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Abstract: Although intensive induction chemotherapy (IC) remains the standard of care for younger patients with acute myeloid leukemia (AML), hypomethylating agents + venetoclax (HMA/VEN) can lead to durable remission among older patients with nucleophosmin 1 (NPM1) mutations. Whether IC or HMA/VEN is superior in patients aged ≥60 years with NPM1-mutant AML is unknown. We performed an international, multicenter retrospective cohort study of 221 patients (147 IC and 74 HMA/VEN) with previously untreated NPM1-mutant AML. Composite complete remission (cCR) (defined as CR + CR with incomplete count recovery) rate was similar for IC and HMA/VEN (cCR, 85% vs 74%; P = .067). Although overall survival (OS) was favorable with IC in unselected patients compared with HMA/VEN (24-month OS, 59% [95% confidence interval (CI), 52-69%] vs 38% [95% CI, 27-55%]; P = .013), it was not statistically different among patients aged 60-75 years (60% [95% CI, 52-70%] vs 44% [95% CI, 29-66%]; P = .069) and patients who received an allogeneic stem cell transplant (70% [95% CI, 58-85%] vs 66% [95% CI, 44-100%]; P = .56). Subgroup analyses suggested that patients with normal cytogenetics (24-month OS, 65% [95% CI, 56-74%] with IC vs 40% [95% CI, 26-60%] with HMA/VEN; P = .009) and without FLT3 internal tandem duplication mutations might benefit from IC compared with HMA/VEN (24-month OS, 68% [95% CI, 59-79%] vs 43% [95% CI, 29-63%]; P = .008). In multivariable analysis, OS was not statistically different between patients treated with IC and HMA/VEN (hazard ratio for death with HMA/VEN vs IC, 0.71; 95% CI, 0.40-1.27; P = .25)., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

We conducted a retrospective analysis of WT1- mutated acute myeloid leukemia (AML) patients who underwent allogeneic stem cell transplant. Thirty-seven patients with WT1- mutated AML were identified. Primary induction failure (40%) and early relapse rate (18%) after idarubicin/cytarabine (7 + 3) chemotherapy were observed. All patients with induction failure subsequently achieved CR with additional chemotherapy. There was no significant difference between outcomes after myeloablative vs. reduced intensity (Fludarabine/Melphalan [Flu/Mel]) conditioning regimens. RFS but not OS was significantly better in patients who received FLAG-IDA prior to transplant and/or a fludarabine-containing conditioning. In an independent ex vivo study, WT1 -mutated AML samples exhibited greater sensitivity to fludarabine ( p  = 0.026) and melphalan ( p  = 0.0005) than non- WT1- mutated AML samples while there was no difference between sensitivity to cytarabine. Our data favor using a fludarabine-based induction for AML with WT1 mutation instead of 7 + 3. Fludarabine conditioning regimens for alloHCT showed better RFS but not OS.

Targeting critical epigenetic regulators reverses aberrant transcription in cancer, thereby restoring normal tissue function 1-3 . The interaction of menin with lysine methyltransferase 2A (KMT2A), an epigenetic regulator, is a dependence in acute leukaemia caused by either rearrangement of KMT2A or mutation of the nucleophosmin 1 gene (NPM1) 4-6 . KMT2A rearrangements occur in up to 10% of acute leukaemias and have an adverse prognosis, whereas NPM1 mutations occur in up to 30%, forming the most common genetic alteration in acute myeloid leukaemia 7,8 . Here, we describe the results of the first-in-human phase 1 clinical trial investigating revumenib (SNDX-5613), a potent and selective oral inhibitor of the menin-KMT2A interaction, in patients with relapsed or refractory acute leukaemia (ClinicalTrials.gov, NCT04065399). We show that therapy with revumenib was associated with a low frequency of grade 3 or higher treatment-related adverse events and a 30% rate of complete remission or complete remission with partial haematologic recovery (CR/CRh) in the efficacy analysis population. Asymptomatic prolongation of the QT interval on electrocardiography was identified as the only dose-limiting toxicity. Remissions occurred in leukaemias refractory to multiple previous lines of therapy. We demonstrate clearance of residual disease using sensitive clinical assays and identify hallmarks of differentiation into normal haematopoietic cells, including differentiation syndrome. These data establish menin inhibition as a therapeutic strategy for susceptible acute leukaemia subtypes., (© 2023. The Author(s).)

