How we treat lower-risk myelodysplastic syndromes

Real world efficacy of luspatercept in patients with lower-risk myelodysplastic syndromes/neoplasms (MDS); a single center study in a heavily pretreated cohort

Anemia leads to transfusion dependence and decreases quality of life in LR-MDS patients. Our study retrospectively evaluates the efficacy and safety of luspatercept in the real-world treatment of anemia in LR-MDS, and the impact of patient and disease characteristics on hematologic improvement erythroid (HI-E). Baseline patient and disease characteristics, and transfusion burden (TB) were captured. HI-E was assessed in patients with ≥16 weeks of therapy per IWG 2018 criteria. Luspatercept achieved high rates (58.1%) of transfusion independence (TI) in heavily pretreated LR-MDS patients (median 58.3 weeks). Response was associated with serum EPO <100 mU/ml, but not with any other baseline characteristic. Adverse effects, including shortness of breath, falls, fatigue, and hypertension, precipitated discontinuation in 8%. Eleven percent progressed to HR-MDS or AML. Median overall survival was not reached and did not differ between responders and nonresponders (p=NS).

Low-risk MDS-A spotlight on precision medicine for SF3B1-mutated patients

A deep understanding of the biological mechanisms driving the pathogenesis of myelodysplastic neoplasms (MDS) is essential to develop comprehensive therapeutic approaches that will benefit patient's disease management and quality of life. In this review, we focus on MDS harboring mutations in the splicing factor SF3B1. Clones harboring this mutation arise from the most primitive hematopoietic compartment and expand throughout the entire myeloid lineage, exerting distinct effects at various stages of differentiation. Supportive care, particularly managing anemia, remains essential in SF3B1-mutated MDS. While SF3B1 mutations are frequently linked with ring sideroblasts and iron overload due to impaired erythropoiesis, the current therapeutic landscape fails to adequately address the underlying disease biology, particularly in transfusion-dependent patients, where further iron overload contributes to increased morbidity and mortality. Novel agents such as Luspatercept and Imetelstat have shown promise, but their availability remains restricted and their long-term efficacy is to be investigated. Spliceosome modulators have failed to deliver and inhibitors of inflammatory pathways, including TLR and NF-κB inhibitors, are still under investigation. This scarcity of effective and disease-modifying therapies highlights the unmet need for new approaches tailored to the molecular and genetic abnormalities in SF3B1-mutated MDS. Emerging strategies targeting metabolic mis-splicing (e.g., COASY) with vitamin B5, pyruvate kinase activators, and inhibitors of oncogenic pathways like MYC and BCL-2 represent potential future avenues for treatment, but their clinical utility remains to be fully explored. The current limitations in treatment underscore the urgency of developing novel, more effective therapies for patients with SF3B1-mutated MDS.

WITHDRAWN: Is TGF-β1 And SMAD-7 Expression At Diagnosis Predictive Of Treatment Response In Patients With Low-Risk Myelodysplastic Syndrome?

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Psychometric properties and meaningful change thresholds for the QOL-E instrument in patients with myelodysplastic neoplasms

Background

Myelodysplastic neoplasms (MDS) are characterized by ineffective hematopoiesis, peripheral blood cytopenias, and an increased risk of progression to acute myeloid leukemia. One of the main treatment goals is improving quality of life (QoL), particularly for patients with lower-risk MDS (LR-MDS) who may live longer with compromised QoL. The QOL-E© is a patient-reported outcome (PRO) measure specifically developed to address the lack of a health-related QoL questionnaire for patients with MDS. The objective of this study was to evaluate the psychometric performance of the QOL-E in patients with LR-MDS.

Methods

Data from four clinical trials in MDS (MEDALIST, DARB-MDS, EQoL-MDS, and RevMDS trials) were used to assess construct validity, reliability, and responsiveness. The QOL-E was validated by the European Organization for the Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire - Core 30 (QLQ-C30) and clinical outcomes. It contains 29 items with the first two items assessing the patient's general well-being and the 27 remaining items grouped into six domain scores: physical well-being (QOL-FIS), functional well-being (QOL-FUN), social/family well-being (QOL-SOC), sexual well-being (QOL-SEX), fatigue (QOL-FAT), and MDS-specific disturbances (QOL-MDSS). Additionally, meaningful within-patient change (MWPC) thresholds were determined for the domains and summary scores of the QOL-E using anchor-based analyses, supported by distribution-based analyses.

