Post-Transplantation Cyclophosphamide-Based Graft-versus-Host Disease Prophylaxis in HLA-Matched and Haploidentical Donor Transplantation for Patients with Hodgkin Lymphoma: A Comparative Study of the Lymphoma Working Party of the European Society for Blood and Marrow Transplantation.

Post-transplantation cyclophosphamide (PTCy) has emerged as a promising approach for preventing graft-versus-host disease (GVHD) in allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, there is a lack of studies examining the impact of this GVHD prophylaxis when different donor types are used in patients with Hodgkin lymphoma (HL). This study compared the outcomes of patients with HL undergoing HSCT from HLA-matched donors, including matched sibling donors (MSDs) and matched unrelated donors (MUDs), and haploidentical donors, using PTCy as the GVHD prophylaxis approach in all cohorts. We retrospectively compared outcomes of allo-HSCT from 166 HLA-matched donors (96 sibling and 70 unrelated donors) and 694 haploidentical donors using PTCy-based GVHD prophylaxis in patients with HL registered in the European Society for Blood and Marrow Transplantation database from 2010 to 2020. Compared to HLA-matched HSCT, haploidentical donor HSCT was associated with a significantly lower rate of platelet engraftment (86% versus 94%; P < .001) and a higher rate of grade II-IV acute GVHD (34% versus 24%; P = .01). The 2-year cumulative incidence of nonrelapse mortality (NRM) was significantly lower in the HLA-matched cohort compared to the haploidentical cohort (10% versus 18%; P = .02), resulting in a higher overall survival (OS) rate (82% versus 70%; P = .002). There were no significant differences between the 2 cohorts in terms of relapse, progression-free survival, or GVHD-free relapse-free survival. In multivariable analysis, haploidentical HSCT was associated with an increased risk of grade II-IV acute GVHD and NRM and worse OS compared to HLA-matched HSCT. Our findings suggest that in the context of PTCy-based GVHD prophylaxis, transplantation from HLA-matched donors appears to be a more favorable option compared to haploidentical HSCT.

Second haploidentical stem cell transplantation (HAPLO-SCT2) after relapse from a first HAPLO-SCT in acute leukaemia-a study on behalf of the Acute Leukaemia Working Party (ALWP) of the European Society for Blood and Marrow Transplantation (EBMT).

For patients with acute myeloid and lymphoblastic leukaemia (AML/ALL) lacking a matched sibling or unrelated donor, haploidentical stem cell transplantation (HAPLO-SCT) is increasingly used. However, available data on the treatment of relapse after HAPLO-SCT, including feasibility and efficacy of a second HAPLO-SCT (HAPLO-SCT2), is scarce. Hence, adults with AML/ALL, that had undergone HAPLO-SCT2 without ex-vivo manipulation after haematologic relapse from HAPLO-SCT1 were selected for a retrospective registry analysis. Eighty-two patients (AML, n = 63, ALL, n = 19, median follow-up: 33 months) were identified. Engraftment rate was 87%. At day +180, cumulative incidences of acute GvHD II-IV°/chronic GvHD were 23.9%/22.6%, respectively. Two-year overall survival/leukaemia-free survival (OS/LFS) were 34.3%/25.4%; 2-year non-relapse mortality (NRM) and relapse incidence (RI) were 17.6% and 57%. Leukaemia was the most frequent cause of death. Separated by disease, 2-year OS/LFS/NRM/RI were 28.7%/22.3%/16.2%/61.6% in AML, and 55.3%/38.4%/23.5%/38.2% in ALL patients. In a risk-factor analysis among patients with AML, stage at HAPLO-SCT1 and HAPLO-SCT2, and interval from HAPLO-SCT1 to relapse significantly influenced outcome. Our data demonstrate that HAPLO-SCT2 is a viable option in acute leukaemia relapse after HAPLO-SCT1. Engraftment, toxicity, risk factors and long-term outcome are comparable to data reported after allo-SCT2 in a matched donor setting.

