Related Peripheral Blood Stem Cell Research Articles

Psychological and physical side effects during G-CSF mobilization in related donors of allo-HCT.

The psychological side effects of granulocyte colony-stimulating factor mobilization in related donors of allogeneic hematopoietic cell transplantation (allo-HCT) and impacts of psychological/physical side effects on harvest outcomes remain largely unknown. We prospectively analyzed 349 consecutive related peripheral blood stem cell (PBSC) donors for allo-HCT at the First Affiliated Hospital, Zhejiang University, School of Medicine from March 2021 to August 2023. Higher baseline peripheral blood white blood cell counts (p = 0.046), monocyte counts (p < 0.001), platelet counts (p = 0.001), and hemoglobin (p < 0.001) had a positive correlation to CD34+ cell counts in the first leukapheresis, while female donors (male vs. female, p < 0.001) and older age (> 40 vs. < = 40, p = 0.003) were negatively related to CD34+ cell counts. Bone pain was the most observed physical side effect and was more frequent in female donors (p = 0.032). The incidence of fatigue was higher in female donors and older donors (female vs. male, p = 0.016; > 40 vs. < = 40, p = 0.015). Donor depression (pre vs. during mobilization, p < 0.001), anxiety (pre vs. during mobilization, p = 0.043) and insomnia (pre vs. during mobilization, p = 0.011) scores increased during the mobilization period. Donors with higher depression, anxiety and stress scores at admission were more likely to experience nausea. At 1 month after the last leukapheresis, the counts of white blood cell, neutrophil, monocyte and hemoglobin were significant lower than baseline counts, while the platelet counts recovered to baseline. The mobilization and harvest process can increase the depression, anxiety and insomnia scores. Poor psychological status of the donor can aggravate the occurrence of physical side effects.

Outcome and late effects of matched related peripheral-blood stem-cell transplantation in children with severe aplastic anemia

Background Aplastic Anemia (AA) is a life- threatening disease. Cure can be achieved in a large proportion of patients with prompt treatment with matched sibling donor Hematopoietic Stem Cell Transplantation (HSCT) as first line therapy. Aim Study of the outcomes and late effects among children with severe aplastic anemia after receiving matched related peripheral-blood stem-cell (PBSC) transplantation and cyclophosphamide/antithymocyte globulin conditioning regimen at Ain Shams University Pediatric Bone Marrow Transplantation Unit, Cairo, Egypt. Methods Data of 15 patients with severe aplastic anemia who received matched related PBSC transplantation between January 2011 and December 2018 were analysed retrospectively. All long-term survivors were followed up for 2 years. Follow up studies included detailed assessment of growth, graft evaluation, immune reconstitution, long-term effects on the liver, kidney, pulmonary, cardiac, endocrine functions, chronic graft-versus-host disease (GVHD), and infectious complications. Results The median duration of the study was 87 months (43–115 months). The overall survival was 73.3%. Event-free survival was 66.7%. All mortality was within 2 months posttransplant. Blood counts were within normal limits. Chimerism was complete for all except one. Growth assessment revealed Z score of weight, height, and BMI 0 (−1.8–1.6), −0.7 (−1.8–0.95), and 0.34 (−1.29–2). Abnormal thyroid function was found in three (27%) patients. No documented high-grade acute GVHD or extensive chronic GVHD. Cardiac, pulmonary, hepatic, and renal functions showed no abnormality. Immune reconstitution was consistent, and no malignant complications were reported. Conclusion This study confirmed the feasibility and safety of matched related PBSC transplantation in the pediatric population in low-income countries. Overall survival and event-free survival were satisfactory.

Efficacy of Triple Prophylaxis for Prevention of Graft-Versus-Host Disease in Matched Sibling Allogeneic Peripheral Blood Hematopoietic Stem Cell Transplantation in Pediatric Patients

BACKGROUND: Graft-versus-host disease (GVHD) continues to compromise the overall success of allogenic hematopoietic stem cell transplantation. It is the most important cause of morbidity and non-relapse mortality after allogeneic hematopoietic stem cell transplantation for malignant disease. In adults, post-transplant cyclophosphamide (Cy-PT) has been shown to be a feasible, economically accessible, and effective strategy to reduce the incidence of GVHD in matched sibling hematopoietic stem cell transplantation in combination with a calcineurin inhibitor plus mycophenolate mofetil (MMF). AIM: Demonstrate the clinical benefit of Cy-PT plus a calcineurin inhibitor combined with MMF for GVHD prophylaxis in HLA-matched, related peripheral blood stem cell transplants in pediatric patients with malignant hematologic neoplasms compared to standard therapy in historical controls. METHODS: A retrospective study was conducted on 22 pediatric patients with malignant hematologic neoplasms who underwent HLA-matched related peripheral blood allogenic stem cell transplantation (alloSCT) between July 2012 and December 2022. A comparison was made between two groups, one with triple prophylaxis using Cy-PT, cyclosporine (CsA), and MMF, and a historical cohort that received standard GVHD prophylaxis based on CsA and methotrexate (MTX). Patients were identified from a hospital registry. Descriptive and inferential statistics will be reported, using SPSS version 25 for analysis. RESULTS: Twenty-two patients received HLA-matched alloSCT from first-degree relatives genotypically identical in HLA-A, HLA-B, and HLA-DRB1 alleles. The demographic characteristics of both groups are summarized in the table. No patient experienced primary graft failure, sinusoidal obstructive syndrome, or hemorrhagic cystitis. Acute GVHD grade II-IV did not develop in patients who received Cy-PT, whereas in the CsA/MTX prophylaxis group, 1 (9%) grade IV patient was observed who died due to this cause before day 100. Two patients (18%) developed Moderate/Severe GVHD in the CsA/MTX group, and 1 (9%) had moderate GVHD in the Cy-PT group. Two-year overall survival was similar between the two groups (Cy-PT 53% and CsA/MTX 67%), as was event-free survival (PTCy 48% vs. CsA/MTX 61%). CONCLUSION: Peripheral blood represents a feasible option in our setting due to rapid graft engraftment, short hospital stays, and low incidence of primary graft failure, but with a higher incidence of GVHD as reported in the literature. We explored the efficacy and safety of triple prophylaxis for HLA-matched alloSCTs from peripheral blood using Cy-PT + CsA + MMF in a small group of patients, with outcomes slightly better than standard prophylaxis. These preliminary results motivate us to continue with this new regimen.

Retrospective Study of Allogeneic Hematopoietic Stem Cell Transplantation for Relapse or Refractory Peripheral T-Cell Lymphoma at Toranomon Hospital and Toranomon Hospital Kajigaya