Results

A total of 458 patients were included in the analyses. The QOL-E domain/summary scores demonstrated acceptable convergent/divergent and known-groups validity. Test-retest reliability and internal consistency was confirmed with intraclass correlation coefficients and Cronbach alpha exceeding 0.70 across most QOL-E domains/summary scores. The QOL-E domains/summary scores, except for QOL-SEX, had an adequate ability to detect change from baseline to Week 24. MWPC thresholds were proposed for all other domains and summary scores.

Conclusion

The study results demonstrate that the QOL-E is generally fit for purpose to assess treatment effects in populations with LR-MDS and the proposed MWPC thresholds can be used to assess within-patient treatment effect on PROs, as assessed by the QOL-E, in future studies.

Imetelstat: a new addition to the therapeutic landscape of lower-risk MDS

ABSTRACT

Anemia is the most prevalent cytopenia in lower-risk myelodysplastic neoplasms (LR-MDS). There is a paucity of drugs for red blood cell transfusion dependence (RBC-TD), and erythropoiesis-stimulating agents (ESAs) are the mainstay of therapy in many centers. Imetelstat, an oligonucleotide telomerase inhibitor, was recently approved for adults with RBC-TD LR-MDS who are ineligible for or failed prior ESA therapy. Although not yet approved worldwide, here we spotlight the current data for imetelstat and where it may fit in the therapeutic landscape of LR-MDS.

A phase 2 clinical trial of luspatercept in non-transfusion-dependent patients with myelodysplastic syndromes

Luspatercept has shown durable clinical efficacy for the treatment of anemia in transfusion-dependent patients with lower-risk myelodysplastic syndromes (LR-MDS). We report the results of a prespecified primary analysis of a phase 2 trial of luspatercept in non-transfusion-dependent (NTD) Japanese patients with anemia due to LR-MDS. Luspatercept (starting dose 1.0 mg/kg) was administered subcutaneously once every 3 weeks. The primary endpoint was the proportion of patients who achieved hematological improvement-erythroid (HI-E) response (≥ 1.5 g/dL increase in hemoglobin level for 8 weeks) without transfusions within the first 24 weeks of treatment. At the primary analysis data cutoff, 21 patients had been enrolled/treated; 17 and 10 patients had completed 24 and 48 weeks of treatment, respectively. HI-E response occurred within 24 weeks in 10 patients (47.6%; 95% confidence interval, 25.7-70.2; P < 0.0001), which was significantly higher than the predefined threshold (10%). By week 48, HI-E response occurred in 12 patients (57.1%) and 17 patients (81.0%) remained NTD. Luspatercept was well tolerated. Three patients (14.3%) had grade 3-4 treatment-related treatment-emergent adverse events. Luspatercept resulted in statistically and clinically significant improvements in hemoglobin levels, and may help delay the need for transfusions in NTD patients with LR-MDS.

Low dose lenalidomide versus placebo in non-transfusion dependent patients with low risk, del(5q) myelodysplastic syndromes (SintraREV): a randomised, double-blind, phase 3 trial

BACKGROUND

Lenalidomide is the standard of care for patients who are transfusion dependent with chromosome 5q deletion (del[5q]) myelodysplastic syndromes. In the SintraREV trial, we aimed to investigate whether an early intervention of low lenalidomide doses for 2 years could delay transfusion dependency in patients with anaemia who were not transfusion dependent.

METHODS

This randomised, double-blind, phase 3 trial, was conducted at 22 sites (University Hospitals) in Spain, France, and Germany. Eligible patients were aged 18 years or older diagnosed with low-risk or intermediate-1-risk del(5q) myelodysplastic syndromes with non-transfusion-dependent anaemia (according to the IPSS), were erythropoietin-stimulating agents naive, and had an ECOG performance status of 2 or less. Patients were randomly assigned (2:1) by means of a telephone system to receive lenalidomide 5 mg daily in 28-day cycles versus placebo for 2 years. The primary endpoint was time to transfusion dependency based on blinded independent central review. Analysis were by intent-to-treat (ITT) and evaluable population. Safety analyses included all participants who received at least one dose of treatment. This trial is registered with ClinicalTrials.gov (NCT01243476) and EudraCT (2009-013619-36) and is complete.

