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Duncan BB, Lotter JL, Superata J, Barranta ME, Machado T, Darden I, Venugopal S, Wu CO, Abkowitz JL, Dunbar CE, Young DJ. Treatment of refractory/relapsed Diamond-Blackfan anaemia with eltrombopag. Br J Haematol 2024; 204:2077-2085. [PMID: 38462764 PMCID: PMC11212774 DOI: 10.1111/bjh.19357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Accepted: 02/13/2024] [Indexed: 03/12/2024]
Abstract
Diamond-Blackfan anaemia (DBA) is a rare, inherited bone marrow failure syndrome with a ribosomal defect causing slowed globin chain production with normal haem synthesis, causing an overabundance of reactive iron/haem and erythroid-specific cellular toxicity. Eltrombopag, a non-peptide thrombopoietin receptor agonist, is a potent intracellular iron chelator and induced a robust durable response in an RPS19-mutated DBA patient on another trial. We hypothesized eltrombopag would improve RBC production in DBA patients. We conducted a single-centre, single-arm pilot study (NCT04269889) assessing safety and erythroid response of 6 months of daily, fixed-dose eltrombopag for DBA patients. Fifteen transfusion-dependent (every 3-5 weeks) patients (median age 18 [range 2-56]) were treated. One responder had sustained haemoglobin improvement and >50% reduction in RBC transfusion frequency. Of note, 7/15 (41%) patients required dose reductions or sustained discontinuation of eltrombopag due to asymptomatic thrombocytosis. Despite the low response rate, eltrombopag has now improved erythropoiesis in several patients with DBA with a favourable safety profile. Dosing restrictions due to thrombocytosis may cause insufficient iron chelation to decrease haem production and improve anaemia in most patients. Future work will focus on erythropoiesis dynamics in patients and use of haem synthesis inhibitors without an impact on other haematopoietic lineages.
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Affiliation(s)
- Brynn B Duncan
- Translational Stem Cell Biology Branch, NHLBI, Bethesda, Maryland, USA
| | | | | | | | - Tania Machado
- Office of the Clinical Director, NHLBI, Bethesda, Maryland, USA
| | - Ivana Darden
- Office of the Clinical Director, NHLBI, Bethesda, Maryland, USA
| | | | - Colin O Wu
- Office of Biostatistics Research, NHLBI, Bethesda, Maryland, USA
| | - Janis L Abkowitz
- Division of Hematology, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Cynthia E Dunbar
- Translational Stem Cell Biology Branch, NHLBI, Bethesda, Maryland, USA
| | - David J Young
- Translational Stem Cell Biology Branch, NHLBI, Bethesda, Maryland, USA
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2
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Serio B, Giudice V, Selleri C. All Roads Lead to Interferon-γ: From Known to Untraveled Pathways in Acquired Aplastic Anemia. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:2170. [PMID: 38138273 PMCID: PMC10744863 DOI: 10.3390/medicina59122170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/08/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023]
Abstract
Bone marrow failure (BMF) syndromes are a heterogeneous group of benign hematological conditions with common clinical features including reduced bone marrow cellularity and peripheral blood cytopenias. Acquired aplastic anemia (AA) is caused by T helper(Th)1-mediated immune responses and cytotoxic CD8+ T cell-mediated autologous immune attacks against hematopoietic stem and progenitor cells (HSPCs). Interferon-γ (IFNγ), tumor necrosis factor-α, and Fas-ligand are historically linked to AA pathogenesis because they drive Th1 and cytotoxic T cell-mediated responses and can directly induce HSPC apoptosis and differentiation block. The use of omics technologies has amplified the amount of data at the single-cell level, and knowledge on AA, and new scenarios, have been opened on "old" point of view. In this review, we summarize the current state-of-art of the pathogenic role of IFNγ in AA from initial findings to novel evidence, such as the involvement of the HIF-1α pathway, and how this knowledge can be translated in clinical practice.
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Affiliation(s)
- Bianca Serio
- Department of Medicine, Surgery, and Dentistry “Scuola Medica Salernitana”, University of Salerno, 84081 Baronissi, Italy; (B.S.); (C.S.)
| | - Valentina Giudice
- Department of Medicine, Surgery, and Dentistry “Scuola Medica Salernitana”, University of Salerno, 84081 Baronissi, Italy; (B.S.); (C.S.)
- Hematology and Transplant Center, University Hospital “San Giovanni di Dio e Ruggi d’Aragona”, 84131 Salerno, Italy
| | - Carmine Selleri
- Department of Medicine, Surgery, and Dentistry “Scuola Medica Salernitana”, University of Salerno, 84081 Baronissi, Italy; (B.S.); (C.S.)
- Hematology and Transplant Center, University Hospital “San Giovanni di Dio e Ruggi d’Aragona”, 84131 Salerno, Italy
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3
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Pan P, Chen C, Hong J, Gu Y. Autoimmune pathogenesis, immunosuppressive therapy and pharmacological mechanism in aplastic anemia. Int Immunopharmacol 2023; 117:110036. [PMID: 36940553 DOI: 10.1016/j.intimp.2023.110036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/26/2023] [Accepted: 03/10/2023] [Indexed: 03/23/2023]
Abstract
Acquired aplastic anemia (AA) is an autoimmune disease of bone marrow failure mediated by abnormally activated T cells, manifested by severe depletion of hematopoietic stem and progenitor cells (HSPCs) and peripheral blood cells. Due to the limitation of donors for hematopoietic stem cell transplantation, immunosuppressive therapy (IST) is currently an effective first-line treatment. However, a significant proportion of AA patients remain ineligible for IST, relapse, and develop other hematologic malignancies, such as acute myeloid leukemia after IST. Therefore, it is important to elucidate the pathogenic mechanisms of AA and to identify treatable molecular targets, which is an attractive way to improve these outcomes. In this review, we summarize the immune-related pathogenesis of AA, pharmacological targets, and clinical effects of the current mainstream immunosuppressive agents. It provides new insight into the combination of immunosuppressive drugs with multiple targets, as well as the discovery of new druggable targets based on current intervention pathways.
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Affiliation(s)
- Pengpeng Pan
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Institute of Clinical Pharmacology, Anhui Medical University, Hefei 230032, PR China
| | - Congcong Chen
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Institute of Clinical Pharmacology, Anhui Medical University, Hefei 230032, PR China
| | - Jian Hong
- Department of Hematology, The First Affiliated Hospital of Anhui Medical University, Hefei 230032, PR China
| | - Yue Gu
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Institute of Clinical Pharmacology, Anhui Medical University, Hefei 230032, PR China.