FLT3, IDH1 and IDH2 inhibitors as well as venetoclax in combination with hypomethylating agents or low-dose cytarabine have expanded treatment options for patients with acute myeloid leukemia (AML). However, little data exist on the efficacy of venetoclax-based therapies in AML patients previously treated with FLT3 or IDH1/2 inhibitors. In this multicenter, retrospective cohort study, we included 44 patients who received venetoclax-based therapy after FLT3, IDH1 or IDH2 inhibitors. The overall response rate (ORR; composite of complete remission [CR]/CR with incomplete count recovery, partial remission, and morphologic leukemia free state) was 56.8% (18.2% CR) and a median overall survival of 9.2 months. While 6 out of 7 patients with IDH1 mutations who had previously been treated with ivosidenib responded to venetoclax-based therapy, FLT3- ITD mutations were associated with a lower response rate. Our data suggest that venetoclax can be an effective salvage therapy in patients previously treated with IDH1/2 or FLT3 inhibitors.

Small molecule inhibitors targeting mutant FLT3, IDH1, and IDH2 as well as venetoclax-based combination therapies have expanded treatment options for patients with acute myeloid leukemia (AML). As the landmark trials leading to the approval of FLT3, IDH1, and IDH2 inhibitors in R/R-AML were conducted prior to the widespread use of venetoclax, it is unclear how these results apply in the current era of venetoclax based therapy frequently being used in the frontline treatment of AML. In this multicenter, retrospective cohort study, we included 53 patients who received FLT3, IDH1 or IDH2 inhibitors after disease progression on venetoclax-based therapy. Among patients treated with targeted agents after venetoclax, the overall response rate (ORR; composite of complete remission [CR]/CR with incomplete count recovery, partial remission, and morphologic leukemia free state) was 17.7 % (n = 9 patients) and median OS of 4.2 months. Eight of 9 patients responding to targeted agents after venetoclax received gilteritinib. None of the patients with RAS pathway mutations responded to targeted agents after venetoclax. Additionally, mutations in TP53 and KRAS were associated with shorter OS among patients treated targeted agents. Our data suggest that response rates to targeted therapies after venetoclax are low and novel therapeutic strategies are warranted., Competing Interests: Conflict of Interest R.M.S. participated in advisory boards, and/or had a consultancy with and received honoraria from Bristol Myers Squibb and Gilead Sciences, Inc; divested equity interest in Curis Oncology. A.D.G. received research funding from Celularity, ADC Therapeutics, Aprea, AROG, Pfizer, Prelude, and Trillium; received research funding from and served as a consultant for Aptose and Daiichi Sankyo; served as a consultant and member of advisory committees for Astellas, Celgene, and Genentech; received research funding from, served as a consultant for, and was a member of advisory committees for AbbVie; and received honoraria from Dava Oncology. A.M.Z. received research funding (institutional) from Celgene/BMS, Abbvie, Astex, Pfizer, Medimmune/AstraZeneca, Boehringer-Ingelheim, Trovagene/Cardiff oncology, Incyte, Takeda, Novartis, Aprea, and ADC Therapeutics. A.M.Z. participated in advisory boards, and/or had a consultancy with and received honoraria from AbbVie, Otsuka, Pfizer, Celgene/BMS, Jazz, Incyte, Agios, Boehringer-Ingelheim, Novartis, Acceleron, Astellas, Daiichi Sankyo, Cardinal Health, Taiho, Seattle Genetics, BeyondSpring, Cardiff Oncology, Takeda, Ionis, Amgen, Janssen, Epizyme, Syndax, Gilead, Kura, Chiesi, ALX Oncology, BioCryst, and Tyme. A.M.Z. served on clinical trial committees for Novartis, Abbvie, Geron and Celgene/BMS. A.M.Z. received travel support for meetings from Pfizer, Novartis, and Cardiff Oncology. E.M.S. received research funding from Bayer; was a consultant for Amgen, AbbVie, Seattle Genetics, and Biotheryx; served as a consultant and received research funding from Syndax; was a member of the Board of Directors or advisory committee for PTC Therapeutics and Syros; served as a consultant and was member of the Board of Directors or advisory committee for Astellas Pharmaceutical, Agios Pharmaceuticals, and Genentech; served as a consultant, received research funding, and was a member of the Board of Directors or advisory committee for Daiichi-Sankyo, Celgene Pharmaceuticals, and Novartis; and is a current equity holder in privately held Auron Therapeutics. G.M. received research funding from Merck, served on the scientific board for BMS, and Abbvie, and participated as a speaker for Abbvie. A.S. served on the speakers bureau for Amgen. D.J.D. had a consultancy with Abbvie Amgen, Autolus, Blueprint, Forty-Seven, Glycomimetrics, Inctye, Jazz, Kite, Novartis, Pfizer, Servier, and Takeda. D.J.D. received grant/research funding Abbvie, Novartis, Blueprint, Glycomimetrics. R.M.S. received personal fees from Abbvie, Actinium, Agios, Astellas, Biolinerx, Celgene, Daiichi-Sankyo, Elevate, Gemoab, Janssen, Jazz, Macrogenics, Novartis, OncoNova, Syndax, Syntrix, Syros, Takeda, Trovagene, BerGenBio, Foghorn Therapeutics, GlaxoSmith Kline, Aprea, Innate, Amgen, BMS, Boston Pharmaceuticals, Kura Oncology, and Epizyme. R.M.S. received grant funding from Abbvie, Agios, Arog, and Novartis. IA serves on advisory boards for Amgen, Kite pharmaceuticals, AbbVie, JAZZ and Agios Pharmaceuticals, and is a consultant for Pfizer, Autolus Therapeutics and Amgen, and received research support by MacroGenics and Abbvie. B.J.B. served on the advisory board for Oncovalent. MS is a member of the advisory board for Novartis and is consulting for Curis Oncology, Haymarket Media and Boston Consulting., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background/aim: The therapeutic potential of bromodomain and extra-terminal motif (BET) inhibitors in hematological cancers has been well established in preclinical and early-stage clinical trials, although as of yet, no BETtargeting agent has achieved approval. To add insight into potential response to mivebresib (ABBV-075), a broadspectrum BET inhibitor, co-clinical modeling of individual