Feasibility of a Hospital-at-Home Program for Autologous Hematopoietic Stem Cell Transplantation.

The Hospital at Home (HaH) model has been positioned as an appropriate therapeutic strategy for selected patients undergoing autologous hematopoietic stem cell transplantation (ASCT). This care model provides hospital-equivalent care, in terms of both quality and quantity, with medical and nursing staff that go to the patient's home. Here we describe our experience with a full HaH model for patients undergoing ASCT during the phase of aplasia. The patients met the eligibility criteria between January 1997 and December 2019 and were discharged from the hospital and admitted into the HaH-ASCT program on the same day they in which hematopoietic stem cells were infused. A total of 84 patients were included. The median patient age was 54 years (range, 16 to 74 years), and the median duration of participation in the HaH program was 17 days (range, 3 to 86 days). Only 10 of these patients (12%) required hospital readmission to the hematology department, 9 of them due to sepsis and 1 because of family care support claudication. Seventy-two patients (86%) experienced an episode of neutropenic fever during the HAH admission, with a median duration of 2 days (interquartile range [IQR], 1 to 11 days); all were treated with empiric i.v. antimicrobial therapy. Most patients (88%) presented with mucositis (44% with grade 3-4). Parenteral nutrition was administered in 26% of patients for a median of 6 days (IQR, 1 to 12 days). Most patients (94%) required at least 1 blood product transfusion at home. There was no transplantation-related mortality during the HaH-ASCT program or in the patients who were readmitted. With careful selection of patients and a comprehensive and well- experienced multidisciplinary team (doctors, nurses, and auxiliary nurses) in the HaH department and in close collaboration with the hematology department, complete at-home management of ASCT recipients immediately after transplantation is possible. This allows patients undergoing an aggressive procedure such as ASCT to remain in their own familiar environment, providing a better quality of life with a program that has demonstrated to be effective and safe, with a low incidence of complications and no associated mortality.

Ponatinib, chemotherapy, and transplant in adults with Philadelphia chromosome-positive acute lymphoblastic leukemia.

Promising results have been shown with the combination of ponatinib and chemotherapy in adults with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). The PONALFIL (Ponatinib With Chemotherapy for Young Adults Ph Positive Acute Lymphoblastic Leukemia) trial combined ponatinib (30 mg/d) with standard induction and consolidation chemotherapy followed by allogeneic hematopoietic stem cell transplant (alloHSCT) in newly diagnosed Ph+ ALL patients aged 18 to 60 years. Ponatinib was only given pre-emptively after alloHSCT. Primary end points were hematologic and molecular response before alloHSCT and event-free survival (EFS), including molecular relapse as event. Thirty patients (median age, 49 years; range, 19-59 years) entered the trial. All exhibited hematologic response, and alloHSCT was performed in 26 patients (20 in complete molecular response and 6 in major molecular response). Only 1 patient died (of graft-versus-host disease), and 5 patients exhibited molecular relapse after alloHSCT. No tyrosine kinase inhibitor was given after HSCT in 18 of 26 patients. Twenty-nine patients are alive (median follow-up, 2.1 years; range, 0.2-4.0 years), with 3-year EFS and overall survival (OS) of 70% (95% confidence interval, 51-89) and 96% (95% confidence interval, 89-100), respectively. Comparison of the PONALFIL and the ALLPh08 (Chemotherapy and Imatinib in Young Adults With Acute Lymphoblastic Leukemia Ph [BCR-ABL] Positive; same schedule, using imatinib as the tyrosine kinase inhibitor) trials by propensity score showed significant improvement in OS for patients in PONALFIL (3-year OS, 96% vs 53%; P = .002). The most frequent grade 3 to 4 adverse events were hematologic (42%), infectious (17%), and hepatic (22%), with only one vascular occlusive event. The combination of chemotherapy with ponatinib followed by alloHSCT is well tolerated, with encouraging EFS in adults with newly diagnosed Ph+ ALL. Cross-trial comparison suggests improvement vs imatinib (clinicaltrials.gov identifier #NCT02776605).