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4
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Young DJ, Fan X, Groarke EM, Patel B, Desmond R, Winkler T, Larochelle A, Calvo KR, Young NS, Dunbar CE. Long-term eltrombopag for bone marrow failure depletes iron. Am J Hematol 2022; 97:791-801. [PMID: 35312200 DOI: 10.1002/ajh.26543] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 11/09/2022]
Abstract
Eltrombopag (EPAG) has been approved for the treatment of aplastic anemia and for immune thrombocytopenia, and a subset of patients require long-term therapy. Due to polyvalent cation chelation, prolonged therapy leads to previously underappreciated iron depletion. We conducted a retrospective review of patients treated at the NIH for aplastic anemia, myelodysplastic syndrome, and unilineage cytopenias, comparing those treated with EPAG to a historical cohort treated with immunosuppression without EPAG. We examined iron parameters, duration of therapy, response assessment, relapse rates, and common demographic parameters. We included 521 subjects treated with (n = 315) or without EPAG (n = 206) across 11 studies with multiyear follow-up (3.6 vs. 8.5 years, respectively). Duration of EPAG exposure correlated with ferritin reduction (p = 4 × 10-14 ) regardless of response, maximum dose, or degree of initial iron overload. Clearance followed first-order kinetics with faster clearance (half-life 15.3 months) compared with historical responders (47.5 months, p = 8 × 10-10 ). Risk of iron depletion was dependent upon baseline ferritin and duration of therapy. Baseline ferritin did not correlate with response of marrow failure to EPAG or to relapse risk, and timing of iron clearance did not correlate with disease response. In conclusion, EPAG efficiently chelates total body iron comparable to clinically available chelators. Prolonged use can deplete iron and ultimately lead to iron-deficiency anemia mimicking relapse, responsive to iron supplementation.
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Affiliation(s)
- David J. Young
- Translational Stem Cell Biology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
| | - Xing Fan
- Translational Stem Cell Biology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
| | - Emma M. Groarke
- Hematology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
| | - Bhavisha Patel
- Hematology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
| | - Ronan Desmond
- Hematology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
- Department of Haematology (Laboratory) Tallaght University Hospital Dublin Ireland
| | - Thomas Winkler
- Translational Stem Cell Biology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
| | - Andre Larochelle
- Cellular and Molecular Therapeutics Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
| | - Katherine R. Calvo
- Department of Laboratory Medicine Clinical Center, NIH Bethesda Maryland USA
| | - Neal S. Young
- Hematology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
| | - Cynthia E. Dunbar
- Translational Stem Cell Biology Branch National Heart, Lung, and Blood Institute, NIH Bethesda Maryland USA
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5
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Tarantini F, Cumbo C, Anelli L, Zagaria A, Conserva MR, Redavid I, Specchia G, Musto P, Albano F. Exploring the Potential of Eltrombopag: Room for More? Front Pharmacol 2022; 13:906036. [PMID: 35677428 PMCID: PMC9168361 DOI: 10.3389/fphar.2022.906036] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 05/06/2022] [Indexed: 11/26/2022] Open
Abstract
Since its introduction in clinical practice, eltrombopag (ELT) has demonstrated efficacy in heterogeneous clinical contexts, encompassing both benign and malignant diseases, thus leading researchers to make a more in-depth study of its mechanism of action. As a result, a growing body of evidence demonstrates that ELT displays many effects ranging from native thrombopoietin agonism to immunomodulation, anti-inflammatory, and metabolic properties. These features collectively explain ELT effectiveness in a broad spectrum of indications; moreover, they suggest that ELT could be effective in different, challenging clinical scenarios. We reviewed the extended ELT mechanism of action in various diseases, with the aim of further exploring its full potential and hypothesize new, fascinating indications.
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Affiliation(s)
- Francesco Tarantini
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
| | - Cosimo Cumbo
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
| | - Luisa Anelli
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
| | - Antonella Zagaria
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
| | - Maria Rosa Conserva
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
| | - Immacolata Redavid
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
| | | | - Pellegrino Musto
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
| | - Francesco Albano
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari “Aldo Moro”, Bari, Italy
- *Correspondence: Francesco Albano,
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6
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Ding S, Fu R. New Trends of Nontransplant therapy for Acquired Aplastic Anemia. Curr Pharm Des 2022; 28:1730-1737. [PMID: 35440301 DOI: 10.2174/1381612828666220418132432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 03/03/2022] [Indexed: 11/22/2022]
Abstract
Aplastic anemia (AA) is a hematological disease that is characterized by pancytopenia and hypofunctional bone marrow hematopoiesis. Patients with AA are treated with either immunosuppressive therapy (IST) using anti-thymocyte globulin (ATG) and Cyclosporine (CsA) or hematopoietic stem cell transplantation (HSCT), if a matched donor is available. The standard IST regimen for AA patients which results in response rates up to 70%, and even higher overall survival. However, primary and secondary failures after IST remain frequent, and to date all attempts aiming to overcome this problem have been unfruitful. The nontransplant therapeutic options for AA have significantly expanded during the last few years. Here, we review the new trends of nontransplant therapy for AA and summarize the current therapeutic effect of AA.
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Affiliation(s)
- Shaoxue Ding
- Department of Hematology, Tianjin Medical University General Hospital, No. 154, Anshan Road, Heping District, Tianjin, 300052, China
| | - Rong Fu
- Department of Hematology, Tianjin Medical University General Hospital, No. 154, Anshan Road, Heping District, Tianjin, 300052, China
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7
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Studies in a mosaic DBA patient and chimeric mice reveal erythroid cell-extrinsic contributions to erythropoiesis. Blood 2022; 139:3439-3449. [PMID: 35349664 DOI: 10.1182/blood.2021013507] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 03/15/2022] [Indexed: 11/20/2022] Open
Abstract
We follow a Diamond Blackfan anemia (DBA) patient mosaic for a pathogenic RPS19 haploinsufficiency mutation with persistent transfusion-dependent anemia. Her anemia remitted on eltrombopag (EPAG), but surprisingly mosaicism was unchanged, suggesting both mutant and normal cells responded. When EPAG was held, her anemia returned. In addition to expanding hematopoietic stem/progenitor cells, EPAG aggressively chelates iron. Since DBA anemia, at least in part, results from excessive intracellular heme leading to ferroptotic cell death, we hypothesized that the excess heme accumulating in ribosomal protein-deficient erythroid precursors inhibited the growth of adjacent genetically-normal precursors, and that the efficacy of EPAG reflected its ability to chelate iron, limit heme synthesis, and thus limit toxicity in both mutant and normal cells. To test this, we studied Rpl11 haploinsufficient (DBA) mice and mice chimeric for the cytoplasmic heme export protein, FLVCR. Flvcr1-deleted mice have severe anemia, resembling DBA. Mice transplanted with ratios of DBA to wildtype marrow cells of 50:50 are anemic, like our DBA patient. In contrast, mice transplanted with Flvcr1-deleted (unable to export heme) and wildtype marrow cells at ratios of 50:50 or 80:20 have normal numbers of red cells. Additional studies suggest that heme exported from DBA erythroid cells might impede the nurse cell function of central macrophages of erythroblastic islands to impair the maturation of genetically-normal co-adherent erythroid cells. These findings have implications for the gene therapy of DBA and may provide insights into why del(5q) myelodysplastic syndrome patients are anemic despite being mosaic for chromosome 5q deletion and loss of RPS14.