patient biopsies was conducted in the context of a Phase I trial in acute myeloid leukemia (AML)., Materials and Methods: Co-clinical modeling involves taking the patient's biopsy and implanting it in mice with limited passage so that it closely retains the original characteristics of the malignancy and allows comparisons of response between animal model and clinical data. Procedures were developed, initially with neonate NOD/Shi-scid-IL2rγnull (NOG) mice and then optimized with juvenile NOG-EXL as host mice, eventually resulting in a robust rate of engraftment (16 out of 26, 62%)., Results: Results from the co-clinical AML patient-derived xenograft (PDX) modeling (6 with >60% inhibition of bone marrow blasts) were consistent with the equivalent clinical data from patients receiving mivebresib in monotherapy, and in combination with venetoclax. The modeling system also demonstrated the activity of a novel BD2-selective BET inhibitor (ABBV-744) in the preclinical AML setting. Both agents were also highly effective in inhibiting blast counts in the spleen (10/10 and 5/6 models, respectively)., Conclusion: These findings confirm the validity of the model system in the co-clinical setting, establish highly relevant in vivo models for the discovery of cancer therapy, and indicate the therapeutic value of BET inhibitors for AML and, potentially, myelofibrosis treatment., (Copyright © 2022, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Graft-versus-host disease (GVHD) has remained the main cause of post-transplantation mortality and morbidity after allogeneic hematopoietic cell transplantation (alloHCT), adding significant economic burden and affecting quality of life. It would be desirable to reduce the rate of GVHD among patients in complete remission (CR) without increasing the risk of relapse. In this study, we have tested a novel conditioning regimen of total marrow and lymphoid irradiation (TMLI) at 2000 cGy, together with post-transplantation cyclophosphamide (PTCy) for patients with acute myeloid leukemia in first or second CR, to attenuate the risk of chronic GVHD by using PTCy, while using escalated targeted radiation conditioning before allografting to offset the possible increased risk of relapse. The primary objective was to evaluate the safety/feasibility of combining a TMLI transplantation conditioning regimen with a PTCy-based GVHD prophylaxis strategy, through the assessment of adverse events in terms of type, frequency, severity, attribution, time course, duration, and complications, including acute GVHD, infection, and delayed neutrophil/platelet engraftment. Secondary objectives included estimation of non-relapse mortality (NRM), overall survival (OS), relapse-free survival, acute and chronic GVHD, and GVHD-relapse-free survival (GRFS). A patient safety lead-in was first conducted to ensure there were no unexpected toxicities and was expanded on the basis of lack of dose-limiting toxicities. The patient safety lead-in segment followed 3 + 3 dose expansion/(de-)escalation rules based on observed toxicity through day 30; the starting dose of TMLI was 2000 cGy, and a de-escalation to 1800 cGy was considered. After the safety lead-in segment, an expansion cohort of up to 12 additional patients was to be studied. TMLI was administered on days -4 to 0, delivered in 200 cGy fractions twice daily. The radiation dose delivered to the liver and brain was kept at 1200 cGy. Cyclophosphamide was given on days 3 and 4 after alloHCT, 50 mg/kg each day for GVHD prevention; tacrolimus was given until day 90 and then tapered. Among 18 patients with a median age of 40 years (range 19-56), the highest grade toxicities were grade 2 Bearman bladder toxicity and stomatitis. No grade 3 or 4 Bearman toxicities or toxicity-related deaths were observed. The cumulative incidence of acute GVHD grade 2 to 4 and moderate-to-severe chronic GVHD were 11.1% and 11.9%, respectively. At a median follow up of 24.5 months, two-year estimates of OS and relapse-free survival were 86.7% and 83.3%, respectively. Disease relapse at 2 years was 16.7%. The estimates of NRM at 2 years was 0%. The GVHD/GRFS rate at 2 years was 59.3% (95% confidence interval, 28.8-80.3). This chemotherapy-free conditioning regimen, together with PTCy and tacrolimus, is safe, with no NRM. Preliminary results suggest an improved GRFS rate., (Copyright © 2022 The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Patients with acute leukemia who undergo allogenic hematopoietic cell transplantation with active disease have high rates of relapse and poor overall survival (OS) post-transplant compared to patients undergoing HCT in remission. Here, we report the long-term outcomes in 32 patients who received a high-intensity conditioning regimen comprising fractionated total body irradiation (FTBI; 1200 cGy) with pharmacokinetic (PK) dosing of intravenous Busulfan (IV BU) targeted to first dose area under curve (AUC) of 700-900 µM/min and etoposide (30 mg/kg) in a prospective phase 2 clinical trial. The median age of the patients at the time of HCT was 37 years (range: 18-50) presenting with high-risk ( n  = 6) and relapsed/refractory(r/r) acute leukemias ( n  = 26). All but one patient underwent HCT using peripheral blood stem cells from matched sibling donors. At a median follow-up of 17.3 years (range 14.4-19.0), 11 patients remained alive. The disease-free survival and OS at 15 years was 34% (versus 40% at 5-years post-HCT). The 15-year cumulative incidence of relapse was 26% and non-relapse mortality (NRM) was 38% (95% CI: 21-54%) and the cumulative incidence of chronic GVHD at 15 years was 33% using a prophylactic regimen of cyclosporine A and mycophenolate mofetil. The most common life-threatening late effects were secondary malignancies, metabolic, or cardiac complications with a cumulative incidence of 6.6%, 6.6%, and 13.3%, respectively. No unusual late effects or patterns of relapse were noted on longer followed on patients treated with intensified myeloablative condition regimen. Results from this study supports continued development of intensive conditioning regimens in patients with r/r acute leukemias to improve leukemia free (LFS) and OS in this high-risk population.