FINDINGS

Between Feb 15, 2010, and Feb 21, 2018, 61 patients were randomly assigned to receive lenalidomide (n=40; two did not receive treatment) or placebo (n=21). The median age was 72·2 (IQR 65·4-81·9) years, 50 (82%) patients were female, and 11 (18%) were male. The median follow-up time was 60·6 (IQR 32·1-73·9) months. Regarding primary endpoint, median time to transfusion dependency was not reached (95% CI not applicable) in the lenalidomide group versus 11·6 months (95% CI 0·00-30·11) in the placebo group (p=0·0027). Lenalidomide significantly reduced the risk of transfusion dependency by 69·8% (hazard ratio 0·302, 95% CI 0·132-0·692; p=0·0046). The most frequent treatment-related adverse event was neutropenia, occurring in 24 (63%) of 38 patients in the lenalidomide group (grade 3 and 4 in 17 [45%] patients and one [3%], respectively) and in four (19%) of 21 patients in the placebo group (grade 3 in one [5%] patient). Thrombocytopenia was detected in seven (18%) of 38 patients receiving lenalidomide (grade 3 in two [5%] patients). Regarding the non-haematological toxicity, skin disorders (rash nine [23%] of 38 patients) were the most frequently described toxicities among patients receiving lenalidomide, being grade 3 in one (3%) of 38 patients. 19 serious adverse events were reported in 13 patients, 18 in the lenalidomide group and one in the placebo group, five of which were potentially related to the study drug. No treatment-related deaths were identified.

INTERPRETATION

An early approach with low doses of lenalidomide across two years delays the time to transfusion dependency and improves the rate and quality of the responses, with a manageable safety profile in patients who are non-transfusion dependent with del(5q) low-risk myelodysplastic syndromes.

FUNDING

Bristol Myers Squibb.

Decitabine cytotoxicity is promoted by dCMP deaminase DCTD and mitigated by SUMO-dependent E3 ligase TOPORS

The nucleoside analogue decitabine (or 5-aza-dC) is used to treat several haematological cancers. Upon its triphosphorylation and incorporation into DNA, 5-aza-dC induces covalent DNA methyltransferase 1 DNA-protein crosslinks (DNMT1-DPCs), leading to DNA hypomethylation. However, 5-aza-dC's clinical outcomes vary, and relapse is common. Using genome-scale CRISPR/Cas9 screens, we map factors determining 5-aza-dC sensitivity. Unexpectedly, we find that loss of the dCMP deaminase DCTD causes 5-aza-dC resistance, suggesting that 5-aza-dUMP generation is cytotoxic. Combining results from a subsequent genetic screen in DCTD-deficient cells with the identification of the DNMT1-DPC-proximal proteome, we uncover the ubiquitin and SUMO1 E3 ligase, TOPORS, as a new DPC repair factor. TOPORS is recruited to SUMOylated DNMT1-DPCs and promotes their degradation. Our study suggests that 5-aza-dC-induced DPCs cause cytotoxicity when DPC repair is compromised, while cytotoxicity in wild-type cells arises from perturbed nucleotide metabolism, potentially laying the foundations for future identification of predictive biomarkers for decitabine treatment.

Myelodysplastic Neoplasms (MDS): The Current and Future Treatment Landscape

Myelodysplastic neoplasms (MDS) are a heterogenous clonal disorder of hemopoietic stem cells characterized by cytomorphologic dysplasia, ineffective hematopoiesis, peripheral cytopenias and risk of progression to acute myeloid leukemia (AML). Our understanding of this disease has continued to evolve over the last century. More recently, prognostication and treatment have been determined by cytogenetic and molecular data. Specific genetic abnormalities, such as deletion of the long arm of chromosome 5 (del(5q)), TP53 inactivation and SF3B1 mutation, are increasingly associated with disease phenotype and outcome, as reflected in the recently updated fifth edition of the World Health Organization Classification of Hematolymphoid Tumors (WHO5) and the International Consensus Classification 2022 (ICC 2022) classification systems. Treatment of lower-risk MDS is primarily symptom directed to ameliorate cytopenias. Higher-risk disease warrants disease-directed therapy at diagnosis; however, the only possible cure is an allogenic bone marrow transplant. Novel treatments aimed at rational molecular and cellular pathway targets have yielded a number of candidate drugs over recent years; however few new approvals have been granted. With ongoing research, we hope to increasingly offer our MDS patients tailored therapeutic approaches, ultimately decreasing morbidity and mortality.