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8
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Guan Y, Hasipek M, Jiang D, Tiwari AD, Grabowski DR, Pagliuca S, Kongkiatkamon S, Patel B, Singh S, Parker Y, LaFramboise T, Lindner D, Sekeres MA, Mian OY, Saunthararajah Y, Maciejewski JP, Jha BK. Eltrombopag inhibits TET dioxygenase to contribute to hematopoietic stem cell expansion in aplastic anemia. J Clin Invest 2022; 132:e149856. [PMID: 35085104 PMCID: PMC8843742 DOI: 10.1172/jci149856] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 01/04/2022] [Indexed: 11/18/2022] Open
Abstract
Eltrombopag, an FDA-approved non-peptidyl thrombopoietin receptor agonist, is clinically used for the treatment of aplastic anemia, a disease characterized by hematopoietic stem cell failure and pancytopenia, to improve platelet counts and stem cell function. Eltrombopag treatment results in a durable trilineage hematopoietic expansion in patients. Some of the eltrombopag hematopoietic activity has been attributed to its off-target effects, including iron chelation properties. However, the mechanism of action for its full spectrum of clinical effects is still poorly understood. Here, we report that eltrombopag bound to the TET2 catalytic domain and inhibited its dioxygenase activity, which was independent of its role as an iron chelator. The DNA demethylating enzyme TET2, essential for hematopoietic stem cell differentiation and lineage commitment, is frequently mutated in myeloid malignancies. Eltrombopag treatment expanded TET2-proficient normal hematopoietic stem and progenitor cells, in part because of its ability to mimic loss of TET2 with simultaneous thrombopoietin receptor activation. On the contrary, TET inhibition in TET2 mutant malignant myeloid cells prevented neoplastic clonal evolution in vitro and in vivo. This mechanism of action may offer a restorative therapeutic index and provide a scientific rationale to treat selected patients with TET2 mutant-associated or TET deficiency-associated myeloid malignancies.
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Affiliation(s)
- Yihong Guan
- Department of Translational Hematology and Oncology Research and
| | - Metis Hasipek
- Department of Translational Hematology and Oncology Research and
| | - Dongxu Jiang
- Department of Translational Hematology and Oncology Research and
| | - Anand D. Tiwari
- Department of Translational Hematology and Oncology Research and
| | | | - Simona Pagliuca
- Department of Translational Hematology and Oncology Research and
| | | | - Bhumika Patel
- Leukemia Program, Department of Hematologic Oncology and Blood Disorders, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Salendra Singh
- Department of Genetics and Genome Sciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Yvonne Parker
- Department of Translational Hematology and Oncology Research and
| | - Thomas LaFramboise
- Department of Genetics and Genome Sciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Daniel Lindner
- Department of Translational Hematology and Oncology Research and
- Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio, USA
- Developmental Therapeutics, Case Comprehensive Cancer Center, Cleveland, Ohio, USA
| | - Mikkael A. Sekeres
- Leukemia Program, Department of Hematologic Oncology and Blood Disorders, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Omar Y. Mian
- Department of Translational Hematology and Oncology Research and
- Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio, USA
- Developmental Therapeutics, Case Comprehensive Cancer Center, Cleveland, Ohio, USA
| | - Yogen Saunthararajah
- Department of Translational Hematology and Oncology Research and
- Leukemia Program, Department of Hematologic Oncology and Blood Disorders, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio, USA
- Developmental Therapeutics, Case Comprehensive Cancer Center, Cleveland, Ohio, USA
| | - Jaroslaw P. Maciejewski
- Department of Translational Hematology and Oncology Research and
- Leukemia Program, Department of Hematologic Oncology and Blood Disorders, Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio, USA
- Developmental Therapeutics, Case Comprehensive Cancer Center, Cleveland, Ohio, USA
| | - Babal K. Jha
- Department of Translational Hematology and Oncology Research and
- Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, Ohio, USA
- Developmental Therapeutics, Case Comprehensive Cancer Center, Cleveland, Ohio, USA
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9
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Liu ZJ, Deschmann E, Ramsey HE, Feldman HA, Psaila B, Cooper N, Vlachodimitropoulou E, Porter J, Bussel J, Georgieff M, Sola-Visner M. Iron status influences the response of cord blood megakaryocyte progenitors to eltrombopag in vitro. Blood Adv 2022; 6:13-27. [PMID: 34654056 PMCID: PMC8753208 DOI: 10.1182/bloodadvances.2021004207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 09/17/2021] [Indexed: 11/20/2022] Open
Abstract
Eltrombopag (ELT) is a thrombopoietic agent approved for immune thrombocytopenia and also a potent iron chelator. Here we found that ELT exhibited dose-dependent opposing effects on in vitro megakaryopoiesis: low concentrations (≤6 µM, ELT6) stimulated megakaryopoiesis, but high concentrations (30 µM, ELT30) suppressed megakaryocyte (MK) differentiation and proliferation. The suppressive effects of ELT30 were reproduced by other iron chelators, supporting iron chelation as a likely mechanism. During MK differentiation, committed MK progenitors (CD34+/CD41+ and CD34-/CD41+ cells) were significantly more sensitive than undifferentiated progenitors (CD34+/CD41- cells) to the suppressive effects of ELT30, which resulted from both decreased proliferation and increased apoptosis. The antiproliferative effects of ELT30 were reversed by increased iron in the culture, as were the proapoptotic effects when exposure to ELT30 was short. Because committed MK progenitors exhibited the highest proliferative rate and the highest sensitivity to iron chelation, we tested whether their iron status influenced their response to ELT during rapid cell expansion. In these studies, iron deficiency reduced the proliferation of CD41+ cells in response to all ELT concentrations. Severe iron deficiency also reduced the number of MKs generated in response to high thrombopoietin concentrations by ∼50%, compared with iron-replete cultures. Our findings support the hypothesis that although iron deficiency can stimulate certain cells and steps in megakaryopoiesis, it can also limit the proliferation of committed MK progenitors, with severity of iron deficiency and degree of thrombopoietic stimulation influencing the ultimate output. Further studies are needed to clarify how megakaryopoiesis, iron deficiency, and ELT stimulation are clinically interrelated.
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Affiliation(s)
- Zhi-Jian Liu
- Department of Pediatrics, Harvard Medical School, Boston, MA
- Division of Newborn Medicine, Boston Children’s Hospital, Boston, MA
| | - Emoke Deschmann
- Division of Neonatology, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Haley E. Ramsey
- Department of Medicine, Vanderbilt University, Nashville, TN
| | - Henry A. Feldman
- Department of Pediatrics, Harvard Medical School, Boston, MA
- Division of Newborn Medicine, Boston Children’s Hospital, Boston, MA
| | - Bethan Psaila
- Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Nichola Cooper
- Department of Immunology and Inflammation, Imperial College London, London, United Kingdom
| | | | - John Porter
- Department of Hematology, University College London, London, United Kingdom
| | - James Bussel
- Division of Hematology, Department of Pediatrics, Weill Cornell Medicine, New York, NY; and
| | - Michael Georgieff
- Department of Pediatrics, Center for Neurobehavioral Development, University of Minnesota, Minneapolis, MN
| | - Martha Sola-Visner
- Department of Pediatrics, Harvard Medical School, Boston, MA
- Division of Newborn Medicine, Boston Children’s Hospital, Boston, MA
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10
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Huang L, Tian M, Liu Z, Liu C, Fu R. Deferasirox combination with eltrombopag shows anti-myelodysplastic syndrome effects by enhancing iron deprivation-related apoptosis. J Investig Med 2021; 70:953-962. [PMID: 34921125 DOI: 10.1136/jim-2021-002147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2021] [Indexed: 11/04/2022]
Abstract
Iron overload (IO) affected the survival of patients with myelodysplastic syndrome (MDS). Deferasirox (DFX) is widely used in patients with MDS for iron chelation therapy, but is not suitable for MDS patients with severe thrombocytopenia. Eltrombopag (ELT) is a type of thrombopoietin receptor (TPOR) analog used in the treatment of thrombocytopenia. Therefore, we sought to explore the synergistic effects and possible mechanisms of DFX combination with ELT in MDS cells. In our study, the combination of DFX with ELT synergistically inhibited proliferation, induced apoptosis and arrested cell cycle of MDS cells. Through the RNA-sequence and gene set enrichment analysis (GSEA), iron metabolism-related pathway played important roles in apoptosis of SKM-1 cells treated with DFX plus ELT. Transferrin receptor (TFRC) was significantly highly expressed in combination group than that in single agent groups, without affecting TPOR. Furthermore, the apoptosis of the combination group MDS cells could be partially reversed by ferric ammonium citrate (FAC), accompanied with decreased expression of TFRC. These results suggested that the combination of DFX and ELT synergistically induced apoptosis of MDS cells by enhancing iron deprivation-related pathway.