Background: Acute myeloid leukemia (AML) is a heterogenous malignancy driven by genetic and epigenetic factors. Inhibition of bromodomain and extraterminal (BET) proteins, epigenetic readers that play pivotal roles in the regulation of genes relevant to cancer pathogenesis, constitutes a novel AML treatment approach., Methods: In this first-in-human study of the pan-BET inhibitor mivebresib as monotherapy (MIV-mono) or in combination with venetoclax (MIV-Ven), the safety profile, efficacy, and pharmacodynamics of mivebresib were determined in patients with relapsed/refractory AML (ClinicalTrials.gov identifier NCT02391480). Mivebresib was administered at 3 monotherapy dose levels (1.5, 2.0, or 2.5 mg) or in combination with venetoclax (400 or 800 mg)., Results: Forty-four patients started treatment: of 19 who started MIV-mono, 5 went on to receive MIV-Ven combination therapy after disease progression and a washout period. Twenty-five patients started MIV-Ven, resulting in a total of 30 patients treated with the combination. The most common mivebresib-related treatment-emergent adverse events were dysgeusia (74%), decreased appetite (42%), and diarrhea (42%) in the MIV-mono group and decreased appetite (44%), vomiting (44%), and nausea (40%) in the MIV-Ven group. Serious adverse events occurred in 14 patients (74%) who received MIV-mono and in 22 patients (88%) who received MIV-Ven. In the MIV-mono group, responses were complete remission with incomplete blood count recovery in 1 patient and resistant disease in 15 patients. In the MIV-Ven group, responses were complete remission in 2 patients, partial remission in 2 patients, morphologic leukemia-free state in 2 patients, resistant disease in 12 patients, and aplasia in 1 patient. The pharmacodynamic effects of mivebresib were proportional to dose and drug exposure., Conclusions: Mivebresib was tolerated and showed antileukemic effects as monotherapy and in combination with venetoclax in patients with relapsed/refractory AML., Lay Summary: Mivebresib is a novel drug that influences the way cancer cells read genetic information. Mivebresib was tested together with venetoclax in patients with acute myeloid leukemia after standard medicines failed and the disease returned, or when standard medicine was unavailable. Adverse effects were described for different drug doses, and the dose that is tolerable was determined. In some patients, their leukemia improved for some time. More studies are necessary to determine whether mivebresib can be used to treat acute myeloid leukemia., (© 2021 The Authors. Cancer published by Wiley Periodicals LLC on behalf of American Cancer Society.)