[Background] Relapsed or refractory peripheral T-cell lymphoma (R/R PTCL) is known to have a poor prognosis. Although new medications have been introduced in recent years, allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only curative treatment for R/R PTCL. We review the results of allo-HSCT for PTCL at our institution. [Methods] We performed a retrospective analysis of R/R PTCL patients who underwent first allo-HSCT at our hospital from February 2011 and April 2023. The primary endpoint was OS, which was defined as the time from allo-HSCT to death from any cause or the last follow-up. The secondary endpoints included progression-free survival (PFS), relapse/progression incidence (RI) and non- relapse mortality (NRM). PFS was defined as the time from allo-HSCT to relapse/progression, death, or the last follow-up. OS and PFS were estimated by the Kaplan-Meier method and multivariate Cox proportional hazard models. The cumulative incidence of relapse and NRM were investigated with a competing risk analysis using Gray's test and multivariable Fine and Gray competing risk regression. [Results] During the study period, a total of 44 patients received first allo-HSCT for PTCL (ALK positive ALCL: 2, ALK negative ALCL: 2, AITL: 10, PTCL-NOS: 21, CTCL: 7, HSTL: 2). The median follow-up months of survivors was 51.6 (range, 2.6-141.6). The median age of patients at transplantation was 50 years (range, 17-70). Clinical stage I/II at diagnosis was 10 cases, and clinical stage III/IV was 34 cases. Prognostic Index for PTCL(PIT) was score 1 in 20 cases, score 2 in 20 cases and score 3 in 3 cases. Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) ≧ 2 was 21 cases. Performance Status (PS) 0-1 was 32 cases and PS 2-4 was 12 cases. Primary induction failure (PIF) was 28 cases and relapse after first remission (REL) was 16 cases, including 5 cases of relapse after autologous stem cell transplantation. Median number of chemotherapy regimens received before allo-HSCT was 3 (range, 1-8). Clinical stage at transplantation was CR/PR in 23 patients and SD/PD in 21 patients.The majority, thirty-two had received unrelated cord blood transplantation (CBT), six did unrelated bone marrow transplantation (uBMT), and 6 did related peripheral blood stem cell transplantation (rPBSCT). Thirty-two patients received myeloablative conditioning (MAC), eighteen of which included total body irradiation (TBI) and 15 of which included busulfan (BU). Twelve patients received reduced-intensity conditioning (RIC) . Regarding the primary endpoint, the 4-year OS after allo-HSCT was 53.3%. The 4-year PFS, RI and NRM were 50.4%, 20.7% and 28.8%, respectively. The 4-year OS of CBT, uBMT and rPBSCT patients was 55.2%, 66.7% and 33.3%, respectively. The 4-year OS of REL and PIF patients was 79.1% and 39.5%, respectively (p&amp;lt;0.01). The 4-year OS of MAC and RIC was 49.5% and 64.3%, respectively (p=0.58). The 4-year OS of patients with TBI was superior to patients without TBI (71.1% vs 40.3%, p=0.05). The 4-year OS of CR/PR patients at transplant was superior to SD/PD patients (67.1% vs. 42.9%, p=0.05). In the univariate analysis, PS 0-1, HCT-CI 0-1, REL, CR/PR patients at transplant, patients with TBI and patients without BU were favorable prognostic factors. In the multivariable analysis, REL was associated with better OS (p=0.01, HR 0.16; 95% CI: 0.04-0.65). Except for 3 patients who died from transplant complications before engraftment, 41 patients achieved neutrophil engraftment, with a median engraftment date of 19 days (range, 11-31 days) after transplantation. Twenty-seven patients had acute GVHD (Grade I: 3, Grade II: 13, Grade III: 8, Grade IV: 3), and 11 patients had chronic GVHD. Eleven patients relapsed after transplant, and the median time from transplant to relapse was 26.3 months (range, 0.6-87.1 months). Three patients survived at the last follow up, and the median follow-up time of survivors from relapse was 430 days (range, 12-1301). [Conclusion] Our data indicated good results of allo-HSCT for R/R PTCL, and significantly better in relapse after first remission patients.

Excellent Outcome Following Sibling Peripheral Blood Hematopoietic Stem Cell Transplantation for Glanzmann Thrombasthenia: A Case Report

Glanzmann thrombasthenia (GT) is a rare autosomal recessive platelet disorder due to a qualitative or quantitative anomaly of the platelet membrane glycoprotein GPIIb/IIIa. Its clinical manifestations include mild to severe bleeding. GT diagnosis mainly depends on platelet function analysis, flow cytometry, and gene detection. Treatment methods include conservative symptomatic treatment and allogeneic hematopoietic stem cell transplantation (allo-HSCT). Allo-HSCT is the only clinical radical method for GT. Herein, we report a 2-year-old boy with GT successfully cured by related identical peripheral blood stem cell transplantation (PBSCT). The platelet disorder was corrected to a normal level after PBSCT, with no significant complication related to the transplantation. Hematopoietic stem cell transplantation with full-matched donor in early stage could be a treatment option for GT.

Intravenous Once-Daily BuCy 2 With Pharmacokinetic (PK)-Guided Dose Adjustment As Conditioning Regimen For AML Patients In First Complete Remission

Introduction Busulfan (Bu) represents a backbone as conditioning prior to hematopoietic stem cell transplantation (HSCT). The intravenous (IV) form of Busulfan allows 100% bioavaibility and a limited inter- and intra-patient (pt) variability compared to the oral form. In Europe, IV Bu (Busilvex® fixed dose of 0.8 mg/kg x 16 doses) in combination with Cyclophosphamide (60 mg/kg/d x 2) is indicated prior to conventional HSCT in adults when the combination is the best available option. IV BuCy2 allows a precise delivery with 80% of adult pts within the defined therapeutic window [900 μmol/L x min-100 μmol/L x min] without dose-adjustments. Despite major advances in the risk-stratification and management of acute myelogenous leukaemia (AML) based on cytogenetics and molecular biology, the relapse rate remains high. Several published experiences suggested that Bu exposure may have an impact on the clinical outcomes after allogeneic HSCT. Study Objective The study was implemented to explore the use of a narrow range and high values of Bu exposure [4400 µmol/Lx min to 6000 µmol/Lx min] with a PK-guided dose adjustments and once-daily administration x 4 days. Methods The study was a prospective non-randomized multicentric phase II. The eligible pts were required to have AML in first complete (CR1, cytological remission) and to be eligible allogeneic HSCT following a myeloablative regimen. On the first day of the conditioning regimen IV Bu was administered as a single dose of 3.2 mg/kg; further daily dose of IV Bu were determined based on the previous Bu AUC exposure. The graft-versus-host disease (GVHD) prophylaxis consisted of calcineurin inhibitor, IV methotrexate post-transplant. The addition of antithymoglobulin (ATG) for unrelated donors was decided by each center based on their institutional guidelines. Pts could either receive related or unrelated bone marrow or peripheral blood stem cells. Nine centres with laboratory facilities for the pharmacokinetics analysis entered the study. Patient and transplant characteristics Thirty AML pts in CR1 (21 males, 70%) were treated between may 2010 and may 2012, 87% of pts had de novo AML. Twenty pts (67%) had matched sibling donor, the remaining pts received allograft from an unrelated donor. The median age of the cohort was 43.5 years [19.3-55.5]. The performance status score was comprised between 90 and 100. The majority of the cohort (83%) had an intermediate or unfavorable cytogenetic risk-factors. In 3 cases (10%) the karyotyping analyses could not be performed; 1 pt (3%) did not have cytogenetic test performed. Results Thirty pts were treated and analyzed. The expected cumulative AUC over 4 days [17600 µmol/Lxmin -24000 µmol/Lxmin] was reached in 90% of pts. The mean dose of IV Bu administered was 3.51 mg/kg/day. The mean total cumulative dose of IV Bu over 4 days was 13.25 mg/kg [8-21.3]. All pts engrafted. For the entire cohort, the neutrophil engraftment [absolute neutrophil count (ANC) > 0.5 x 10 9/L] occured at a median time of 17.5 d (11-35). Overall, 3 episodes (10%) of sinusoidal obstruction syndrome (S.O.S) occured (one mild, two severe, all resolved) in two patients. One pt developed 2 severe episodes of S.O.S and received defibrotide. Overall, 12 pts out of 30 (40%) developed acute GVHD between day 0 and day +100 after transplant (4 pts had grade III, 6 pts had grade II and 2 pts developed grade III, no patient developed grade IV). The median follow-up was 12 months [95% CI (11.9-12.2)] After day +100, 4 pts died of non-relapse causes ; one death from pulmonary fibrosis was related to the conditioning regimen. The cumulative incidence of TRM was 13.3% [95% CI (11.1%-15.6%)]. Five pts relapsed at a median time of 3.3 months [2-5.6] and 4 pts died of relapse. The cumulative incidence of one-year survival was 73.3% [95% CI (53.7%-85.7%)]. Conclusion The AUC intensification with once-daily IV BuCy2 is effective and yields an acceptable one year TRM for pts with high-risk AML in CR1. However, longer follow-up is needed in order to assess the impact of AUC intensification on the relapse rate and survivals. Disclosures: Suarez:Laboratoires Pierre Fabre: Travel grant Other. Off Label Use: IV Busulfan was administered in once-daily in this study. In Europe, IV Busulfan combined to cyclophosphamide is registered with a different schedule (infusion of IV Busulfan four times a day). IV Busulfan (Busilvex(r)) is an alkylating agent used as a conditioning regimen prior to hematopoietic stem cell transplantation. Socie:Laboratoires Pierre Fabre: Speakers Bureau. Michallet:Genzyme, MSD, BMS, Novartis, TEVA, Pfizer: Honoraria, Membership on an entity’s Board of Directors or advisory committees. Paci:Laboratoires Pierre Fabre: Honoraria. Blaise:Laboratoires Pierre Fabre: Speakers Bureau, travel grant Other. Marcais:Laboratoires Pierre Fabre: travel grant Other. Xhaard:Laboratoires Pierre Fabre: Honoraria. Nicolini:BMS, Teva, Ariad, Pfizer, Novartis: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau. Furst:Laboratoires Pierre Fabre: travel grant Other. Levrault:Laboratoires Pierre Fabre: Employment. Riggi:Laboratoires Pierre Fabre: Employment. Ta Thanh Minh:Laboratoires Pierre Fabre: Employment.