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Affiliation(s)
- Lei Huang
- Hematology, Tianjin Medical University General Hospital, Tianjin, China
| | - Mengyue Tian
- Hematology, Tianjin Medical University General Hospital, Tianjin, China
| | - Zhaoyun Liu
- Hematology, Tianjin Medical University General Hospital, Tianjin, China
| | - Chunyan Liu
- Hematology, Tianjin Medical University General Hospital, Tianjin, China
| | - Rong Fu
- Hematology, Tianjin Medical University General Hospital, Tianjin, China
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11
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Gao Y, Gao F, Shi J, Fu H, Huang H, Zhao Y. Successful treatment of refractory pure red cell aplasia with eltrombopag after ABO-incompatible allogeneic hematopoietic stem cell transplantation. J Zhejiang Univ Sci B 2021; 22:695-700. [PMID: 34414703 DOI: 10.1631/jzus.b2000532] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Pure red cell aplasia (PRCA) is a well-recognized complication of ABO major mismatched allogeneic hematopoietic stem cell transplantation (allo-HSCT), with a reported incidence of 10%-20% (Zhidong et al., 2012; Busca et al., 2018). It is clinically characterized by anemia, reticulocytopenia, and the absence of erythroblasts in a normal-appearing bone marrow biopsy (Shahan and Hildebrandt, 2015). The mechanism for PRCA has been presumed to be persistence of recipient isoagglutinins, produced by residual host B lymphocytes or plasma cells, which can interfere with the engraftment of donor erythroid cells (Zhidong et al., 2012). Several risk factors of PRCA at presentation are known, such as presence of anti-A isoagglutinins before transplantation, reduced intensity conditioning, absence of acute graft-versus-host disease (GVHD), sibling donors, and cyclosporin A (CsA) as GVHD prophylaxis (Hirokawa et al., 2013). PRCA is not considered to be a barrier to HSCT, as some patients can recover spontaneously or benefit from various approaches including high-dose steroids, erythropoietin (EPO), plasma exchange, immunoadsorption, donor lymphocyte infusion (DLI), treatment with rituximab, bortezomib, or daratumumab, and tapering or discontinuation of immunosuppression (Hirokawa et al., 2013; Bathini et al., 2019). However, there are still some patients who fail to respond even to aggressive treatment; they become red cell transfusion-dependent and iron-overloaded, and their life quality is impaired.
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Affiliation(s)
- Yang Gao
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.,Institute of Hematology, Zhejiang University, Hangzhou 310058, China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou 310058, China
| | - Fei Gao
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.,Institute of Hematology, Zhejiang University, Hangzhou 310058, China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou 310058, China
| | - Jimin Shi
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.,Institute of Hematology, Zhejiang University, Hangzhou 310058, China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou 310058, China
| | - Huarui Fu
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.,Institute of Hematology, Zhejiang University, Hangzhou 310058, China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou 310058, China
| | - He Huang
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China. .,Institute of Hematology, Zhejiang University, Hangzhou 310058, China. .,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou 310058, China.
| | - Yanmin Zhao
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China. .,Institute of Hematology, Zhejiang University, Hangzhou 310058, China. .,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou 310058, China.
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12
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Eltrombopag for patients with moderate aplastic anemia or uni-lineage cytopenias. Blood Adv 2021; 4:1700-1710. [PMID: 32330244 DOI: 10.1182/bloodadvances.2020001657] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 03/19/2020] [Indexed: 12/26/2022] Open
Abstract
There is no standard or widely effective treatment of patients with moderate aplastic anemia (MAA) or hypo-productive uni-lineage cytopenias (UC). Eltrombopag (EPAG), a small molecule thrombopoietin mimetic, has previously been shown to result in durable multi-lineage hematologic responses with low toxicity in patients with refractory severe aplastic anemia (SAA). Its safety and efficacy in MAA are unknown. This prospective phase 2 study enrolled previously untreated and treated MAA and UC patients with clinically relevant cytopenias. EPAG was administered at doses escalating from 50 to 300 mg/d. Hematologic responses were assessed at 16 to 20 weeks. Responding patients were continued on EPAG until reaching defined robust or stable blood counts. EPAG was reinstituted for relapse. Thirty-four patients were enrolled between 2012 and 2017, including 31 with MAA and 3 with UC. Seventeen patients responded in at least 1 eligible lineage by the primary end point. A striking improvement in anemia was observed in a patient with Diamond-Blackfan anemia. EPAG was well tolerated, and it was discontinued for robust or stable blood counts in 12 of 17 patients after a median of 8 months. A majority required re-initiation of EPAG for declining counts, and all regained response. Two of 34 patients developed non-chromosome 7 bone marrow cytogenetic abnormalities while taking EPAG, without dysplasia or increased blasts. Somatic mutation allele frequencies in cancer genes did not increase overall on EPAG. EPAG is a well-tolerated oral treatment of cytopenias in patients with MAA/UC. This trial was registered at www.clinicaltrials.gov as #NCT01328587.
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13
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Scheinberg P. Acquired severe aplastic anaemia: how medical therapy evolved in the 20th and 21st centuries. Br J Haematol 2021; 194:954-969. [PMID: 33855695 DOI: 10.1111/bjh.17403] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 02/16/2021] [Indexed: 11/28/2022]
Abstract
The progress in aplastic anaemia (AA) management is one of success. Once an obscure entity resulting in death in most affected can now be successfully treated with either haematopoietic stem cell transplantation (HSCT) or immunosuppressive therapy (IST). The mechanisms that underly the diminution of haematopoietic stem cells (HSCs) are now better elucidated, and include genetics and immunological alterations. Advances in supportive care with better antimicrobials, safer blood products and iron chelation have greatly impacted AA outcomes. Working somewhat 'mysteriously', anti-thymocyte globulin (ATG) forms the base for both HSCT and IST protocols. Efforts to augment immunosuppression potency have not, unfortunately, led to better outcomes. Stimulating HSCs, an often-sought approach, has not been effective historically. The thrombopoietin receptor agonists (Tpo-RA) have been effective in stimulating early HSCs in AA despite the high endogenous Tpo levels. Dosing, timing and best combinations with Tpo-RAs are being defined to improve HSCs expansion in AA with minimal added toxicity. The more comprehensive access and advances in HSCT and IST protocols are likely to benefit AA patients worldwide. The focus of this review will be on the medical treatment advances in AA.