Approximately 50% of acute myeloid leukemia (AML) patients do not respond to induction therapy (primary induction failure [PIF]) or relapse after <6 months (early relapse [ER]). We have recently shown an association between an immune-infiltrated tumor microenvironment (TME) and resistance to cytarabine-based chemotherapy but responsiveness to flotetuzumab, a bispecific DART antibody-based molecule to CD3ε and CD123. This paper reports the results of a multicenter, open-label, phase 1/2 study of flotetuzumab in 88 adults with relapsed/refractory AML: 42 in a dose-finding segment and 46 at the recommended phase 2 dose (RP2D) of 500 ng/kg per day. The most frequent adverse events were infusion-related reactions (IRRs)/cytokine release syndrome (CRS), largely grade 1-2. Stepwise dosing during week 1, pretreatment dexamethasone, prompt use of tocilizumab, and temporary dose reductions/interruptions successfully prevented severe IRR/CRS. Clinical benefit accrued to PIF/ER patients showing an immune-infiltrated TME. Among 30 PIF/ER patients treated at the RP2D, the complete remission (CR)/CR with partial hematological recovery (CRh) rate was 26.7%, with an overall response rate (CR/CRh/CR with incomplete hematological recovery) of 30.0%. In PIF/ER patients who achieved CR/CRh, median overall survival was 10.2 months (range, 1.87-27.27), with 6- and 12-month survival rates of 75% (95% confidence interval [CI], 0.450-1.05) and 50% (95% CI, 0.154-0.846). Bone marrow transcriptomic analysis showed that a parsimonious 10-gene signature predicted CRs to flotetuzumab (area under the receiver operating characteristic curve = 0.904 vs 0.672 for the European LeukemiaNet classifier). Flotetuzumab represents an innovative experimental approach associated with acceptable safety and encouraging evidence of activity in PIF/ER patients. This trial was registered at www.clinicaltrials.gov as #NCT02152956., (© 2021 by The American Society of Hematology.)

The combination of hypomethylating agents with the selective Bcl-2 inhibitor venetoclax (HMA-VEN) has emerged as a highly active regimen in patients with acute myelogenous leukemia (AML) in both the upfront and relapsed/refractory (r/r) settings. We report our early experience with a cohort of patients who were able to proceed to allogeneic hematopoietic cell transplantation (alloHCT) after HMA-VEN therapy. Thirty-two patients with AML (19 r/r and 13 de novo) with a median age of 62 years underwent alloHCT after HMA-VEN therapy. Twenty-two (68.8%) were in complete remission (CR)/CR with incomplete count recovery at time of HCT. With a median follow up of 14.4 months, the 1-year overall survival (OS) was 62.5%, and disease-free survival was 43.8%. The 1-year nonrelapse mortality rate was 18.8%, and the cumulative incidence of relapse was 37.5%. Among patients who underwent alloHCT in CR, the 1-year OS was 77.3%, and the cumulative incidence of nonrelapse mortality was 9.1%. The cumulative incidence of grade II-IV acute graft-versus-host disease was 43.8%. We conclude that alloHCT after HMA-VEN is therapy associated with favorable allogeneic HCT outcomes in newly diagnosed older patients with AML, as well as those with r/r AML., (Copyright © 2020 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Somatic TP53 mutations and 17p deletions with genomic loss of TP53 occur in 37% to 46% of acute myeloid leukemia (AML) with adverse-risk cytogenetics and correlate with primary induction failure, high risk of relapse, and dismal prognosis. Herein, we aimed to characterize the immune landscape of TP53-mutated AML and determine whether TP53 abnormalities identify a patient subgroup that may benefit from immunotherapy with flotetuzumab, an investigational CD123 × CD3 bispecific dual-affinity retargeting antibody (DART) molecule. The NanoString PanCancer IO360 assay was used to profile 64 diagnostic bone marrow (BM) samples from patients with TP53-mutated (n = 42) and TP53-wild-type (TP53-WT) AML (n = 22) and 45 BM samples from patients who received flotetuzumab for relapsed/refractory (R/R) AML (15 cases with TP53 mutations and/or 17p deletion). The comparison between TP53-mutated and TP53-WT primary BM samples showed higher expression of IFNG, FOXP3, immune checkpoints, markers of immune senescence, and phosphatidylinositol 3-kinase-Akt and NF-κB signaling intermediates in the former cohort and allowed the discovery of a 34-gene immune classifier prognostic for survival in independent validation series. Finally, 7 out of 15 patients (47%) with R/R AML and TP53 abnormalities showed complete responses to flotetuzumab (<5% BM blasts) on the CP-MGD006-01 clinical trial (NCT #02152956) and had significantly higher tumor inflammation signature, FOXP3, CD8, inflammatory chemokine, and PD1 gene expression scores at baseline compared with nonresponders. Patients with TP53 abnormalities who achieved a complete response experienced prolonged survival (median, 10.3 months; range, 3.3-21.3 months). These results encourage further study of flotetuzumab immunotherapy in patients with TP53-mutated AML., (© 2020 by The American Society of Hematology.)