Stable Engraftment with Haploidentical Peripheral Blood Stem Cell Transplantation in Adult Patients with Sickle Cell Disease

The widespread application of allogeneic hematopoietic stem cell transplantation (HSCT) to cure patients with clinically aggressive sickle cell disease (SCD) has been limited by a lack of HLA-matched sibling donors. HSCT from a haploidentical donor represents a feasible option to increase transplant availability to a majority of the patients. However, current published studies using haploidentical donors in adults with SCD have resulted in long-term event-free survival rates of only 50-57%.Here we describe 10 consecutive haploidentical HSCT (haplo-HSCT) performed in adult patients with clinically aggressive SCD lacking an HLA-matched sibling donor. The median age of recipients was 27 years (range, 20-52 years) and all 10 patients met at least two standard SCD eligibility criteria for HSCT (Table 1). Based on our successful experience in matched related peripheral blood stem cell (PBSC) HSCT using a nonmyeloablative conditioning regimen with alemtuzumab 1mg/kg and 3 Gy total body irradiation (TBI), we initially performed two haplo-HSCT using the same conditioning regimen followed by high dose post-transplant cyclophosphamide (PT-Cy) at 50mg/kg on day+3 and +4. Both SCD patients failed to engraft donor cells and recovered autologous neutrophils on day +39 and day +34, respectively.In the following 8 patients, transplanted between September 2015 and March 2017, we utilized a modified version of the Hopkins protocol with: fludarabine 30mg/m2, Cy 14.5mg/kg, 3 Gy TBI (increased from the original 2 Gy dose), antithymocyte globulin 0.5mg/kg, PT-Cy 50mg/kg, and infusing mobilized PBSC instead of marrow cells (Table 1). G-CSF at 5µg/kg was administered starting on day +12 post-HSCT in neutropenic patients with HbS <30% and the median time to neutrophil engraftment was 22 days (range, 18-23 days). All 8 patients initially engrafted donor cells and only 1 (12%) subsequently developed secondary graft failure. The remaining 7 (88%) currently maintain a stable donor cell engraftment. Transplant related toxicities included: neutropenic fever resolving after antibiotic therapy (n=8/8), ≥ grade II mucositis (n=3/8), CMV reactivation (n=2/8), and small intracranial hemorrhages (n=2/8) on (i) day +10 in a patient refractory to platelet transfusions that resolved after cross-matched platelets became available, and, (ii) on day +12 in a patient with prior stroke history that resolved after increasing the platelet threshold from 50 to 100 x103/µL. Acute GVHD ≥ grade 2 was seen in 2/8 patients (one non-compliant with immunosuppressive treatment), with complete resolution after steroid therapy in one case, and transformation into chronic GVHD (skin, eye and liver) in the other. No other cases of chronic GVHD have been observed to date. With a median follow up of 9 months (range, 5-22 months), all 8 patients are alive and 7 (88%) maintain >90% donor cell chimerism with an improved median hemoglobin concentration from 8.8g/dL (range, 6.4-12.8g/dL) to 13.3g/dL (range, 9.9-15.3g/dL).Our study demonstrates that modifying the Hopkins conditioning regimen by increasing the TBI dose from 2Gy to 3Gy and using PBSC instead of bone marrow grafts allows 88% of SCD patients to achieve stable donor engraftment without severe toxicity. We also demonstrate that G-CSF can be safely administered to adult patients with SCD after HSCT. Haploidentical HSCT is the only curative option for many adult patients with clinically advanced SCD and our study suggests a basis for larger, multicenter clinical studies. [Display omitted] DisclosuresPatel:Celgene: Consultancy, Honoraria. Khan:Takeda: Research Funding; Gilead: Consultancy; Teva: Speakers Bureau. Gordeuk:Emmaus Life Sciences: Consultancy.

Comparison of Outcomes of Post-Transplant Cyclophosphamide between Haplo-Identical and Matched/Mismatched Donor Peripheral Blood Stem Cell Transplantation

Introduction: Haplo-identical donor transplant (HIDT) with post-transplant cyclophosphamide (pCY) has emerged as a potential life-saving treatment modality for patients with limited donor availability. Although HIDT using bone marrow grafts with reduced intensity conditioning regimen has shown promising results, the data on peripheral stem cells are limited. In addition, very little is known about outcomes of cytokine release syndrome (CRS) in this population. We aimed to compare outcomes of pCY graft vs. host disease (GVHD) prophylaxis between HIDT (group 1) and mismatched unrelated, matched unrelated and related transplant (group 2) using peripheral hematopoietic stem cells transplants (PHSCT).Methods: We retrospectively reviewed consecutive adult patients with hematologic malignancies who underwent HIDT (group 1), mismatched unrelated, matched unrelated and related PHSCT (group 2). All patients received pCY as GVHD prophylaxis either alone or in combination with other agents. The primary objectives were to determine rate of GVHD, non-relapse mortality (NRM), relapse rate, relapse free survival (RFS) and overall survival (OS) in both groups at 1-year.Results: A total of 60 patients underwent peripheral blood stem cell transplant between January 2012 to October 2016. Forty patients received HIDT, whereas 10, 8 and 2 patients received mismatched unrelated, matched unrelated and related PHSCT, respectively. The median age of patients was 60.5 years (range, 19-73). AML was the most common diagnosis, followed by MDS and NHL. BU-FLU-TBI (53%) was the most common conditioning regimen used followed by BU-FLU (23%) and FLU-MEL-TBI (10%). The incidence of CRS was 89% in group 1. Grade 1, grade 2, grade 3 and grade 4 CRS was observed in 18 (50%), 9 (25%), 4 (11%) and 1 (3%) patients, respectively. Five patients required tocilizumab and 3 patients received systemic steroids for management of CRS. The median time to neutrophil engraftment was 18 days (range, 12-25) in group 1 and 17 days (range, 13-22) in group 2. The graft failure rate was 10% in each group.The 1-year cumulative incidence of grade III-IV acute GVHD was 7.7% (95% CI, 1.9-19%) in group 1 and 0% in group 2. The 1-year cumulative incidence of chronic GVHD was 21.1% (95% CI, 9.6-35.6%) in group 1 and 41.7% (95% CI, 17.3-64.7%) in group 2. The 1-year cumulative incidence of NRM was 25.2% (95% CI, 12.9-39.5%) in group 1 and 20.0% (95% CI, 6.0-39.9%) in group 2, whereas RFS was 51.5% (95% CI, 37.99-70.06%) in group 1 and 56.8% (95% CI, 37.57-86.11%) in group 2. The 1-year relapse rate was 23.4% (95% CI, 11.3-38%) for group 1 and 23.1% (95% CI, 6.2-46.2%). The median follow-up of living patients was 14.4 months (95% CI, 10.43-23.7) in group 1 and 16.5 months (95% CI, 8.69-NR) in group 2. The 1-year OS was 60.6% (95% CI, 46.76-78.75%) in group 1, and 65% (95% CI, 47.12-89.66%) in group 2. Slightly higher rate of CMV reactivation was observed in group 1 (55% vs 40%, p=0.412), whereas rates of EBV reactivation, C. difficile colitis, invasive fungal and bacterial infections were similar in both groups. No differences in NRM, RFS, relapse rate and OS were found between both groups in multivariable analyses. No differences in GVHD, NRM and OS were noticed in patients with CRS. Disease recurrence and infections were the most common causes of death.Conclusion: Our study demonstrates that pCY provides comparable rates of GVHD, relapse rate and OS in haplo-identical, mismatched unrelated, matched unrelated and related peripheral blood stem cell transplants. pCY can be used as GVHD prophylaxis to provide good post-transplant outcomes regardless of donor source. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