Post-Transplantation Cyclophosphamide After HLA Identical Compared to Haploidentical Donor Transplant in Acute Myeloid Leukemia: A Study on Behalf of GETH-TC.

Post-transplantation cyclophosphamide (PTCY) effectively prevents graft-versus-host disease (GVHD) after unmanipulated HLA-haploidentical hematopoietic stem cell transplantation (HSCT) and achieves low rates of GVHD in HLA-identical transplantation. To compare the outcomes of haploidentical versus HLA identical HSCT in patients undergoing HSCT for acute myeloid leukemia (AML) using PTCY. We conducted a retrospective study of 229 patients undergoing first HSCT for AML using PTCY with additional immunosuppression, 99 from matched sibling or unrelated donor (MSD/MUD) performed in 3 hospitals and 130 from haploidentical donors (haplo group) performed in 20 hospitals within the Spanish Group of Hematopoietic Stem Cell Transplantation and Cellular Therapy. Peripheral blood stem cells were used as graft in 89% of patients; myeloablative conditioning was used in 56%. There were significantly more patients with active disease (5% versus 20%, P = .001), high/very high disease risk index (DRI) (32% versus 67%, P = .000) and prior auto-HSCT (2% versus 11%, P = .010) in the haplo group. Median follow-up was 27 and 62.5 months for MSD/MUD and haplo, respectively. At 2 years, no significant differences were observed in overall survival (OS) (72% versus 62%, P = .07), event-free survival (EFS) (70% versus 54%, P = .055), cumulative incidence of relapse (19% versus 25%, P = .13), non-relapse mortality (14% versus 19%, P = .145), and the composite endpoint of GVHD and relapse-free survival (49% versus 42%, P = .249). Multivariate analysis identified only age and active disease as significant risk factors for OS and EFS; reduced-intensity conditioning, high/very high DRI, and haplo donor were nearly statistically significant for these outcomes. Grade II-IV acute GVHD was lower in MSD/MUD (14% versus 47%, P = .000). Cumulative incidences of grade III-IV acute GVHD (4% versus 9%, P = .14) and moderate-severe chronic GVHD (22% versus 19%, P = .28) were similar. Limitations of our study include limited sample size, differences between haplo and MSD/MUD groups and heterogeneous additional immunosuppression and PTCY timing in MSD/MUD. The use of an HLA-identical donor with PTCY in patients with AML showed lower incidence of clinically significant grade II-IV acute GVHD compared to haplo donors. Further studies with larger sample sizes should be performed to establish a possible benefit of HLA-identical donor on survival. © 2022 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Prognostic heterogeneity of adult B-cell precursor acute lymphoblastic leukaemia patients with t(1;19)(q23;p13)/TCF3-PBX1 treated with measurable residual disease-oriented protocols.

The prognosis of t(1;19)(q23;p13)/transcription factor 3-pre-B-cell leukaemia homeobox 1 (TCF3-PBX1) in adolescent and adult patients with acute lymphoblastic leukaemia (ALL) treated with measurable residual disease (MRD)-oriented trials remains controversial. In the present study, we analysed the outcome of adolescent and adult patients with t(1;19)(q23;p13) enrolled in paediatric-inspired trials. The patients with TCF3-PBX1 showed similar MRD clearance and did not have different survival compared with other B-cell precursor ALL patients. However, patients with TCF3-PBX1 had a significantly higher cumulative incidence of relapse, especially among patients aged ≥35 years carrying additional cytogenetic alterations. These patients might benefit from additional/intensified therapy (e.g. immunotherapy in first complete remission with or without subsequent haematopoietic stem cell transplantation).

Adverse prognostic impact of complex karyotype (≥3 cytogenetic alterations) in adult T-cell acute lymphoblastic leukemia (T-ALL).