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Affiliation(s)
- Phillip Scheinberg
- Division of Haematology, Hospital A Beneficência Portuguesa, São Paulo, Brazil
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14
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Qanash H, Li Y, Smith RH, Linask K, Young-Baird S, Hakami W, Keyvanfar K, Choy JS, Zou J, Larochelle A. Eltrombopag Improves Erythroid Differentiation in a Human Induced Pluripotent Stem Cell Model of Diamond Blackfan Anemia. Cells 2021; 10:734. [PMID: 33810313 PMCID: PMC8065708 DOI: 10.3390/cells10040734] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/17/2021] [Accepted: 03/22/2021] [Indexed: 12/15/2022] Open
Abstract
Diamond Blackfan Anemia (DBA) is a congenital macrocytic anemia associated with ribosomal protein haploinsufficiency. Ribosomal dysfunction delays globin synthesis, resulting in excess toxic free heme in erythroid progenitors, early differentiation arrest, and pure red cell aplasia. In this study, DBA induced pluripotent stem cell (iPSC) lines were generated from blood mononuclear cells of DBA patients with inactivating mutations in RPS19 and subjected to hematopoietic differentiation to model disease phenotypes. In vitro differentiated hematopoietic cells were used to investigate whether eltrombopag, an FDA-approved mimetic of thrombopoietin with robust intracellular iron chelating properties, could rescue erythropoiesis in DBA by restricting the labile iron pool (LIP) derived from excessive free heme. DBA iPSCs exhibited RPS19 haploinsufficiency, reduction in the 40S/60S ribosomal subunit ratio and early erythroid differentiation arrest in the absence of eltrombopag, compared to control isogenic iPSCs established by CRISPR/Cas9-mediated correction of the RPS19 point mutation. Notably, differentiation of DBA iPSCs in the presence of eltrombopag markedly improved erythroid maturation. Consistent with a molecular mechanism based on intracellular iron chelation, we observed that deferasirox, a clinically licensed iron chelator able to permeate into cells, also enhanced erythropoiesis in our DBA iPSC model. In contrast, erythroid maturation did not improve substantially in DBA iPSC differentiation cultures supplemented with deferoxamine, a clinically available iron chelator that poorly accesses LIP within cellular compartments. These findings identify eltrombopag as a promising new therapeutic to improve anemia in DBA.
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Affiliation(s)
- Husam Qanash
- Cellular and Molecular Therapeutics Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA; (H.Q.); (Y.L.); (R.H.S.); (W.H.)
- Department of Biology, Catholic University of America, Washington, DC 20064, USA;
- Department of Medical Laboratory Science, College of Applied Medical Sciences, The University of Hail, Hail 55476, Saudi Arabia
| | - Yongqin Li
- Cellular and Molecular Therapeutics Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA; (H.Q.); (Y.L.); (R.H.S.); (W.H.)
| | - Richard H. Smith
- Cellular and Molecular Therapeutics Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA; (H.Q.); (Y.L.); (R.H.S.); (W.H.)
| | - Kaari Linask
- iPSC Core Facility, NHLBI, NIH, Bethesda, MD 20892, USA; (K.L.); (J.Z.)
| | - Sara Young-Baird
- Eunice Kennedy Shriver, National Institute of Child Health and Human Development, NIH, Bethesda, MD 20892, USA;
- National Institute of General Medical Sciences (NIGMS), NIH, Bethesda, MD 20892, USA
| | - Waleed Hakami
- Cellular and Molecular Therapeutics Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA; (H.Q.); (Y.L.); (R.H.S.); (W.H.)
- Department of Biology, Catholic University of America, Washington, DC 20064, USA;
- Department of Medical Laboratories Technology, College of Applied Medical Sciences, Jazan University, Jazan 45142, Saudi Arabia
| | - Keyvan Keyvanfar
- Clinical Flow Core Facility, NHLBI, NIH, Bethesda, MD 20892, USA;
| | - John S. Choy
- Department of Biology, Catholic University of America, Washington, DC 20064, USA;
| | - Jizhong Zou
- iPSC Core Facility, NHLBI, NIH, Bethesda, MD 20892, USA; (K.L.); (J.Z.)
| | - Andre Larochelle
- Cellular and Molecular Therapeutics Branch, National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20892, USA; (H.Q.); (Y.L.); (R.H.S.); (W.H.)
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15
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Drexler B, Passweg J. Current evidence and the emerging role of eltrombopag in severe aplastic anemia. Ther Adv Hematol 2021; 12:2040620721998126. [PMID: 33747425 PMCID: PMC7940771 DOI: 10.1177/2040620721998126] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 02/02/2021] [Indexed: 12/12/2022] Open
Abstract
Acquired aplastic anemia (AA) is characterized by a reduced stem cell reserve. Several preclinical studies have confirmed the beneficial effect of thrombopoietin (TPO) on the expansion and maintenance of hematopoietic stem cells (HSCs). Thus, TPO receptor agonists seem to be an ideal therapeutic agent for AA to augment marrow function. First studies with eltrombopag as a single agent at 150 mg/day showed an overall response rate of 40–50% in patients with refractory severe AA (rSAA). Subsequent studies examined the first-line use of eltrombopag together with horse antithymocyte globulin and cyclosporine, reaching response rates up to 94%. Although used at high doses, known adverse events in the form of skin, gastrointestinal, or hepatic impairment are feasible in AA, however first data show a relatively high rate of clonal evolution in the form of karyotypic aberrations in patients with rAA. Nonetheless, there is a strong rationale that eltrombopag can contribute to restoring hematopoiesis in SAA by stimulating HSCs. Further studies are needed to decide if eltrombopag is clearly superior to current established treatments and to determine optimal treatment duration, dosage, and long-term effects.
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Affiliation(s)
- Beatrice Drexler
- Division of Hematology, University Hospital Basel, Petersgraben 4, Basel, 4031, Switzerland
| | - Jakob Passweg
- Division of Hematology, University Hospital Basel, Basel, Switzerland
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16
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Argenziano M, Di Paola A, Tortora C, Di Pinto D, Pota E, Di Martino M, Perrotta S, Rossi F, Punzo F. Effects of Iron Chelation in Osteosarcoma. Curr Cancer Drug Targets 2020; 21:443-455. [PMID: 33380300 DOI: 10.2174/1568009620666201230090531] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 10/19/2020] [Accepted: 10/25/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Osteosarcoma is an aggressive bone tumor. It represents the principal cause of cancer-associated death in children. Considering the recent findings on the role of iron in cancer, iron chelation has been investigated for its antineoplastic properties in many tumors. Deferasirox is the most used iron chelator compound and in previous studies showed an anticancer effect in hematologic and solid malignancies. Eltrombopag is a Thrombopoietin receptor used in thrombocytopenia that also binds and mobilize iron. It demonstrated an effect on iron overload conditions and also in contrasting cancer cell proliferation. OBJECTIVE We analyzed the effects of deferasirox and eltrombopag in human osteosarcoma cells in an attempt to identify other therapeutic approaches for this tumor. METHODS We cultured and treated with deferasirox and Eltrombopag, alone and in combination, two human osteosarcoma cell lines, MG63 and 143B. After 72h exposure, we performed RTqPCR, Western Blotting, Iron Assay and cytofluorimetric assays to evaluate the effect on viability, apoptosis, cell cycle progression and ROS production. RESULTS The iron-chelating properties of the two compounds are also confirmed in osteosarcoma, but we did not observe any direct effect on tumor progression. DISCUSSION We tested deferasirox and eltrombopag, alone and in combination, in human osteosarcoma cells for the first time and demonstrated that their iron-chelating activity does not influence biochemical pathways related to cancer progression and maintenance. CONCLUSION Although further investigations on possible effects mediated by cells of the tumor microenvironment could be of great interest, in vitro iron chelation in osteosarcoma does not impair tumor progression.