The Effect of Donor Graft Cryopreservation on Allogeneic Hematopoietic Cell Transplantation Outcomes: A Center for International Blood and Marrow Transplant Research Analysis. Implications during the COVID-19 Pandemic

The COVID-19 pandemic has resulted in the increased use of cryopreserved grafts for allogeneic hematopoietic cell transplantation (HCT). However, information about the effect of cryopreservation on outcomes for patients receiving allogeneic donor grafts is limited. We evaluated outcomes of HCT recipients who received either fresh or cryopreserved allogeneic bone marrow (BM) or peripheral blood stem cell (PBSC) grafts reported to the Center for International Blood and Marrow Transplant Research. A total of 7397 patients were included in the analysis. Recipients of cryopreserved graft were divided into 3 cohorts based on graft source: HLA-matched related PBSC donors (n=1051), matched unrelated PBSC donors (n=678), and matched related or unrelated BM donors (n=154). These patients were propensity score matched with 5514 patients who received fresh allografts. The primary endpoint was engraftment. Multivariate analyses showed no significant increased risk of delayed engraftment, relapse, nonrelapse mortality (NRM), or survival with cryopreservation of BM grafts. In contrast, cryopreservation of related donor PBSC grafts was associated with decreased platelet recovery (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.68 to 0.78; P < .001) and an increased risk of grade II-IV (HR, 1.27; 95% CI, 1.09 to 1.48; P=.002) and grade III-IV (HR, 1.48; 95% CI, 1.19 to 1.84; P < .001) acute graft-versus-host disease. Cryopreservation of unrelated PBSC grafts was associated with delayed engraftment of neutrophils (HR, 0.77; 95% CI, 0.71 to 0.84; P < .001) and platelets (HR, 0.61; 95% CI, 0.56 to 0.66; P < .001) as well as an increased risk of NRM (HR, 1.4; 95% CI, 1.18 to 1.66; P < .001) and relapse (HR, 1.32; 95% CI, 1.11 to 1.58; P=.002) and decreased progression-free survival (HR, 1.36; 95% CI, 1.20 to 1.55; P < .001) and overall survival (OS) (HR, 1.38; 95% CI, 1.22 to 1.58; P < .001). Reasons for cryopreservation were not routinely collected; however, in a subset of unrelated donor HCT recipients, the reason was typically a change in patient condition. Products cryopreserved for patient reasons were significantly associated with inferior OS in multivariate analysis (HR, 0.65; 95% CI, 0.44 to 0.96; P=.029). We conclude that cryopreservation is associated with slower engraftment of PBSC grafts, which may be associated with inferior transplantation outcomes in some patient populations. However, the small numbers in the cryopreserved BM cohort and the lack of information on the reason for cryopreservation in all patients suggests that these data should be interpreted with caution, particularly in the context of the risks associated with unexpected loss of a graft during the pandemic. Future analyses addressing outcomes when cryopreservation is universally applied are urgently required.

The impact of graft cell source on bloodstream infection in the first 100 days after allogeneic hematopoietic cell transplantation.

Bloodstream infection (BSI) is a major infectious complication after allogeneic hematopoietic cell transplantation (HCT). To clarify the impact of graft cell source on the incidence of BSI after transplantation, we retrospectively examined 782 adult patients receiving their first allogeneic HCT: 122 recipients of related peripheral blood stem cells or bone marrow, 215 recipients of unrelated bone marrow, and 445 recipients of unrelated umbilical cord blood (U-CB). The cumulative incidence of BSI was 42.5% at 100 days after transplantation (95% confidence interval, 39.0-46.0). Gram-positive cocci were present in 64.2% of detected isolates. Among the pre-transplant factors including age, performance status, primary disease, disease status, graft cell source, sex and ABO blood type matching, and the intensity of conditioning regimen, U-CB use was identified as the most significant risk factor for BSI by multivariate analysis (hazard ratio, 1.76; 95% confidence interval, 1.40-2.22; p < 0.00001). Among the U-CB recipients, those who are not in remission at the time of transplantation were at the greatest risk of BSI (hazard ratio, 1.69; 95% confidence interval, 1.14-2.50; p < 0.01). The study makes it clear that graft cell source has an impact on BSI development after allogeneic HCT.

Effect of donor type on volume of blood transfusions required after allogeneic hematopoietic cell transplantation.

We reviewed blood product use in 729 consecutive allogeneic hematopoietic cell transplantation (allo-HCT) recipients at our center to assess the volume of red blood cells (RBCs) and platelets required after allo-HCT. The median number of bags required by day 30 was 4 for RBCs (range 0-22) and 9.5 for platelets (0-53). Multivariate analysis showed that related peripheral blood stem cell transplantation (PBSCT) required a significantly lower RBC transfusion volume by day 30 compared to unrelated bone marrow transplantation (UBMT). PBSCT from haplo-identical related donors and cord blood transplantation (CBT) required a significantly greater RBC transfusion volume. For platelet transfusion, related and unrelated PBSCT required a significantly lower volume than UBMT, and CBT a greater volume. Other factors independently associated with greater RBC transfusion volume were male sex, disease status other than complete remission, and major ABO mismatch. For platelet transfusion, these were male sex, disease status, and HCT-specific comorbidity index of 1. Although the burden of blood transfusions may not be the most important factor when choosing a donor type, our findings may provide a foundation for nationwide strategies to prepare blood products and inform aspects of national healthcare expenditures.

Impact of Cryopreservation of Donor Grafts on Outcomes of Allogeneic Hematopoietic Cell Transplant (HCT)

