0001). Change in donor BMI was also a predictor for PBSC yields. If donor BMI decreased at second donation, so did the CD34+cells/L blood processed (0.74, p <0.0001). An average G-CSF dose above 960mcg was also associated with an increase in CD34+cells/L blood processed compared to donors who received less than 960mcg (1.04, p=0.005). (Table 2A). Pre-apheresis peripheral blood CD34+ cells on Day 5 of second donation were also affected by the inter-donation interval, with higher cell counts associated with a longer time interval (>12 months) between donations (1.23, p<0.0001). Further, independent of the inter-donation interval, GCSF doses greater than 960mcg per day associated with higher pre-apheresis CD34+ cells at second donation (1.26, p<0.0001); as was a higher baseline WBC count (>6.9) (1.3, p<0.0001) (Table 2B). Conclusions: In this large retrospective study of second time unrelated PBSC donors, a longer inter-donation interval was confirmed to be associated with better PBSC mobilization and collection. Given hematopoietic stem cell cycling times of 9-12 months in humans, where possible, repeat donors may be chosen based on these intervals to optimize PBSC yields. Changes in BMI are also to be considered while recruiting repeat donors. Some of these parameters may be improved marginally by increasing G-CSF dose within permissible limits. In most instances, however, sub-optimal mobilizers at first donation appear to donate suboptimal numbers of HSC at their subsequent donation. Disclosures Pulsipher: CSL Behring: Membership on an entity's Board of Directors or advisory committees; Miltenyi: Research Funding; Bellicum: Consultancy; Amgen: Other: Lecture; Jazz: Other: Education for employees; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Medac: Honoraria. Shaw:Therakos: Other: Speaker Engagement.

Download Full-text

Inducible SBDS Deficiency Impairs Bone Marrow Niche Function to Engraft Donor Hematopoietic Stem Cell after Transplantation

Blood ◽

10.1182/blood-2019-121763 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 3199-3199

Author(s):

Ji Zha ◽

Lori Kunselman ◽

Hongbo Michael Xie ◽

Brian Ennis ◽

Jian-Meng Fan ◽

...

Keyword(s):

Bone Marrow ◽

Stem Cell ◽

Mouse Model ◽

Board Of Directors ◽

Hematopoietic Stem Cell ◽

Graft Failure ◽

Advisory Committees ◽

Hematopoietic Stem ◽

Bm Niche ◽

Deficient Mice

Hematopoietic stem cell (HSC) transplantation (HSCT) is required for curative therapy for patients with high-risk hematologic malignancies, and a number of non-malignant disorders including inherited bone marrow failure syndromes (iBMFS). Strategies to enhance bone marrow (BM) niche capacity to engraft donor HSC have the potential to improve HSCT outcome by decreasing graft failure rates and enabling reduction in conditioning intensity and regimen-associated complications. Several studies in animal models of iBMFS have demonstrated that BM niche dysfunction contributes to both the pathogenesis of iBMFS, as well as impaired graft function after HSCT. We hypothesize that such iBMFS mouse models are useful tools for discovering targetable niche elements critical for donor engraftment after HSCT. Here, we report the development of a novel mouse model of Shwachman-Diamond Syndrome (SDS) driven by conditional Sbds deletion, which demonstrates profound impairment of healthy donor hematopoietic engraftment after HSCT due to pathway-specific dysfunctional signaling within SBDS-deficient recipient niches. We first attempted to delete Sbds specifically in mature osteoblasts by crossing Sbdsfl/flmice with Col1a1Cre+mice. However, the Col1a1CreSbdsExc progenies are embryonic lethal at E12-E15 stage due to developmental musculoskeletal abnormalities. Alternatively, we generated an inducible SDS mouse model by crossing Sbdsfl/flmice with Mx1Cre+ mice, and inducing Sbds deletion in Mx1-inducible BM hematopoietic and osteolineage niche cells by polyinosinic-polycytidilic acid (pIpC) administration. Compared with Sbdsfl/flcontrols, Mx1CreSbdsExc mice develop significantly decreased platelet counts, an inverted peripheral blood myeloid/lymphoid cell ratio, and reduced long-term HSC within BM, consistent with stress hematopoiesis seen in BMF and myelodysplastic syndromes. To assess whether inducible SBDS deficiency impacts niche function to engraft donor HSC, we transplanted GFP+ wildtype donor BM into pIpC-treated Mx1CreSbdsExc mice and Sbdsfl/flcontrols after 1100 cGy of total body irradiation (TBI). Following transplantation, Mx1CreSbdsExc recipient mice exhibit significantly higher mortality than controls (Figure 1). The decreased survival was related to primary graft failure, as Mx1CreSbdsExc mice exhibit persistent BM aplasia after HSCT and decreased GFP+ reconstitution in competitive secondary transplantation assays. We next sought to identify the molecular and cellular defects within BM niche cells that contribute to the engraftment deficits in SBDS-deficient mice. We performed RNA-seq analysis on the BM stromal cells from irradiated Mx1CreSbdsExc mice versus controls, and the results revealed that SBDS deficiency in BM niche cells caused disrupted gene expression within osteoclast differentiation, FcγR-mediated phagocytosis, and VEGF signaling pathways. Multiplex ELISA assays showed that the BM niche of irradiated Mx1CreSbdsExc mice expresses lower levels of CXCL12, P-selectin and IGF-1, along with higher levels of G-CSF, CCL3, osteopontin and CCL9 than controls. Together, these results suggest that poor donor HSC engraftment in SBDS-deficient mice is likely caused by alterations in niche-mediated donor HSC homing/retention, bone metabolism, host monocyte survival, signaling within IGF-1 and VEGF pathways, and an increased inflammatory state within BM niches. Moreover, flow cytometry analysis showed that compared to controls, the BM niche of irradiated Mx1CreSbdsExc mice contained far fewer megakaryocytes, a hematopoietic cell component of BM niches that we previously demonstrated to be critical in promoting osteoblastic niche expansion and donor HSC engraftment. Taken together, our data demonstrated that SBDS deficiency in BM niches results in reduced capacity to engraft donor HSC. We have identified multiple molecular and cellular defects in the SBDS-deficient niche contributing to this phenotype. Such niche signaling pathway-specific deficits implicate these pathways as critical for donor engraftment during HSCT, and suggest their potential role as targets of therapeutic approaches to enhance donor engraftment and improve HSCT outcome in any condition for which HSCT is required for cure. Disclosures Olson: Merck: Membership on an entity's Board of Directors or advisory committees; Bluebird Bio: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Miltenyi: Honoraria.