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Affiliation(s)
- Maura Argenziano
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Alessandra Di Paola
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Chiara Tortora
- Department of Woman, Child and General and Specialist Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Daniela Di Pinto
- Department of Woman, Child and General and Specialist Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Elvira Pota
- Department of Woman, Child and General and Specialist Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Martina Di Martino
- Department of Woman, Child and General and Specialist Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Silverio Perrotta
- Department of Woman, Child and General and Specialist Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Francesca Rossi
- Department of Woman, Child and General and Specialist Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Francesca Punzo
- Department of Woman, Child and General and Specialist Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
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17
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Abstract
Aplastic anemia (AA) in its severe form has historically been associated with high mortality. With limited supportive care and no effective strategy to reverse marrow failure, most patients diagnosed with severe AA (SAA) died of pancytopenia complications. Since the 1970s, hematopoietic stem cell transplantation (HSCT) and immunosuppressive therapy (IST) have changed SAA's natural history by improving marrow function and pancytopenia. Standard IST with horse anti-thymocyte globulin plus cyclosporine produces a hematologic response rate of 60 to 70%. In the long term, about one-third of patients relapse, and 10 to 15% can develop cytogenetic abnormalities. Outcomes with either HSCT or IST are similar, and choosing between these modalities relies on age, availability of a histocompatible donor, comorbidities, and patient preference. The introduction of eltrombopag, a thrombopoietin receptor agonist, improved SAA outcomes as both salvage (second-line) and upfront therapy combined with IST. As a single agent, eltrombopag in doses up to 150 mg daily improved cytopenias in 40 to 50% in those who failed initial IST, which associated with higher marrow cellularity, suggesting a pan-stimulatory marrow effect. When eltrombopag was combined with IST as upfront therapy, overall (about 90%) and complete responses (about 50%) were higher than observed extensively with IST alone of 65% and 10%, respectively. Not surprisingly, given the strong correlation between hematologic response rates and survival in SAA, most (>90%) were alive after a median follow-up of 18 months. Longer follow-up and real-word data continue to confirm the activity of this agent in AA. The use of eltrombopag in different combinations and doses are currently being explored. The activity of another thrombopoietin receptor agonist in AA, romiplostim, suggests a class effect. In the coming years, the mechanisms of their activity and the most optimal regimen are likely to be elucidated.
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Affiliation(s)
- Phillip Scheinberg
- Division of Hematology, Hospital A Beneficência Portuguesa, São Paulo, Brazil
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18
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Eltrombopag is effective in patients with relapse/refractory aplastic anemia—report from a single center in China. Ann Hematol 2020; 99:2755-2761. [DOI: 10.1007/s00277-020-04266-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 09/07/2020] [Indexed: 02/07/2023]
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19
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Koca Yozgat A, Leblebisatan G, Akbayram S, Çınar Özel S, Karakaş Z, Erduran E, Yılmaz Ş, Koçak Ü, Ünal Ş, Özdemir GN, Albayrak M, Zengin E, Oymak Y, Bör Ö, Çakmaklı HF, Söker M, Gürlek Gökçebay D, Tokgöz H, Malbora B, Karaman S, Celkan T, Şaşmaz İ, Yaralı N, Ören H, Ünüvar A, Özbek NY. Outcomes of Eltrombopag Treatment and Development of Iron Deficiency in Children with Immune Thrombocytopenia in Turkey. Turk J Haematol 2020; 37:139-144. [PMID: 32181630 PMCID: PMC7463208 DOI: 10.4274/tjh.galenos.2020.2019.0380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Objective Immune thrombocytopenia (ITP) is a rare autoimmune disease and hematologic disorder characterized by reduced platelet counts that can result in significant symptoms, such as bleeding, bruising, epistaxis, or petechiae. The thrombopoietin receptor agonist eltrombopag (EPAG) is a second-line agent used to treat chronic ITP purpura in adults and children. Materials and Methods The present retrospective study evaluated the efficacy, safety, and side effects of EPAG treatment in pediatric patients with acute refractory and chronic immune thrombocytopenia, particularly focusing on iron-deficiency anemia. Results The diagnosis was chronic ITP in 89 patients and acute refractory ITP in 16 patients. The mean age of patients was 9.5±4.5 years (minimum-maximum: 1.2-18 years) at the beginning of EPAG treatment. The overall response rate was 74.3% (n=78). The mean time for platelet count of ≥50x109/L was 11.6±8 weeks (range: 1-34 weeks). The treatment was stopped for 27 patients (25.7%) at an average of 6.8±9 months (range: 1-38 months). The reason for discontinuation was lack of response in 18 patients, nonadherence in 4 patients, and hepatotoxicity in 2 patients. Response to treatment continued for an average of 4 months after cessation of EPAG in 3 patients. Conclusion Results of the current study imply that EPAG is an effective therapeutic option in pediatric patients with acute refractory and chronic ITP. However, patients must be closely monitored for response and side effects during treatment, and especially for iron deficiency.
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Affiliation(s)
- Ayça Koca Yozgat
- Ankara City Hospital, Clinic of Pediatric Hematology, Ankara, Turkey
| | - Göksel Leblebisatan
- Çukurova University Faculty of Medicine, Department of Pediatric Hematology, Adana, Turkey
| | - Sinan Akbayram
- Gaziantep University Faculty of Medicine, Department of Pediatric Hematology, Gaziantep, Turkey
| | - Simge Çınar Özel
- İstanbul University-Cerrahpaşa Cerrahpaşa Faculty of Medicine, Department of Pediatric Hematology, İstanbul, Turkey
| | - Zeynep Karakaş
- İstanbul University, İstanbul Faculty of Medicine, Department of Pediatric Hematology, İstanbul, Turkey
| | - Erol Erduran
- Karadeniz Technical University Faculty of Medicine, Department of Pediatric Hematology, Trabzon, Turkey
| | - Şebnem Yılmaz
- Dokuz Eylül University Faculty of Medicine, Department of Pediatric Hematology, İzmir, Turkey
| | - Ülker Koçak
- Gazi University Faculty of Medicine, Department of Pediatric Hematology, Ankara, Turkey
| | - Şule Ünal
- Hacettepe University Faculty of Medicine, Department of Pediatric Hematology, Ankara, Turkey
| | - Gül Nihal Özdemir
- Kanuni Sultan Süleyman Training and Research Hospital, Clinic of Pediatric Hematology, İstanbul, Turkey
| | - Meryem Albayrak
- Kırıkkale University Faculty of Medicine, Department of Pediatric Hematology, Kırıkkale, Turkey
| | - Emine Zengin
- Kocaeli University Faculty of Medicine, Department of Pediatric Hematology, Kocaeli, Turkey
| | - Yeşim Oymak
- Dr. Behçet Uz Children’s Training and Research Hospital, Clinic of Pediatric Hematology, İzmir, Turkey