Introduction: Cryopreservation of peripheral blood stem cell (PBSC) or bone marrow (BM) grafts is rarely performed, thus information about the effect of cryopreservation on graft characteristics and HCT outcomes is limited. Given the global pandemic leading to changing practices for donor graft collection and increasing utilization of cryopreservation, we evaluated the outcomes of HCT recipients who received either fresh or cryopreserved allogeneic BM or PBSC grafts. The primary endpoint was engraftment. Secondary endpoints were incidence of acute graft-vs.-host disease (aGVHD), relapse, transplant related mortality (TRM), disease free survival (DFS), and overall survival (OS). Methods: We included 7397 patients transplanted between 2013 and 2018. 1883 cryopreserved graft recipients were divided into three cohorts based on graft source and donor type: matched related (MRD) PBSC (n=1,051), matched unrelated (MUD) PBSC (n=678), and matched related or unrelated bone marrow donors (n=154). All patients received conventional calcineurin-based GVHD prophylaxis strategies. Patients who received cryopreserved grafts were matched with 5514 patients who received fresh adjusting for graft type (BM vs. PB), donor source (MRD vs. 8/8 MUD), Disease Risk Index (DRI, low risk vs. intermediate risk vs. high risk), recipient age (within 5-years) and propensity score (within 1 standard deviation from pooled sample). The propensity score was based on age, Karnofsky score, diagnosis, disease risk index, HCT-comorbidity index, and conditioning intensity. The level of statistical significance for the main analyses was p&amp;lt;0.01 due to multiple comparisons. The reason for cryopreservation was available on a subset of URD product recipients. Results: Baseline characteristics for all cohorts are shown in Table 1. CD34+ doses reflect enumeration at infusion. In univariate analyses, rates of graft failure and neutrophil recovery at day 28 were similar for cryopreserved and fresh grafts for BM or related PBSC recipients but differed in cryopreserved vs. fresh MUD PBSC (5% vs 2%, p&amp;lt;0.001 and 87 vs 94%, p&amp;lt;0.001, respectively). Rates of platelet recovery within 28 days were similar in marrow cohorts, but lower with cryopreserved related (92% vs 96%, p&amp;lt;0.001) and MUD PBSC (87 vs 94%, p&amp;lt;0.001) grafts. In matched pair multivariable analyses, there were no significant differences in any outcomes with cryopreserved vs fresh BM grafts, irrespective of donor type. With related donor PBSC, cryopreservation was associated with decreased platelet recovery (HR=0.73, CI=0.68-0.78, p&amp;lt;0.001) and an increased risk of both grade II-IV (HR=1.27, CI=1.09-1.48, p=0.002) and grade III-IV (HR=1.48, CI=1.19-1.84, p&amp;lt;0.001) aGVHD, but had no impact on other outcomes. In contrast, with MUD PBSC grafts, cryopreservation was associated with delayed engraftment of neutrophils (HR=0.77, CI=0.71-0.84, p&amp;lt;0.001) and platelets (HR=0.61, CI=0.56-0.66, p&amp;lt;0.001), an increased risk of TRM (HR=1.4, CI=1.18-1.66, p&amp;lt;0.001) and relapse (HR=1.32, CI=1.11-1.58, p=0.002), and decreased DFS (HR=1.36, CI=1.20-1.55, p&amp;lt;0.001) and OS (HR=1.38, CI=1.22-1.58, p&amp;lt;0.001) but did not affect the incidence of aGVHD. In a subset analysis of 299 URD recipients, the most common reason for cryopreservation was delays due to patient-related events, eg., additional chemotherapy, infection. These recipients had decreased OS compared to products cryopreserved for non-patient reasons (HR=0.65, CI=0.44-0.96, p=0.029). Conclusions: The retrospective nature of this analysis, and the fact that cryopreservation is likely to have been performed in recipients with a different (higher) risk profile compared to those receiving fresh products limits our ability to draw firm confusions. Despite these limitations, we conclude that cryopreservation in some patient populations may have a negative impact on engraftment and transplant outcomes. The decision to cryopreserve donor grafts, particularly PBSC grafts, should be carefully considered and highlights the need for further investigation of the effect of cryopreservation of allogeneic grafts where patient factors can be controlled for. Disclosures Farhadfar: CSL Behring: Research Funding; Incyte pharmaceutical: Other: Member of GVHD advisory forum. Frey:Kite Pharma: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Syntax: Consultancy, Honoraria. Devine:Magenta Therapeutics: Consultancy. Shaw:Orca Bio: Consultancy. Wingard:Shire: Other: Personal Fees - serve on data monitoring committee for clinical trial; Ansun: Other: Personal Fees - serve on data monitoring committee for clinical trial; Merck: Other: Personal Fees - serve on data monitoring committee for clinical trial; Cidara: Other: Personal Fees - serve on data monitoring committee for clinical trial; ReViral: Other: Personal Fees - serve on data monitoring committee for clinical trial.

GVHD-free, relapse-free survival provides novel clues for optimizing allogeneic-HSCT for adult T-cell leukemia/lymphoma

The outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for adult T-cell leukemia/lymphoma (ATL) is still unsatisfactory. To illustrate the advantages and disadvantages of each donor source, we performed a nationwide retrospective study of graft-versus-host disease (GVHD)-free, relapse-free survival (GRFS) of patients with allo-HSCT-treated ATL. One-year GRFS did not significantly differ between patients who received related bone marrow transplantation (R-BMT; 26%, n = 117), related peripheral blood stem cell transplantation (R-PBSCT; 22%, n = 225), unrelated bone marrow transplantation (UR-BMT; 26%, n = 619), and cord blood transplantation (CBT; 21%, n = 359; p = 0.09). This was attributable to a low incidence of systemically-treated chronic GVHD after CBT (9% at 1 year) and reduced non-GVHD/relapse mortality after R-PBSCT (9% at 1 year). Among patients transplanted in complete remission (CR), 1-year overall survival after CBT (52%, n = 132) was not inferior to that after R-BMT (55%, n = 51), R-PBSCT (57%, n = 79), and UR-BMT (58%, n = 280; p = 0.15), and relapse rates were equivalent among the four sources (p = 0.19). Our results suggest that all donor sources are feasible for CR patients and that GRFS provides important clues toward optimizing allo-HSCT for ATL.

Graft-Versus-Host Disease-Free, Relapse-Free Survival in Allogeneic Stem Cell Transplantation for Adult T-Cell Leukemia/Lymphoma Provides a Novel Donor Selection Paradigm

Background: Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) can provide sustained remission for adult T-cell leukemia/lymphoma (ATL), its prognosis is still unsatisfactory. Alternative donor sources are often utilized in allo-HSCT for ATL, but advantages and disadvantages of each donor source have not been fully elucidated. Graft-versus-host disease (GVHD) -free, relapse-free survival (GRFS) has been proposed as a novel and clinically meaningful endpoint of allo-HSCT. Whereas GVHD has been relatively accepted in ATL to induce substantial graft-versus-tumor (GVT) effects, severe GVHD is associated with non-relapse mortality and disturbs quality of patients' life. Analyses of GRFS may illustrate important aspects to optimize the balance between regulating GVHD and enhancing GVT effects in ATL patients. Patients and methods: We retrospectively analyzed the data of 1363 patients with ATL who received first allo-HSCT from 2006 through 2015 in Japan. Data were collected from the nationwide database maintained by the Japan Society of Hematopoietic Cell Transplantation. The probability of OS and GRFS was estimated according to the Kaplan-Meier method, and univariate comparisons among the groups were performed using the log-rank test. The Cox proportional hazard model was used for the multivariate analysis of OS and GRFS. Results: Median age was 57 years-old (range: 20-78) and median observation period of survivors was 3.1 years (range: 0.0-10.5). One-year OS and GRFS were 45% and 24%, respectively. OS of cord blood transplantation (CB) (37% at 1 year, n = 359) was worse than those of related bone marrow transplantation (R-BM) (48%, n = 121), related peripheral blood stem cell transplantation (R-PB) (50%, n = 264) and unrelated bone marrow transplantation (UR-BM) (47%, n = 619) (p &lt; 0.001). However, in the cases of complete remission (CR) at allo-HSCT, OS of CB (n = 132) was 52% at 1 year and not inferior to those of R-BM (54%, n = 52), R-PB (57%, n = 88) and UR-BM (58%, n = 280) (p = 0.14). The cumulative incidence of relapse in CB was 47% at 1 year and higher than those of R-BM (40%), R-PB (43%) and UR-BM (35%) (p = 0.002). However, in CR cases, the cumulative incidences of relapse were lower in UR-BM (21% at 1 year) and CB (26%) than those in R-BM (31%) and R-PB (31%), though not significant (p = 0.21). Notably, there were no significant differences in GRFS of CB, R-BM, R-PB and UR-BM (21%, 25%, 21% and 26% at 1 year, p = 0.08, Figure 1A). It was attributed to low incidence of chronic GVHD which needed systemic therapy in CB (9% at 1 year, R-BM: 22%, R-PB: 28% and UR-BM: 18%, p &lt; 0.001, Figure 1B) and low incidence of non-GVHD/relapse mortality in R-PB (9% at 1 year, CB: 20%, R-BM: 13% and UR-BM: 16%, p &lt; 0.001, Figure 1C). In R-BM and UR-BM, there were no significant differences as for OS and GRFS between HLA-matched and HLA-mismatched transplantations. In R-PB, OS of HLA haploidentical transplantation (Haplo, n = 36) was 39% at 1 year and tended to be inferior to those of HLA 6/6-matched (53%, n = 183) and HLA 5/6-matched transplantation (49%, n = 45) (p = 0.11). There was no significant difference as for GRFS among these 3 groups (Haplo: 22%, 6/6-matched: 20%, 5/6-matched: 27% at 1 year, p = 0.69). Finally, multivariate analysis revealed that male sex, higher age (&gt; 50 years), worse PS (&gt; 1) and non-CR at allo-HSCT were associated with lower OS and GRFS. Importantly, donor sources and HLA mismatch were not associated with OS and GRFS. Conclusions: Our results imply that all donor sources are feasible for CR cases and can be selected depending on their clinical characteristics such as frailty and history of infection. While the main issue of CB is high non-GVHD/relapse mortality, it is warranted to suppress severe GVHD in R-PB. Thus, GRFS provides important clues to improve the outcome of allo-HSCT for ATL. Figure Disclosures Shindo: Novartis: Research Funding. Nakano:Novartis: Honoraria. Ichinohe:Astellas Pharma: Research Funding; Chugai Pharmaceutical Co.: Research Funding; CSL Behring: Research Funding; Eisai Co.: Research Funding; Kyowa Hakko Kirin Co.: Research Funding; Ono Pharmaceutical Co.: Research Funding; Pfizer: Research Funding; Nippon Shinyaku Co.: Research Funding; MSD: Research Funding; Otsuka Pharmaceutical Co.: Research Funding; Repertoire Genesis Inc.: Research Funding; Sumitomo Dainippon Pharma Co.: Research Funding; Taiho Pharmaceutical Co.: Research Funding; Takeda Pharmaceutical Co.: Research Funding; Zenyaku Kogyo Co.: Research Funding; Alexion Pharmaceuticals: Honoraria; Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; JCR Pharmaceuticals: Honoraria; Janssen Pharmaceutical K.K.: Honoraria; Mundipharma: Honoraria; Novartis: Honoraria. Atsuta:CHUGAI PHARMACEUTICAL CO., LTD.: Honoraria; Kyowa Kirin Co., Ltd: Honoraria.