The potential prognostic value of conventional karyotyping in adult T-cell acute lymphoblastic leukemia (T-ALL) remains an open question. We hypothesized that a modified cytogenetic classification, based on the number and type of cytogenetic abnormalities, would allow the identification of high-risk adult T-ALL patients. Complex karyotype defined by the presence of ≥3 cytogenetic alterations identified T-ALL patients with poor prognosis in this study. Karyotypes with ≥3 abnormalities accounted for 16 % (22/139) of all evaluable karyotypes, corresponding to the largest poor prognosis cytogenetic subgroup of T-ALL identified so far. Patients carrying karyotypes with ≥3 cytogenetic alterations showed a significantly inferior response to therapy, and a poor outcome in terms of event-free survival (EFS), overall survival (OS) and cumulative incidence of relapse (CIR), independently of other baseline characteristics and the end-induction minimal residual disease (MRD) level. Additional molecular analyses of patients carrying ≥3 cytogenetic alterations showed a unique molecular profile that could contribute to understand the underlying molecular mechanisms of resistance and to evaluate novel targeted therapies (e.g. IL7R directed) with potential impact on outcome of adult T-ALL patients.

Second allogeneic transplants for multiple myeloma: a report from the EBMT Chronic Malignancies Working Party.

The EBMT Chronic Malignancies Working Party performed a retrospective analysis of 215 patients who underwent a second allo-HCT for myeloma between 1994 and 2017, 159 for relapse and 56 for graft failure. In the relapse group, overall survival (OS) was 38% (30-46%) at 2 years and 25% (17-32%) at 5 years. Patients who had a HLA-identical sibling (HLAid-Sib) donor for their first and second transplants had superior OS (5 year OS: HLAid-Sib/HLAid-Sib: 35% (24-46%); Others 9% (0-17%), p < 0.001). There was a significantly higher incidence of acute grade II-IV GvHD in those patients who had also developed GvHD following their initial HLA-identical sibling allo-HCT (HLAid-Sib/HLAid-Sib: 50% (33-67%); Other 22% (8-36%), p = 0.03). More as opposed to fewer than 2 years between transplants was associated with superior 5-yr OS (31% (21-40%) vs. 10% (1-20%), P = 0.005). On multivariate analysis, consecutive HLA-identical sibling donor transplants conferred a significant OS advantage (0.4 (0.24-0.67), p < 0.001). In the graft failure group, OS was 41% at 2 years. In summary, a second allo-HCT using a HLA-identical sibling donor, if available, provides the best transplant outcomes for relapsed myeloma in this setting.

A randomised, placebo-controlled phase 3 study to evaluate the efficacy and safety of ASP0113, a DNA-based CMV vaccine, in seropositive allogeneic haematopoietic cell transplant recipients.

BACKGROUND: Cytomegalovirus (CMV) is a complication of allogeneic haematopoietic cell transplantation (allo-HCT). ASP0113, a DNA-based vaccine, contains two plasmids encoding human CMV glycoprotein B and phosphoprotein 65 (pp65). We assessed ASP0113 in CMV-seropositive allo-HCT recipients. METHODS: In this phase 3, randomised, placebo-controlled study, CMV-seropositive allo-HCT recipients were randomly assigned (1:1) via interactive response technology to receive five injections of 1 mL of 5 mg/mL ASP0113 or placebo. The pharmacist and designated staff were unblinded. Masked syringes maintained the blind for patients and study personnel. Efficacy and safety analyses included patients who received ≥1 dose of ASP0113/placebo. The primary efficacy endpoint was the proportion of allo-HCT recipients with composite all-cause mortality and adjudicated CMV end-organ disease (EOD) by 1 year post-transplant. ClinicalTrials.gov: NCT01877655 (not recruiting). FINDINGS: Patients were recruited between Sept 11, 2013 and Sept 21, 2016. Overall, 501 patients received ≥1 dose of ASP0113 (n = 246) or placebo (n = 255). The proportion of patients with composite all-cause mortality and adjudicated CMV EOD by 1 year post-transplant was 35.4% (n = 87) with ASP0113 and 30•2% (n = 77) with placebo (odds ratio 1.27; 95% confidence interval: 0.87 to 1.85; p = 0.205). Incidence of injection site-related treatment-emergent adverse events (TEAEs) was higher with ASP0113 than placebo. Overall incidence and severity of other TEAEs was similar between groups. T-cell response to pp65 increased over time and was greater with placebo than ASP0113 (p = 0.027). INTERPRETATION: ASP0113 did not reduce overall mortality or CMV EOD by 1 year post-transplant. Safety findings were similar between groups. FUNDING: Astellas Pharma Global Development, Inc .