| | - Özcan Bör
- Eskişehir University Faculty of Medicine, Department of Pediatric Hematology, Eskişehir, Turkey
| | - Hasan Fatih Çakmaklı
- Ankara University Faculty of Medicine, Department of Pediatric Hematology, Ankara, Turkey
| | - Murat Söker
- Dicle University Faculty of Medicine, Department of Pediatric Hematology, Diyarbakır, Turkey
| | - Dilek Gürlek Gökçebay
- Ankara Keçiören Training and Research Hospital, Clinic of Pediatric Hematology, Ankara, Turkey
| | - Hüseyin Tokgöz
- Necmettin Erbakan University Meram Faculty of Medicine, Department of Pediatric Hematology, Konya, Turkey
| | - Barış Malbora
- Yeni Yüzyıl University, Gaziosmanpaşa Hospital, Clinic of Pediatric Hematology, İstanbul, Turkey
| | - Serap Karaman
- İstanbul University, İstanbul Faculty of Medicine, Department of Pediatric Hematology, İstanbul, Turkey
| | - Tiraje Celkan
- İstanbul University-Cerrahpaşa Cerrahpaşa Faculty of Medicine, Department of Pediatric Hematology, İstanbul, Turkey
| | - İlgen Şaşmaz
- Çukurova University Faculty of Medicine, Department of Pediatric Hematology, Adana, Turkey
| | - Neşe Yaralı
- Ankara City Hospital, Clinic of Pediatric Hematology, Ankara, Turkey
| | - Hale Ören
- Dokuz Eylül University Faculty of Medicine, Department of Pediatric Hematology, İzmir, Turkey
| | - Ayşegül Ünüvar
- İstanbul University, İstanbul Faculty of Medicine, Department of Pediatric Hematology, İstanbul, Turkey
| | - Namık Yaşar Özbek
- Ankara City Hospital, Clinic of Pediatric Hematology, Ankara, Turkey
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20
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Hosokawa K, Yamazaki H, Tanabe M, Imi T, Sugimori N, Nakao S. High-dose romiplostim accelerates hematologic recovery in patients with aplastic anemia refractory to eltrombopag. Leukemia 2020; 35:906-909. [PMID: 32616921 DOI: 10.1038/s41375-020-0950-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 06/16/2020] [Accepted: 06/23/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Kohei Hosokawa
- Department of Hematology, Faculty of Medicine, Institute of Medical Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Hirohito Yamazaki
- Division of Transfusion Medicine, Kanazawa University Hospital, Kanazawa, Japan
| | - Mikoto Tanabe
- Department of Hematology, Faculty of Medicine, Institute of Medical Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Tatsuya Imi
- Department of Hematology, Faculty of Medicine, Institute of Medical Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Naomi Sugimori
- Department of Hematology, Faculty of Medicine, Institute of Medical Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Shinji Nakao
- Department of Hematology, Faculty of Medicine, Institute of Medical Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan.
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21
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Gao F, Zhou X, Shi J, Luo Y, Tan Y, Fu H, Lai X, Yu J, Huang H, Zhao Y. Eltrombopag treatment promotes platelet recovery and reduces platelet transfusion for patients with post-transplantation thrombocytopenia. Ann Hematol 2020; 99:2679-2687. [PMID: 32519094 DOI: 10.1007/s00277-020-04106-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 05/27/2020] [Indexed: 02/08/2023]
Abstract
Post-transplantation thrombocytopenia (PT) is a common and severe complication which usually leads to poor prognosis. Eltrombopag (EPAG), a novel oral thrombopoietin (TPO) receptor agonist, has shown promising effects in thrombocytopenia due to immune thrombocytopenic purpura (ITP) and refractory severe aplastic anemia (rSAA), while the effectiveness of EPAG for PT patients still needs to be evaluated. A total of 32 PT patients receiving EPAG were retrospectively analyzed between September 2017 and July 2019, including 15 patients with poor graft function (PGF) and 17 patients with secondary failure of platelet recovery (SFPR). To date, 21 (65.6%) patients achieved overall recovery (OR) and 14 (43.8%) patients achieved complete recovery (CR). Among responders, 18 (85.7%) patients discontinued or tapered the drug and 16 (76.2%) patients successfully maintained their best response. During the EPAG treatment, responders received much lower median platelet transfusion units than non-responders (11 vs. 95, P < 0.001). After a median follow-up time of 364 days (range, 24-842), the overall survival in these patients was 78.1% (100% for responders and 36.4% for non-responders, P < 0.001). In the univariate and multivariate analysis, PGF was identified as the independent risk factor for OR (P = 0.041, HR = 5.333). Megakaryocyte (Megk) amounts (P = 0.025, HR = 14.638) and splenomegaly (P = 0.042, HR = 11.278) were identified as independent risk factors for CR. Besides, PGF patients tended to take a longer time to achieve PR and CR than SFPR patients. In conclusion, our data suggest that EPAG can promote platelet recovery and reduce platelet transfusion in PT patients.
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Affiliation(s)
- Fei Gao
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - Xiaoyu Zhou
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - Jimin Shi
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - Yi Luo
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - Yamin Tan
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - Huarui Fu
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - Xiaoyu Lai
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - Jian Yu
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China.,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China
| | - He Huang
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China. .,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China. .,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China.
| | - Yanmin Zhao
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, People's Republic of China. .,Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China. .,Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, Zhejiang, People's Republic of China.
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22
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Vasudevan Nampoothiri R, Kumar R. Eltrombopag: Role in Cytopenias Following Hematopoietic Stem Cell Transplantation. Indian J Hematol Blood Transfus 2020; 36:238-245. [PMID: 32425372 PMCID: PMC7229069 DOI: 10.1007/s12288-019-01194-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/16/2019] [Indexed: 12/22/2022] Open
Abstract
Eltrombopag is a small molecule oral agonist of the thrombopoietin receptor. Initially used for improving thrombocytopenia in chronic immune thrombocytopenia (ITP), it was later found to be efficacious in various other etiologies of thrombocytopenia as well as inherited marrow failure syndromes. Lately, it has been used for thrombocytopenia and poor graft function after allogeneic hematopoietic stem cell transplantation (HSCT) without any severe adverse events. Although prospective evidence of the efficacy is limited, there are increasing reports on the safety and efficacy with Eltrombopag in post HSCT thrombocytopenia and poor graft function. This provides an exciting opportunity for further research to evaluate both efficacy and cost-effectiveness of the use of Eltrombopag in this scenario. Here we review the current evidence on the indications for the use of Eltrombopag in the post allogeneic hematopoietic stem cell transplant setting.