Risk Factors and the Therapeutic Efficacy for Thrombotic Microangiopathy in Patients after Allogeneic Hematopoietic Stem Cell Transplantation - Results of the Multicenter Retrospective Cohort Study

[Introduction] Transplant-associated thrombotic microangiopathy (TA-TMA) is a fatal complication after allogeneic hematopoietic stem cell transplantation (HSCT). However, given its relatively low incidence, no large cohort-based study has determined TA-TMA risk factors and its impact on overall survival (OS) or the most effective therapeutic interventions. Recombinant human soluble thrombomodulin (rTM) is a promising therapeutic option; with dual antithrombosis and anti-inflammation activities, a single-center small cohort study in Japan reported rTM to be effective against TA-TMA. This study aimed to clarify risk factors for TA-TMA development and the efficacy of various TA-TMA therapies in a multicenter large cohort. [Methods] This retrospective cohort study conducted by the Kyoto Stem Cell Transplantation Group enrolled adult patients (age ≥ 16 years) with hematological diseases who underwent allogenic HSCT after 2000. Cumulative TA-TMA incidence was calculated using Gray's test; death from any cause was a competing risk. We evaluated OS in patients with or without TA-TMA using the Simon-Makuch method and compared it using the Cox proportional hazard model with TA-TMA development as a time-dependent covariate. Correlations were analyzed between each pre- or post-transplant factor and TA-TMA development using Gray's test. Factors significant in the univariate analysis were subjected to the multivariate analysis using the Fine-Gray proportional hazards model. We evaluated the effect of each therapeutics on response using a logistic regression model. [Results] We enrolled 2,430 patients [median age at HSCT, 50 (range: 16-74) years] from 14 institutes. Overall, 1,234 patients were transplanted for acute myeloid leukemia or myelodysplastic syndrome, followed by acute lymphoblastic leukemia (n = 381) and non-Hodgkin lymphoma (n = 351). Overall, 1,219 patients (50.2%) had advanced disease (non-remission status) at HSCT. The HCT-CI score was higher (≥3) in 213 patients (8.8%), and 360 (14.8%) were transplanted at poorer performance statuses (PS 2-4). In total, 471 patients (19.4%) received related bone marrow transplantation (BMT), 423 (17.4%) received related peripheral blood stem cell transplantation (PBSCT), 871 (35.8%) unrelated-BMT, and 665 (27.4%) unrelated cord blood transplantation. HLA was mismatched in 1,461 (60.1%) patients. After HSCT, TA-TMA was observed in 123 patients; the cumulative incidence of TA-TMA 12 months after HSCT was 5.0%; TA-TMA occurred at a median of 36 days (range: 3-482) (Figure 1). TA-TMA was correlated with a remarkably inferior OS [hazard ratio (HR), 4.93; 95% confidence interval (CI), 4.03-6.02; P &lt; 0.001] when treating TA-TMA as a time-dependent covariate. In the multivariate analysis, poorer PS [HR, 1.64; 95% CI, 1.05-2.58; P = 0.03], higher HCT-CI [HR, 1.70, 95% CI, 1.02-2.83; P = 0.04], and HLA-mismatch [HR, 2.06; 95% CI, 1.34-3.17; P = 0.001] were significant pre-transplantation risk factors for TA-TMA. Post-transplantation factors (acute GVHD (Grade 3-4) [HR, 2.51; 95% CI, 1.64-3.85; P &lt; 0.001] and veno-occlusive disease (VOD/SOS) [HR, 3.70; 95% CI, 2.05-6.70; P &lt; 0.001]) were also significant risk factors for TA-TMA in the multivariate analysis. No infections (bacterial, viral, or fungal) were significantly related to TA-TMA incidence. Regarding therapeutic interventions, 36 (29.3%) patients received rTM-including treatment, 6 (5%) were treated with rTM alone, and 30 (24.4%) were treated with rTM and FFP (14; 11%), PE (5; 4%), or both FFP and PE (11; 9%). No significant differences in response rate [OR, 0.99; 95% CI, 0.39-2.52; P = 0.98] and OS [HR, 0.93; 95% CI, 0.58-1.49; P = 0.77] between the groups treated with or without rTM were identified. The results showed similar trends in other therapeutic interventions. [Conclusion] This study clarified the incidence of TA-TMA, its impact on clinical outcomes, risk factors including post-transplantation factors, and therapy efficacies. Patients with poor PS, high HCT-CI scores, and HLA-mismatched donors were high-risk patients; the development of severe acute GVHD and VOD/SOS also increased the risk of TA-TMA. rTM administration or other treatments did not improve patient outcomes. Therefore, strategies to avoid TA-TMA are essential. Intensification of the GVHD and VOD/SOS prophylaxis or treatment for these high-risk patients may reduce TA-TMA and improve HSCT outcomes. Figure 1 Disclosures Imada: Novartis Pharma K.K.: Honoraria; Takeda Pharmaceutical Co.,LTD.: Honoraria; Celgene K.K.: Honoraria; Bristol-Meyer Squibb K.K.: Honoraria; Otsuka Pharmaceutical Co., Ltd.: Honoraria; Ono Pharmaceutical Co., Ltd.: Honoraria; Kyowa Hakko Kirin Co., Ltd.: Honoraria; Astellas Pharma Inc.: Honoraria; Nippon Shinyaku Co.,Ltd.: Honoraria; Chugai Pharmaceutical Co., Ltd.: Honoraria. Takaori-Kondo:Kyowa Kirin: Research Funding; Chugai: Research Funding; Takeda: Research Funding; Ono: Research Funding; Novartis: Honoraria; Celgene: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Janssen: Honoraria; Pfizer: Honoraria.