The IL-3 alpha chain receptor (CD123) is a cell surface protein that is widely expressed by various subtypes of acute leukemia, including acute myeloid leukemia (AML), acute lymphoblastic leukemia and blastic plasmacytoid dendritic cell neoplasm. Notably, CD123 is preferentially overexpressed in leukemia stem cells (LSC) in contrast to normal hematopoietic stem cells, and this differential expression allows for the selective eradication of LSC and leukemic blasts through therapeutic targeting of CD123, with less impact on hematopoietic cells. The level of CD123 expression in AML correlates with both treatment response and outcomes. Therefore, targeting CD123 represents a promising universal therapeutic target in advanced acute leukemias irrespective of the individual leukemia phenotype. There are currently 31 ongoing clinical trials examining the utility of CD123-based targeted therapies. Here we focus our review on current efforts to target CD123 in acute leukemia through various therapeutic constructs.

Cytogenetic risk stratification at diagnosis has long been one of the most useful tools to assess prognosis in acute lymphoblastic leukemia (ALL). To examine the prognostic impact of cytogenetic abnormalities on outcomes after allogeneic hematopoietic cell transplantation, we studied 1731 adults with Philadelphia-negative ALL in complete remission who underwent myeloablative or reduced intensity/non-myeloablative conditioning transplant from unrelated or matched sibling donors reported to the Center for International Blood and Marrow Transplant Research. A total of 632 patients had abnormal conventional metaphase cytogenetics. The leukemia-free survival and overall survival rates at 5 years after transplantation in patients with abnormal cytogenetics were 40% and 42%, respectively, which were similar to those in patients with a normal karyotype. Of the previously established cytogenetic risk classifications, modified Medical Research Council-Eastern Cooperative Oncology Group score was the only independent prognosticator of leukemia-free survival ( P =0.03). In the multivariable analysis, monosomy 7 predicted post-transplant relapse [hazard ratio (HR)=2.11; 95% confidence interval (95% CI): 1.04-4.27] and treatment failure (HR=1.97; 95% CI: 1.20-3.24). Complex karyotype was prognostic for relapse (HR=1.69; 95% CI: 1.06-2.69), whereas t(8;14) predicted treatment failure (HR=2.85; 95% CI: 1.35-6.02) and overall mortality (HR=3.03; 95% CI: 1.44-6.41). This large study suggested a novel transplant-specific cytogenetic scheme with adverse [monosomy 7, complex karyotype, del(7q), t(8;14), t(11;19), del(11q), tetraploidy/near triploidy], intermediate (normal karyotype and all other abnormalities), and favorable (high hyperdiploidy) risks to prognosticate leukemia-free survival ( P =0.02). Although some previously established high-risk Philadelphia-negative cytogenetic abnormalities in ALL can be overcome by transplantation, monosomy 7, complex karyotype, and t(8;14) continue to pose significant risks and yield inferior outcomes., (Copyright© 2020 Ferrata Storti Foundation.)

Cyclophosphamide (Cy)/etoposide combined with fractionated total body irradiation (FTBI) or i.v. busulfan (Bu) has been the main conditioning regimens for allogeneic hematopoietic cell transplantation (alloHCT) for young patients with acute myelogenous leukemia (AML) eligible for a myeloablative conditioning (MAC) regimen. Recent data has suggested that i.v. Bu could be the preferred myeloablative regimen in patients with myeloid malignancies. However, Bu-based regimens are associated with higher rates of sinusoidal obstruction syndrome. Here we report long-term survival outcomes of patients with AML receiving FTBI combined with Cy or etoposide before undergoing alloHCT at City of Hope (COH). We obtained a retrospective review of a prospectively maintained institutional registry of clinical outcomes in 167 patients (median age, 41 years; range, 18 to 57 years) with AML in first or second complete remission who underwent alloHCT at COH between 2005 and 2015. Eligible patients received a MAC regimen with FTBI (1320 cGy) and Cy (120 mg/kg) for unrelated donor transplantation or etoposide (60 mg/kg) for related donor transplantation. Graft-versus-host disease (GVHD) prophylaxis was provided with tacrolimus and sirolimus. In this retrospective study, 6-year overall survival was 60% and nonrelapse mortality was 15%. The GRFS rate was 45% at 1 year and 39% at 2 years. We also describe late metabolic effects and report the cumulative incidence of secondary malignancies (9.5%). Overall, in this young adult patient population, our results compare favorably to chemotherapy-based (i.v. Bu) conditioning regimens without significant long-term toxicity arising from TBI-based regimens., (Copyright © 2019 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