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Affiliation(s)
- Ram Vasudevan Nampoothiri
- Messner Allogeneic Transplant Program, University of Toronto, Princess Margaret Cancer Centre, 610 University Avenue, Toronto, ON M5G 2M9 Canada
| | - Rajat Kumar
- Messner Allogeneic Transplant Program, University of Toronto, Princess Margaret Cancer Centre, 610 University Avenue, Toronto, ON M5G 2M9 Canada
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23
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Cilloni D, Andreani G, Dragani M, De Gobbi M, Saglio G. Synergistic effect of eltrombopag and deferasirox in aplastic anemia: a clinical case and review of the literature. Leuk Lymphoma 2020; 61:234-236. [DOI: 10.1080/10428194.2019.1660969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Daniela Cilloni
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Giacomo Andreani
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Matteo Dragani
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Marco De Gobbi
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Giuseppe Saglio
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
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24
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Fattizzo B, Levati G, Cassin R, Barcellini W. Eltrombopag in Immune Thrombocytopenia, Aplastic Anemia, and Myelodysplastic Syndrome: From Megakaryopoiesis to Immunomodulation. Drugs 2019; 79:1305-1319. [PMID: 31292909 DOI: 10.1007/s40265-019-01159-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Eltrombopag is an orally available thrombopoietin receptor agonist indicated for the treatment of immune thrombocytopenia (ITP). Beyond the effect on megakaryopoiesis, the drug also showed a stimulating effect on the hematopoietic stem cell with consistent clinical efficacy in aplastic anemia (AA) and myelodysplastic syndromes (MDS). Eltrombopag is highly effective in ITP and less so in AA and MDS. This observation underlines the importance of residual normal hematopoiesis, which is maximal in ITP, minimal/absent in AA, and dysregulated in MDS. In ITP, the drug at 50-75 mg daily induced up to 85% responses both in clinical trials and real-life studies, with the possibility of tapering and discontinuation. In AA, eltrombopag at 150 mg daily was effective in about 40% of cases relapsed/refractory to standard immunosuppression or ineligible for bone marrow transplant. In MDS, the drug seems less effective, with responses in about a quarter of patients at various schedules. The efficacy of eltrombopag in ITP, AA, and MDS suggests the existence of common immune-pathological mechanisms in these diseases, including autoimmunity against peripheral blood cells and bone marrow precursors, as well as a possible evolution of one condition into the other. Additional mechanisms of action emerging from the clinical use of eltrombopag include modulation of T-regulatory cells, restoration of Fc-γ receptor balance in phagocytes, and an iron-mobilizing effect. In this review, we analyzed the most recent literature on eltrombopag use and efficacy in patients with ITP, AA, and MDS, exploring the basis for different dosing, combined treatments, and discontinuation in each context.
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Affiliation(s)
- Bruno Fattizzo
- UO Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
| | - Giorgia Levati
- UO Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,University of Milan, Milan, Italy
| | - Ramona Cassin
- UO Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Wilma Barcellini
- UO Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
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25
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Activity of eltrombopag in severe aplastic anemia. Blood Adv 2019; 2:3054-3062. [PMID: 30425070 DOI: 10.1182/bloodadvances.2018020248] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 09/24/2018] [Indexed: 12/22/2022] Open
Abstract
Since the approval of horse antithymocyte globulin (ATG) decades ago, there was a long hiatus in therapies with activity in severe aplastic anemia (SAA). This scenario changed in 2014 when eltrombopag, a thrombopoietin receptor agonist, was approved for SAA after an insufficient response to initial immunosuppressive therapy (IST). The basis for this approval was the observation of single-agent activity of eltrombopag in this patient population, where 40% to 50% recovered blood counts at times involving >1 lineage. The achievement of transfusion independence confirmed the clinical benefit of this approach. Increase in marrow cellularity and CD34+ cells suggested a recovery to a more functioning bone marrow. Further in its development, eltrombopag was associated with standard horse ATG plus cyclosporine in first line, producing increases in overall (at about 90%) and complete response rates (at about 40%) and leading to transfusion independence and excellent survival. Interestingly, best results were observed when all drugs were started simultaneously. The cumulative incidence of clonal cytogenetic abnormalities to date has compared favorably with the vast experience with IST alone in SAA. Longer follow-up will help in define these long-term risks. In this review, the development of eltrombopag in SAA will be discussed.
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26
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Fattizzo B, Cavallaro F, Milesi G, Barcellini W. Iron mobilization in a real life cohort of aplastic anemia patients treated with eltrombopag. Am J Hematol 2019; 94:E237-E239. [PMID: 31172568 DOI: 10.1002/ajh.25550] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 05/30/2019] [Accepted: 06/03/2019] [Indexed: 02/02/2023]
Affiliation(s)
- Bruno Fattizzo
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore PoliclinicoUnità di Ematologia Milano Italy
| | - Francesca Cavallaro
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore PoliclinicoUnità di Ematologia Milano Italy
| | - Giulia Milesi
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore PoliclinicoUnità di Ematologia Milano Italy
| | - Wilma Barcellini
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore PoliclinicoUnità di Ematologia Milano Italy
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27
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Caillon H, Peterlin P, Chevallier P, Guillaume T, Lebourgeois A, Garnier A, Ropert-Bouchet M, Dejoie T. Eltrombopag induces major non-toxic hypersiderraemia. Br J Haematol 2019; 186:365-366. [PMID: 30873599 DOI: 10.1111/bjh.15863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Hélène Caillon
- Department of Biochemistry, Nantes University Hospital, Nantes, France
| | - Pierre Peterlin
- Clinic of Haematology, Nantes University Hospital, Nantes, France
| | | | | | | | - Alice Garnier
- Clinic of Haematology, Nantes University Hospital, Nantes, France
| | | | - Thomas Dejoie
- Department of Biochemistry, Nantes University Hospital, Nantes, France
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28
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Eltrombopag maintains human hematopoietic stem and progenitor cells under inflammatory conditions mediated by IFN-γ. Blood 2019; 133:2043-2055. [PMID: 30803992 DOI: 10.1182/blood-2018-11-884486] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 02/12/2019] [Indexed: 12/15/2022] Open
Abstract
The proinflammatory cytokine interferon-γ (IFN-γ) has been implicated in human hematopoietic stem and progenitor cell (HSPC) depletion in immune-mediated bone marrow failure syndromes. We show that IFN-γ specifically prevents full engagement of thrombopoietin (TPO), a primary positive regulator of HSPC survival, to its receptor (c-MPL) via steric occlusion of the low-affinity binding site, contributing to perturbation of TPO-induced signaling pathways and decreased survival of human HSPCs. Eltrombopag, a synthetic small molecule mimetic of TPO that interacts with c-MPL at a position distinct from the extracellular binding site of TPO, bypasses this inhibition, providing an explanation for its clinical activity in bone marrow failure, despite already elevated endogenous TPO levels. Thus, IFN-γ-mediated perturbation of TPO:c-MPL complex formation and the resulting inhibition of a critical pathway of growth factor cell signaling may represent a general mechanism by which IFN-γ impairs the function of human HSPCs. This understanding could have broad therapeutic implications for various disorders of chronic inflammation.
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29
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Scheinberg P. Activity of eltrombopag in severe aplastic anemia. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2018; 2018:450-456. [PMID: 30504345 PMCID: PMC6245975 DOI: 10.1182/asheducation-2018.1.450] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Since the approval of horse antithymocyte globulin (ATG) decades ago, there was a long hiatus in therapies with activity in severe aplastic anemia (SAA). This scenario changed in 2014 when eltrombopag, a thrombopoietin receptor agonist, was approved for SAA after an insufficient response to initial immunosuppressive therapy (IST). The basis for this approval was the observation of single-agent activity of eltrombopag in this patient population, where 40% to 50% recovered blood counts at times involving >1 lineage. The achievement of transfusion independence confirmed the clinical benefit of this approach. Increase in marrow cellularity and CD34+ cells suggested a recovery to a more functioning bone marrow. Further in its development, eltrombopag was associated with standard horse ATG plus cyclosporine in first line, producing increases in overall (at about 90%) and complete response rates (at about 40%) and leading to transfusion independence and excellent survival. Interestingly, best results were observed when all drugs were started simultaneously. The cumulative incidence of clonal cytogenetic abnormalities to date has compared favorably with the vast experience with IST alone in SAA. Longer follow-up will help in define these long-term risks. In this review, the development of eltrombopag in SAA will be discussed.
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Affiliation(s)
- Phillip Scheinberg
- Division of Hematology, Hospital A Beneficência Portuguesa, Sao Paulo, Brazil
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