Download Full-text

Potential Increase in Graft Failure Risk after Reduced Intensity Conditioning Stem Cell Transplant (RIT) Using Umbilical Cord Blood for Children with Primary Immunodeficiency.

Blood ◽

10.1182/blood.v110.11.2006.2006 ◽

2007 ◽

Vol 110 (11) ◽

pp. 2006-2006

Author(s):

Jessica Guarino ◽

Morris Kletzel ◽

Reggie Duerst ◽

David Jacobsohn ◽

Jennifer Schneiderman ◽

...

Keyword(s):

Stem Cell ◽

Cord Blood ◽

Median Time ◽

Primary Immunodeficiency ◽

Graft Failure ◽

Conditioning Regimen ◽

Reduced Intensity Conditioning ◽

Cd34 Cells ◽

Unrelated Donors ◽

Reduced Intensity

Abstract Allogeneic stem cell transplantation is curative for patients with primary immunodeficiency. A unique reduced intensity conditioning regimen has been developed to maximize cure rate and minimize transplant-related toxicity. Between 2000 and 2007, we performed 16 RIT in patients with hyper-IgM syndrome (n=2), severe combined immune deficiency (SCID) (n=10), immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome (IPEX) (n=2), Wiskott-Aldrich syndrome (n=1), and X-linked lymphoproliferative disease (n=1). There were 12 males and 4 females, with a median age at the time of RIT of 8.0 months (range 1.1 months to 8.9 years). Donor sources included peripheral blood stem cells (PBSCs) from matched related donors (n=7) or unrelated donors (n=2), and cord blood units (CBUs) (n=7). The median cell dose was 8.55 × 108 total nucleated cells (TNC)/kg and 6.7 × 106 CD34+cells/kg for the PBSC group, and 1.99 × 108 TNC/kg and 0.71 × 106 CD34+cells/kg for the CBU group. The conditioning regimen consisted of Fludarabine (Flu), days -10 through -5, intravenous Busulfan (Bu), days -5 and -4, and Anti-thymocyte globulin (ATG), days -4 through -1. GVHD prophylaxis included tacrolimus/prednisone (n=1), cyclosporine A (CSA) alone (n=2), and CSA/mycophenolate mofetil (n=13). All patients who received PBSCs from related and unrelated donors engrafted (9/9), whereas only 4/7 (57%) patients who received CBUs engrafted. The 3 patients who experienced primary graft failure had the following diagnoses; IPEX, T−B−NK+ SCID and T−B+NK+ SCID. Their cord blood doses were 0.78, 1.19 and 1.99 × 108 TNC/kg, and 0.11, 0.69, and 0.55 × 106 CD34+cells/kg, respectively. For the 13 patients who engrafted, median time to absolute neutrophil count (ANC) >1000 was 19 days (range 4 to 53) and median time to platelets >50K was 23 days (range 14 to 90). The ANC never dropped <500 for 8/13 (62%) patients, and platelets never dropped <20K for 9/13 (69%) patients who engrafted. VNTR analysis of donor cell contribution showed that full donor chimerism was achieved in 8/16 patients (50%; 6 received PBSCs and 2 received CBUs), and, partial donor chimerism was achieved in 5/16 patients (31%; 3 received PBSCs and 2 received CBUs). Toxicities within 100 days post-RIT included bacteremia (n=8), candidemia (n=1), and viral infection (n=6). All infections were effectively treated and patients fully recovered. No episodes of seizure or veno-occlusive disease were experienced. No mucositis or severe nausea/vomiting was reported. No grade III/IV acute graft-versus-host disease (GVHD) or chronic GVHD was seen. Three patients died within 100 days post-RIT from causes related to primary or secondary graft failure. The overall survival was 81.0% at 2 year post-RIT (95% CI 89.5–71.5). All deceased patients received CBUs as the donor source. One of these patients were considered high-risk with pre-RIT Lansky score =30%. If this patient was excluded from analysis, the 100 day RIT related mortality was 13.3%. This retrospective analysis revealed that RIT with Flu/Bu/ATG conditioning is well tolerated in children with primary immunodeficiency. The use of CBUs, however, appeared to increase the risk of graft failure. A larger study of the use of RIT in primary immunodeficiency could further examine this hypothesis.

Download Full-text