Time-Varying Effects of Graft Type on Outcomes for Patients with Acute Myeloid Leukemia Undergoing Allogeneic Hematopoietic Cell Transplantation

This study aimed to investigate time-varying effects of graft type on outcomes for patients with acute myeloid leukemia undergoing allogeneic hematopoietic cell transplant. For this purpose we analyzed 3952 patients, 720 of whom underwent matched related bone marrow transplantation (BMT), 1004 matched related peripheral blood stem cell transplantation (PBSCT), 856 matched unrelated BMT, and 1372 umbilical cord blood transplantation (UCBT) during complete remission. The 4-year relapse-free survival (RFS) rates were 59.1%, 52.8%, 59.5%, and 50.6%, respectively. Compared with related BMT, related PBSCT, unrelated BMT, and UCBT were associated with higher risk of nonrelapse mortality and unrelated BMT and UCBT with lower risk of relapse. As a result, both RFS and overall survival were comparable between related BMT and unrelated BMT but were worse for related PBSCT and UCBT than for related BMT. Adverse impact of UCBT was observed only during the early phase of transplant, whereas that of related PBSCT continued even after 2 years post-transplant. Our findings raise concerns about the increased risk of late nonrelapse mortality with the use of PBSC grafts and suggest that related BMT is preferable to related PBSCT; matched unrelated BMT is the next choice in the absence of a matched related donor.

Comparison of Outcomes of Allogeneic Hematopoietic Cell Transplantation for Primary Myelofibrosis Among Stem Cell Source Groups

Allogeneic hematopoietic cell transplantation (HCT) is the only treatment modality that can either cure or prolong life of patients with primary myelofibrosis (PMF). However, the issues of the choice of stem cell source, the choice of conditioning regimen, and the timing of HCT are currently under debate. To determine whether a difference in stem cell source affects the outcome of HCT for PMF patients, a retrospective study was conducted using the national registry data on 224 patients who received first allogeneic HCT in Japan with bone marrow (BM), peripheral blood stem cells (PBSC) or umbilical cord blood (UCB). This study was approved by the Data Management Committee of the Japan Society for Hematopoietic Cell Transplantation and by the ethics committee of the Nagoya University School of Medicine. One hundred fifty-two male and 72 female, with a median age of 55 years (range, 21-79 years), were treated with a myeloablative (48%) or non-myeloablative (52%) preconditioning and GVHD prophylaxis such as calcineurin inhibitor with methotrexate (78%) between 1993 and 2016. Stem cell sources were HLA-A, -B and -DR 6/6 matched related BM (Rtd-BM) (n = 22), HLA-A, -B and -DR 6/6 matched related PBSC (Rtd-PBSC) (n = 48), HLA-A, -B, -C and -DRB1 alleles 8/8 or 7/8 matched unrelated BM (UR-BM) (n = 91), unrelated UCB (UR-UCB) (n = 29) and others (n = 34) including HLA 5/6 or 4/6 matched related BM and PBSC, HLA-haploidentical related BM and PBSC, HLA alleles 6/8 or 5/8 matched unrelated BM, and HLA alleles 8/8 or 7/8 matched unrelated PBSC. All UR-UCB transplantation was performed with a single unit. The median follow-up term for living patients was 48 (0.3-202) months. Cumulative incidences of neutrophil recovery (≥0.5 × 109/L) on day 60 were 100% in Rtd-BM (median days to recovery, 21 days), 94% in Rtd-PBSC (16 days), 86% in UR-BM (21 days), 79% in UR-UCB (25 days) and 91% in other transplantation (23 days). Cumulative incidences of grade II-IV and III-IV acute GVHD on day 100 were 23% and 5% in Rtd-BM, 27% and 19% in Rtd-PBSC, 27% and 10% in UR-BM, 31% and 10% in UR-UCB, and 26% and 15% in other transplantation, respectively. Cumulative incidences of chronic GVHD at 2 years after HCT were 35% in Rtd-BM, 41% in Rtd-PBSC, 34% in UR-BM, 19% in UR-UCB and 13% in other transplantation. Non-relapse mortality (NRM) at 2 years after HCT were 22% in Rtd-BM, 41% in Rtd-PBSC, 39% in UR-BM, 47% in UR-UCB and 48% in other transplantation. Multivariate analysis demonstrated that RBC transfusion ≥20 times before HCT (HR, 2.05; 95% CI, 1.06-3.98), PLT transfusion 10-19 times before HCT (3.56, 1.57-8.05), UR-UCB transplantation (4.70, 1.13-19.6) and other transplantation (4.38, 1.05-18.3) were predictive factors for higher NRM. Although performance status ≥2 at HCT was significant for higher NRM in univariate analysis, it was not significant in multivariate analysis. Relapse rates at 2 years after HCT were 14% in Rtd-BM, 17% in Rtd-PBSC, 13% in UR-BM, 24% in UR-UCB and 15% in other transplantation. Multivariate analysis demonstrated that no factor was associated with the incidence of relapse, although high-risk group of chromosome karyotype was significant for higher relapse rate in univariate analysis. Neither stem cell source groups nor DIPSS was not significant in univariate analysis. Overall survival (OS) rates at 2 and 5 years after HCT were 71% and 71% in Rtd-BM, 52% and 52% in Rtd-PBSC, 54% and 46% in UR-BM, 43% and 27% in UR-UCB, and 48% and 33% in other transplantation, respectively. Multivariate analysis demonstrated that age of 46-55 years (HR, 2.14; 95% CI, 1.00-4.56) and ≥56 years (2.69, 1.32-5.48), RBC transfusion ≥20 times before HCT (1.91, 1.13-3.25) and PLT transfusion 10-19 times before HCT (3.51, 1.64-7.52) predicted lower OS rate. Although performance status ≥2 at HCT, DIPSS intermediate-2 or high at HCT, high-risk group of chromosome karyotype, UR-UCB transplantation and other transplantation were significant for lower OS in univariate analysis, they were not significant in multivariate analysis. The present study could not find an advantage of use of JAK1/2 inhibitor before HCT, use of anti-thymoglobulin as a preconditioning, and non-myeloablative preconditioning regimen in terms of decreasing NRM or increasing OS rate. Our results suggest that allogeneic HCT provide a curative treatment for PMF patients, however careful management is required in HCT with other than Rtd-BM, Rtd-PB and UR-BM. Further analysis in a large cohort is required. DisclosuresNo relevant conflicts of interest to declare.

The Proportional Association between WT1 mRNA Level in Peripheral Blood before Allogeneic Hematopoietic Cell Transplantation and Risk of Mortality in Acute Myeloid Leukemia Not in Remission