The E3 ligase human double minute 2 (HDM2) regulates the activity of the tumor suppressor protein p53. A p53-independent HDM2 expression has been reported on the membrane of cancer cells but not on that of normal cells. Herein, we first showed that membrane HDM2 (mHDM2) is exclusively expressed on human and mouse AML blasts, including leukemia stem cell (LSC)-enriched subpopulations, but not on normal hematopoietic stem cells (HSCs). Higher mHDM2 levels in AML blasts were associated with leukemia-initiating capacity, quiescence, and chemoresistance. We also showed that a synthetic peptide PNC-27 binds to mHDM2 and enhances the interaction of mHDM2 and E-cadherin on the cell membrane; in turn, E-cadherin ubiquitination and degradation lead to membrane damage and cell death of AML blasts by necrobiosis. PNC-27 treatment in vivo resulted in a significant killing of both AML "bulk" blasts and LSCs, as demonstrated respectively in primary and secondary transplant experiments, using both human and murine AML models. Notably, PNC-27 spares normal HSC activity, as demonstrated in primary and secondary BM transplant experiments of wild-type mice. We concluded that mHDM2 represents a novel and unique therapeutic target, and targeting mHDM2 using PNC-27 selectively kills AML cells, including LSCs, with minimal off-target hematopoietic toxicity.

The combination of venetoclax with hypomethylating agents (VEN-HMAs) showed promising activity in newly diagnosed and relapsed/refractory (r/r) acute myeloid leukemia (AML). Treatment with VEN-HMAs results in prolonged cytopenia, thereby exposing patients to invasive fungal infections (IFIs). Here, we retrospectively studied a cohort of 119 AML patients treated with VEN-HMAs and analyzed the occurrence of IFIs, as well as our practice of antifungal prophylaxis, with the aim to identify the nature and risk factors for IFIs and their association with the type of antifungal prophylaxis used. The intended antifungal prophylaxis was micafungin in 38% of patients, azoles in 41% of patients, and none in 21% of patients. Older age was associated with no antifungal prophylaxis or micafungin use and lesser use of azoles (P = .043). We recorded 15 (12.6%) patients who developed probable or proven IFIs, with a median onset of 72 days (range, 35-281) after starting therapy. IFIs were more common among nonresponders compared with responders to VEN-HMA therapy (22% vs 6%, P = .0132) and in r/r compared with newly diagnosed AML (19% vs 5%, P = .0498); however, the antifungal prophylaxis used, patient age, hypomethylating agent schedule, history of prior allogeneic transplant, and initial neutropenia duration did not influence the development of IFIs during therapy. We conclude that the overall risk of IFIs during VEN-HMA therapy is low. The risk of IFIs is higher in nonresponders and in those who were treated in the r/r setting; these patients need reevaluation of their antifungal prophylaxis to minimize the risk of IFIs during therapy., (© 2019 by The American Society of Hematology.)

Induction of reactive oxygen species (ROS), an important process for the cytotoxicity of various acute myeloid leukemia (AML) therapies including hypomethylating agents (HMAs), concurrently activates the NF-E2-related factor 2 (Nrf2) antioxidant response pathway which in turn results in induction of antioxidant enzymes that neutralize ROS. In this study, we demonstrated that Nrf2 inhibition is an additional mechanism responsible for the marked antileukemic activity in AML seen with the combination of HMAs and venetoclax (ABT-199). HMA and venetoclax combined treatment augmented mitochondrial ROS induction and apoptosis compared with treatment HMA alone. Treatment of AML cell lines as well as primary AML cells with venetoclax disrupted HMA decitabine-increased nuclear translocation of Nrf2 and induction of downstream antioxidant enzymes including heme oxygenase-1 and NADP-quinone oxidoreductase-1. Venetoclax treatment also leads to dissociation of B-cell lymphoma 2 from the Nrf2/Keap-1 complex and targets Nrf2 to ubiquitination and proteasomal degradation. Thus, our results here demonstrated an undiscovered mechanism underlying synergistic effect of decitabine and venetoclax in AML cells, elucidating for impressive results in antileukemic activity against AML in preclinical and early clinical studies by combined treatment of these drugs., (© 2019 Wiley Periodicals, Inc.)