Chemotherapy or allogeneic transplantation in high-risk Philadelphia chromosome-negative adult lymphoblastic leukemia.

The need for allogeneic hematopoietic stem cell transplantation (allo-HSCT) in adults with Philadelphia chromosome-negative (Ph-) acute lymphoblastic leukemia (ALL) with high-risk (HR) features and adequate measurable residual disease (MRD) clearance remains unclear. The aim of the ALL-HR-11 trial was to evaluate the outcomes of HR Ph- adult ALL patients following chemotherapy or allo-HSCT administered based on end-induction and consolidation MRD levels. Patients aged 15 to 60 years with HR-ALL in complete response (CR) and MRD levels (centrally assessed by 8-color flow cytometry) <0.1% after induction and <0.01% after early consolidation were assigned to receive delayed consolidation and maintenance therapy up to 2 years in CR. The remaining patients were allocated to allo-HSCT. CR was attained in 315/348 patients (91%), with MRD <0.1% after induction in 220/289 patients (76%). By intention-to-treat, 218 patients were assigned to chemotherapy and 106 to allo-HSCT. The 5-year (±95% confidence interval) cumulative incidence of relapse (CIR), overall survival (OS), and event-free survival probabilities for the whole series were 43% ± 7%, 49% ± 7%, and 40% ± 6%, respectively, with CIR and OS rates of 45% ± 8% and 59% ± 9% for patients assigned to chemotherapy and of 40% ± 12% and 38% ± 11% for those assigned to allo-HSCT, respectively. Our results show that avoiding allo-HSCT does not hamper the outcomes of HR Ph- adult ALL patients up to 60 years with adequate MRD response after induction and consolidation. Better postremission alternative therapies are especially needed for patients with poor MRD clearance. This trial was registered at www.clinicaltrials.gov as # NCT01540812.

Treatment of Frail Older Adults and Elderly Patients With Philadelphia Chromosome-negative Acute Lymphoblastic Leukemia: Results of a Prospective Trial With Minimal Chemotherapy.

BACKGROUND: The treatment of acute lymphoblastic leukemia (ALL) in older adults and elderly patients is a challenge, and modern protocols include targeted therapy and immunotherapy in combination with attenuated or minimal chemotherapy. However, frail patients are excluded from these trials, and reports on the outcome of this subgroup of patients are scarce. Our objective was to analyze the outcome of unfit older adults and elderly patients with Philadelphia chromosome-negative ALL included in a prospective trial (ALL-07FRAIL). PATIENTS AND METHODS: Older adults and elderly patients with Charlson Comorbidity Index (CCI) ≥ 4 were included. Induction therapy consisted of vincristine and dexamethasone, and maintenance therapy with mercaptopurine and methotrexate for 2 years. RESULTS: Seventy-two patients with a median age of 67 years (range, 57-89 years) and a median CCI of 5 (range, 4-12) were included. The rates of early withdrawal, early death, resistance, and complete response (CR) were 5%, 10%, 31%, and 54%, respectively. Six patients with CR abandoned the study, 5 died in CR, and 23 relapsed (cumulative relapse incidence 75%). The medians of disease-free and overall survival (OS) were 6.9 months (95% confidence interval [CI], 0.3-13.5 months) and 7.6 months (95% CI, 6.3-8.9 months), respectively. The most frequent toxic events were hematologic (neutropenia 77% and thrombocytopenia 54%, of grade III-IV in all cases). Eastern Cooperative Oncology Group score but not the CCI had significant impact on OS. CONCLUSION: Complete remission with very attenuated chemotherapy can be attained in one-half of older or elderly infirm patients with ALL. These results suggest that some of these patients could benefit from the concomitant or subsequent use of immunotherapy and/or targeted therapy.