Abstract INTRODUCTION The prognosis for allogeneic hematopoietic cell transplantation (allo-HCT) is relatively poor in patients with acute myeloid leukemia (AML) who are not in remission (non-CR). Wilms' tumor-1 gene messenger ribonucleic acid (WT1 mRNA), which is overexpressed in almost all AML, has been used as an indicator of monitoring minimal residual disease (MRD) and has been regarded as one of the prognostic factors in AML patients with complete remission (CR). However, the association between the expression levels of WT1 mRNA in peripheral blood (WT1) before allo-HCT and risk of mortality in AML patients in non-CR remains quite elusive. We therefore assessed the effect of the pre-transplant WT1 level on survival after allo-HCT in AML patients in non-CR. METHODS We retrospectively analyzed data from consecutive patients undergoing allo-HCT at our institution between November 2007 and January 2017. We excluded patients who did not have an available WT1 value within 28 days before the start of conditioning. RESULTS A total of 125 AML patients, including 46 non-CR patients (36.8 %), were eligible for this study. The median age was 48 years (range: 17-68 years) and the number of males was 69 (55.2%). Forty-two patients (33.6%) had AML with myelodysplasia-related changes. This study included 34 patients (27.2%) who had undergone multiple transplantation. Myeloablative and reduced-intensity conditioning were used in 73 (58.4%) and 52 (41.6%) patients, respectively. In 63 patients who received transplants from either a related peripheral blood stem cell or bone marrow (BM) donor, four pairs (6.3%) were serologically mismatched for one antigen of HLA and 45 pairs (71.4%) received transplants from HLA haploidentical donors. In 32 patients who received transplants from an unrelated BM donor, seven pairs (21.9%) were serologically mismatched for one HLA antigen. Twenty-nine patients (23.2%) received unrelated cord blood transplantation. Among 46 non-CR patients, the median follow-up period among survivors was 1,092 days (range: 688-2,607 days) following allo-HCT. Receiver operating characteristic analysis for prediction of composite events including any cause of death or subsequent transplantation indicated that the best cutoff value for WT1 was 5,000 copies/ μg RNA in non-CR AML patients. Estimated two-year, event-free survival of non-CR patients with WT1 levels of less than 5,000 copies/ μg RNA was significantly higher than that of those with WT1 levels of 5,000 copies/ μg RNA or more (41.2% [95% confidence interval (CI), 18.6-62.6] vs 10.3% [95% CI, 2.6-24.3]; P=0.006). On multivariate analysis of the non-CR patients, WT1 5,000 copies/ μg RNA or more was significantly associated with increased risk of mortality (hazard ratio (HR), 2.7; 95% CI, 1.3-5.5; P=0.008). Log10-transformed WT1 (continuous scale) was also significantly related to increased risk of mortality (HR, 1.5; 95% CI, 1.0-2.1; P=0.037). In the entire cohort, log10-transformed WT1 (divided into four categories) before allo-HCT was found to be the most powerful prognostic factor of survival among remission status, cytogenetic risk group, and revised disease risk index, applying Akaike's information criterion. Moreover, under the assumption of a non-linear model, as the log10-transformed WT1 level rose, the HR of mortality increased monotonically; a non-linear fit was obtained using a restricted cubic spline function (three knots; Figure 1). CONCLUSION Our data showed that WT1 levels obtained before allo-HCT monotonically increased HR of mortality in a non-linear manner regardless of CR status. Of importance is the finding that WT1 levels before allo-HCT were proportionally correlated with probability of survival after allo-HCT in non-CR AML patients. This suggests that the level of expression of WT1 mRNA in peripheral blood might reflect tumor burden and that there may be a WT1 threshold in non-CR patients for benefiting from allo-HCT. Further prospective studies of WT1 are necessary to determine acceptable or feasible levels of disease activity for receiving allo-HCT in relapsed or refractory AML patients. Disclosures Nakamae: Otsuka Pharmaceutical Co., Ltd.: Consultancy, Honoraria, Research Funding. Hino:Otsuka Pharmaceutical Co., Ltd.: Research Funding; Novartis: Research Funding. Nakamae:Otsuka Pharmaceutical Co., Ltd.: Consultancy, Honoraria, Research Funding.

The Effect of Aging and Pre-Donation Comorbidities on the Related PBSC Donor Experience: A Report from the Related Donor Safety Study (RDSafe)

Background: The development of reduced intensity approaches for allogeneic hematopoietic cell transplantation has resulted in growing numbers of older related donors (RD) of PBSC. The effects of age on donation efficacy, toxicity, and long-term recovery in RD are poorly understood. Methods: We analyzed hematologic variables, pain, donation-related symptoms and recovery in 1211 related PBSC donors aged 18-79 enrolled in the Related Donor Safety Study (RDSafe). Results: RD >60 had a lower median CD34 level pre-apheresis compared to younger RD (age >60, 59x106/L; age 41-60, 81x106/L; age 18-40, 121x106/L; p 24L, p 60 with post-collection thrombocytopenia <50x109/L (26% and 57% after 2 and 3 days of collection, respectively). RD age 18-40 had a higher risk of grade 2-4 pain and symptoms peri-collection, burrt donors above age 40 had more persistent pain at 1, 6, and 12 months (OR1.7, p=0.02) and a higher rate of non-recovery to pre-donation levels (OR 1.7, p=0.01). Donors reporting comorbidities increased significantly with age, and those with comorbidities that would have led to deferral by NMDP unrelated donor standards had an increased risk for persistent grade 2-4 pain (OR=2.41, p<0.001) and failure to recover to pre-donation baseline for other symptoms (OR=2.34, p=0.004). Conclusion: This information should be used in counseling RD regarding risk and can assist in developing practice approaches aimed at improving the RD experience for high-risk individuals. Funding Statement: This study was funded by R01 HL085707 through the NHLBI. Additional funding for MAP was provided by 2UG1HL069254 (NHLBI/NCI) and the Johnny Crisstopher Children’s Charitable Foundation St. Baldrick’s Consortium Grant. Conflict of Interests: None of the authors has any conflict of interest to declare. Ethical Approval Statement: If approved for donation, RD were approached for consent for this IRB approved study if they were willing and able to complete symptom reviews at 1, 6 and 12 months after donation administered by the CIBMTR Survey Research Group.

High Disease-Free and Overall Survival Rate Following Allogeneic Hematopoietic Stem Cell Transplantation for FLT3-Mutated Acute Myeloid Leukemia Even in Non-Remission Status

[Background] FMS like tyrosine kinase 3 (FLT3) mutations occur in about 30% of patients with acute myeloid leukemia (AML). Patients with FLT3-mutated AML have a poor prognosis and are referred for early allogeneic hematopoietic stem cell transplantation (allo-HSCT) in first complete remission (CR1). So far, there is still limited data available on allo-HSCT for FLT3-mutated AML in non-remission status.[Objective and method] To assess the clinical features and outcome of allo-HSCT for FLT3-mutated AML, we retrospectively analyzed patients underwent first allo-HSCT for FLT3-mutated AML excluding acute promyelocytic leukemia (FAB M3) from January 2011 to March 2016.[Result] During the study period, 332 patients received first allo-HSCT for AML in our institute. One hundred and thirty-eight were tested for the presence of FLT3-mutation and 35 showed positive results and were subjected to the analysis. The median follow-up day of survivors was 602 (101-1867). The median age of the patients was 55 years (range, 21-72). Twenty-one patients had de novo AML, 12 had AML with myelodysplasia related changes, and 2 had therapy related AML. Eighteen had normal karyotype, 4 had complex, and 13 had others. Seven were in remission (5 in CR1, and 2 in CR2), and 28 were in non-remission (8 in primary induction failure, 13 in relapse 1, and 7 in chemo naïve status). Twenty-nine patients used unrelated cord blood, 2 did unrelated bone marrow, and 4 did related peripheral blood stem cell as grafts. All but 1 received myeloablative pretransplant conditionings. At 2 years after transplantation, overall survival (OS), disease free survival (DFS), relapse rate (RR), and non-relapse mortality (NRM) of whole studied population were 65.9%, 50.2%, 28.4%, and 21.4%, respectively. Among those in non-remission before transplantation, OS, DFS, RR, and NRM at 2 years post-transplant were 62.2% (Figure 1A), 49.9%(Figure 1B), 24.3%, and 25.8%, respectively. Only younger age (<55 years) was the factor associated with better OS with statistical significance in multivariate analysis.[Conclusion] Our data indicated that allo-HSCT could overcome the poor prognosis of FLT3-mutated AML even for those in non-remission status, despite the profound chemo-resistant character of FLT3-mutated AML. [Display omitted] [Display omitted] DisclosuresIzutsu:Abbvie: Research Funding; Gilead: Research Funding; Celgene: Research Funding; Janssen Pharmaceutical K.K.: Honoraria; Eisai: Honoraria; Kyowa Hakko Kirin: Honoraria; Chugai Pharmaceutical: Honoraria, Research Funding; Takeda Pharmaceutical: Honoraria; Mundipharma KK: Research Funding.