Background: Mutations in isocitrate dehydrogenase (IDH)1/2 genes result in nicotinamide adenine dinucleotide phosphate-dependent reduction of α-ketoglutarate and formation of 2-hydroxyglutarate, which blocks normal cellular differentiation and promotes leukemogenesis. Nearly 20% of acute myeloid leukemia (AML) patients carry IDH1/2 mutations. Although multiple investigators have described the prognostic implications of IDH mutations in AML patients receiving chemotherapy, the effect of these mutations on outcomes after allogeneic (allo) hematopoietic cell transplantation (HCT) is unknown., Patients and Methods: We report on the clinical outcome of a cohort of AML patients, who were tested for IDH mutations and underwent alloHCT at City of Hope (2015-2017). Of a total of 317 screened patients, 99 (31%) underwent alloHCT, of whom 23 carried and 76 did not carry IDH mutations (control)., Results: No statistical significance was detected in patient's overall survival (P = .84). With a median follow-up of 7.8 months, 1-year relapse rate of 29% and 13% was seen in the IDH-mutated and control group, respectively (P = .033). IDH1/2 mutation status remained significantly associated with relapse (hazard ratio, 2.8; P = .046) after inclusion of pre-HCT disease status in a multivariable model., Conclusion: Our results, despite low patient numbers, indicate that IDH mutations are associated with higher relapse rate after alloHCT. Further prospective studies on post transplantation IDH inhibition is required to improve outcomes in AML patients who carry IDH mutations., (Copyright © 2019. Published by Elsevier Inc.)

One of the most promising developments in therapy for acute myeloid leukemia (AML) in recent years has been the combination of hypomethylating agents (HMA, either decitabine or 5-azacytidine) with the Bcl-2 inhibitor venetoclax (VEN). Although both classes of drugs have single-agent activity in AML, the combination has resulted in high rates of complete remission (CR) both in the frontline and relapsed settings suggesting synergy between these two agents. Recent data have suggested that CR + CR with incomplete count recovery rate may exceed 70% for frontline VEN-HMA. Moreover, this activity has been observed across various genetic subtypes of AML including those known to have very poor response to conventional chemotherapy. Although VEN has only recently obtained FDA approval for treatment of AML, there has been increasing on and off-label use of this combination given its striking efficacy and excellent toxicity profile. In this article, we summarize the current available data on this combination and offer practical guidelines for management of patients receiving VEN-HMA. Our recommendations are based on protocol guidelines, published data from clinical trials as well as from analysis of real world evidence from patients treated with this combination., (© 2018 Wiley Periodicals, Inc.)

Early assessment of disease response to induction chemotherapy is important in acute myeloid leukemia (AML) in order to plan future therapy and identify chemorefractory disease. Such assessment is customarily performed by examining the bone marrow at around day 14 after initiation of chemotherapy. However, criteria for assessment of residual leukemia in day 14 bone marrow specimens as well as the significance of partial response on long term outcomes remain unclear. Clinical practices vary regarding the therapeutic intervention for residual disease and include readministration of the original induction therapy or use of a different reinduction regimen. In this article, we critically examine the prognostic significance of residual disease detected on interim bone marrow examination as well as data on reinduction therapy with the original induction regimen versus an alternate regimen. We emphasize the need for standardizing reporting of interim bone marrow assessment as well as evaluating new technologies and biomarkers for early assessment of disease response and chemosensitivity in AML., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

We retrospectively reviewed the outcome of 20 consecutive subjects with refractory/relapsed acute myeloid leukemia (AML; 9 refractory and 11 relapsed) treated at our institution with a fludarabine, cytarabine and etoposide (FCE) salvage regimen. Of 20 patients with refractory/relapsed AML, 15 (75%) achieved complete remission (CR)/CR with incomplete peripheral blood count recovery (CRi), including 14 CR and 1 CRi. The 4- and 8-week treatment-related mortality (TRM) for all patients during reinduction was 0 and 5%, respectively. Eight of 15 patients (53%) who successfully achieved CR were able to undergo allogeneic hematopoietic stem cell transplantation with a 0% non-relapse mortality rate. FCE is a new, well-tolerated, anthracycline-free regimen, which has a promising activity in relapsed/refractory AML and is associated with low TRM in this high-risk population.

Therapy-related acute myeloid leukemia (t-AML) is occasionally associated with favorable risk cytogenetics including core binding factor AML and acute promyelocytic leukemia (APL). It is unclear if these leukemias have the same favorable outcomes as their de novo counterparts. Interpretation of published data is difficult due to lack of data on the contribution of the original neoplasm as well as its treatment to overall mortality. Based on available evidence, we conclude that t-AML with favorable risk cytogenetics have superior outcomes among t-AMLs and should be treated similar to de novo AML in patients who are candidates for definitive therapy. Therapy-related APL has similar outcome as de novo APL. There is no evidence at the present time to support the routine use of allogeneic HSCT in first complete remission in t-AML with favorable cytogenetics., (Copyright © 2012 Elsevier Ltd. All rights reserved.)