Conditioning-based outcomes after allogeneic transplantation for myeloma following a prior autologous transplant (1991-2012) on behalf of EBMT CMWP.

OBJECTIVES: The aim of this study was to compare the effect of the intensity of conditioning approaches used in allogeneic transplantation in myeloma-reduced intensity conditioning (RIC), non-myeloablative (NMA), myeloablative conditioning (MAC) or Auto-AlloHCT-on outcomes in patients who had had a prior autologous transplant. METHODS: A retrospective analysis of the EBMT database (1991-2012) was performed. RESULTS: A total of 344 patients aged between 40 and 60 years at the time of alloHCT were identified: 169 RIC, 69 NMA, 65 MAC and 41 Auto-Allo transplants. At a median follow-up of 54 months, the probabilities of overall survival (OS) at 5 years were 39% (95% CI 31%-47%), 45% (95% CI 32%-57%), 19% (95% CI 6%-32%) and 34% (95% CI 17%-51%), respectively. Status at allogeneic HCT other than CR or PR conferred a 70% higher risk of death and a 40% higher risk of relapse. OS was markedly lower in the MAC group (P = .004). MAC alloHCT was associated with a higher risk of death than RIC alloHCT until 2002 (HR = 4.1, P < .001) but not after 2002 (HR = 1.2, P = .276). CONCLUSION: From 1991 to 2002, MAC was associated with poorer OS. Between 2003 and 2012, there were no significant differences in outcomes based on these different approaches.

Allogeneic stem-cell transplantation in HIV-1-infected patients with high-risk hematological disorders.

INTRODUCTION: Although a number of patients with HIV infection and hematological disease have successfully undergone allogeneic hematopoietic stem-cell transplantation (HSCT), short and long-term outcomes remain not well known. We report the largest Spanish experience treating HIV-infected adult patients with high-risk hematological malignancies with allogeneic HSCT. METHODS: We retrospectively reviewed 22 HIV-positive patients who received allogeneic HSCT in five centers in Spain. RESULTS: A total of 22 patients with high-risk hematological malignancies were transplanted between 1999 and 2018. Median age was 44 years. With a median follow-up of 65 months (8-112), overall survival and event-free survival were 46%. Nonrelapse mortality was 14% at 12 months and relapse was 24% at 24 months. Grade II-IV acute graft-versus-host disease (GVHD) rate was 44%, and moderate/severe chronic GVHD rate was 41% at 24 months. All patients received combination antiretroviral therapy. Two patients showed severe toxicity related to drug interaction with antiretroviral therapy. 68% of patients showed infectious complications with viral infections as the most frequent cause. Two patients had invasive aspergillosis and one patient presented disseminated tuberculosis. All survivors except one maintained undetectable HIV load at last follow-up after HSCT. CONCLUSION: Allogeneic HSCT is an effective therapy for high-risk hematological malignancies in patients with HIV infection, and long-term HIV suppression with combination antiretroviral therapy is feasible. However, drug interactions with antiretroviral agents, occurrence of GVHD, and frequent infectious complications account for a complex procedure in this population. Selected HIV-infected patients with hematologic malignancies should be considered for allo-HSCT when indicated, in experienced centers.

Primary and Secondary Immunodeficiency Diseases in Oncohaematology: Warning Signs, Diagnosis, and Management.

Background: Immunodeficiencies (ID), in particular primary immunodeficiencies (PID), are often associated with haematological manifestations, such as peripheral cytopenias or lymphoproliferative syndromes. Early diagnosis and management have significant prognostic implications. Secondary immunodeficiencies (SID) may also be induced by oncohaematological diseases and their treatments. Haematologists and oncologists must therefore be aware of the association between blood disorders and cancer and ID, and be prepared to offer their patients appropriate treatment without delay. Our aim was to define the warning signs of primary and secondary IDs in paediatric and adult patients with oncohaematological manifestations. Methods: A multidisciplinary group of six experts (2 haematologists, 2 immunologists, and 2 paediatricians specializing in ID) conducted a literature review and prepared a document based on agreements reached an in-person meeting. An external group of 44 IDs specialists from all over Spain assessed the document and were consulted regarding their level of agreement. Results: This document identifies the haematological and extra-haematological diseases that should prompt a suspicion of PIDs in adults and children, in both primary care and haematology and oncology departments. Cytopenia and certain lymphoproliferative disorders are key diagnostic pointers. The diagnosis must be based on a detailed clinical history, physical exploration, complete blood count and standard laboratory tests. The immunological and haematological tests included in the diagnostic process will depend on the care level. Patients who are candidates for immunoglobulin replacement therapy must be carefully selected, and treatment should be offered as soon as possible to avoid the development of complications. Finally, this document recommends procedures for monitoring these patients. Conclusions: This document combines scientific evidence with the opinion of a broad panel of experts, and emphasizes the importance of an early diagnosis and treatment to avoid complications. The resulting document is a useful tool for primary care physicians and specialists who see both adult and paediatric patients with oncohaematological diseases.

The poor prognosis of low hypodiploidy in adults with B-cell precursor acute lymphoblastic leukaemia is restricted to older adults and elderly patients.

The prognostic significance of low-hypodiploidy has not been extensively evaluated in minimal residual disease (MRD)-oriented protocols for adult acute lymphoblastic leukaemia (ALL). We analysed the outcome of hypodiploid adult ALL patients treated within Programa Español de Tratamientos en Hematología (PETHEMA) protocols. The 5-year cumulative incidence of relapse (CIR) of low-hypodiploid B-cell precursor (BCP)-ALL was significantly higher than that of high-hypodiploids (52% vs. 12%, P = 0.013). Low-hypodiploid BCP-ALL patients aged ≤35 years showed superior survival (71% vs. 21%, P = 0.026) and lower 5-year CIR (17% vs. 66%, P = 0.090) than low-hypodiploids aged >35 years. Older adults and elderly low-hypodiploid BCP-ALL patients show dismal prognosis although achieving an end-induction good MRD response.

Busulfan-based myeloablative conditioning regimens for haploidentical transplantation in high-risk acute leukemias and myelodysplastic syndromes.

BACKGROUND: High-risk acute leukemia (AL) and myelodysplastic syndrome (MDS) remain a therapeutic challenge. Unmanipulated haploidentical-related donor transplantation based on a myeloablative conditioning regimen (HAPLO-MAC) and post-transplant cyclophosphamide (PT-Cy) as prophylaxis against graft vs host disease (GvHD) is now a promising rescue strategy that could become universally available. OBJECTIVE: To evaluate the results of HAPLO-MAC with PT-Cy in patients with AL and MDS reported to the Haploidentical Transplantation Subcommittee of the Spanish Group for Hematopoietic Transplantation (GETH). PATIENTS AND METHODS: We report our multicenter experience using an IV busulfan-based HAPLO-MAC regimen and PT-Cy for treatment of 65 adults with high-risk AL and MDS. RESULTS: Engraftment was recorded in 64 patients (98.5%), with a median time to neutrophil and platelet recovery of 16 and 27 days, respectively. The cumulative incidence of grade II-IV acute GvHD and chronic GvHD was 28.6% and 27.5%, respectively. After a median follow-up of 31 months for survivors, the cumulative incidence of non-relapse mortality and relapse at 2 years was 18.8% and 25%, respectively. Estimated 30-month event-free survival and overall survival were 56% and 54.5%, respectively. CONCLUSION: HAPLO-MAC comprising an IV busulfan-based conditioning regimen enabled long-term disease control with acceptable toxicity in high-risk AL and MDS.