Infectious Complications in Patients with Myelodysplastic Syndromes: A Report from the Düsseldorf MDS Registry

Despite notable advancements in infection prevention and treatment, individuals with hematologic malignancies still face the persistent threat of frequent and life-threatening complications. Those undergoing chemotherapy or other disease-modifying therapies are particularly vulnerable to developing infectious complications, increasing the risk of mortality. Myelodysplastic syndromes (MDS) predominantly affect the elderly, with the incidence rising with age and peaking at around 70 years. Patients with MDS commonly present with unexplained low blood-cell counts, primarily anemia, and often experience varying degrees of neutropenia as the disease progresses. In our subsequent retrospective study involving 1593 patients from the Düsseldorf MDS Registry, we aimed at outlining the incidence of infections in MDS patients and identifying factors contributing to heightened susceptibility to infectious complications in this population.

Treatment Considerations of Myelodysplastic Syndromes/Neoplasms for Pathologists

The diagnosis of myelodysplastic syndromes/neoplasms (MDS) has evolved over the years with the incorporation of genetic abnormalities to establish a diagnosis, their impact on risk stratification, prognostication, and therapeutic options. Hematopathologists are the cornerstone to establish an accurate diagnosis and ensure patients receive the best available treatment option. Hematopathologists and clinicians must work closely together to establish the best disease subclassification, by combining pathologic findings with the clinical presentation. This will ensure patients receive the best therapeutic approach by better understanding the disease entity. In this review, we discuss how we approach a bone marrow biopsy report in the management of MDS.

Classification, risk stratification and response assessment in myelodysplastic syndromes/neoplasms (MDS): A state-of-the-art report on behalf of the International Consortium for MDS (icMDS)

The guidelines for classification, prognostication, and response assessment of myelodysplastic syndromes/neoplasms (MDS) have all recently been updated. In this report on behalf of the International Consortium for MDS (icMDS) we summarize these developments. We first critically examine the updated World Health Organization (WHO) classification and the International Consensus Classification (ICC) of MDS. We then compare traditional and molecularly based risk MDS risk assessment tools. Lastly, we discuss limitations of criteria in measuring therapeutic benefit and highlight how the International Working Group (IWG) 2018 and 2023 response criteria addressed these deficiencies and are endorsed by the icMDS. We also address the importance of patient centered care by discussing the value of quality-of-life assessment. We hope that the reader of this review will have a better understanding of how to classify MDS, predict clinical outcomes and evaluate therapeutic outcomes.

Phase 1 study of JNJ-64619178, a protein arginine methyltransferase 5 inhibitor, in patients with lower-risk myelodysplastic syndromes

Splicing factor (SF) gene mutations are frequent in myelodysplastic syndromes (MDS), and agents that modulate RNA splicing are hypothesized to provide clinical benefit. JNJ-64619178, a protein arginine methyltransferase 5 (PRMT5) inhibitor, was evaluated in patients with lower-risk (LR) MDS in a multi-part, Phase 1, multicenter study. The objectives were to determine a tolerable dose and to characterize safety, pharmacokinetics, pharmacodynamics, and preliminary clinical activity. JNJ-64619178 was administered on a 14 days on/7 days off schedule or every day on a 21-day cycle to patients with International Prognostic Scoring System (IPSS) Low or Intermediate-1 risk MDS who were red blood cell transfusion-dependent. Twenty-four patients were enrolled; 15 (62.5 %) patients had low IPSS risk score, while 18 (75.0 %) had an SF3B1 mutation. Median duration of treatment was 3.45 months (range: 0.03-6.93). No dose limiting toxicities were observed. The 0.5 mg once daily dose was considered better tolerated and chosen for dose expansion. Twenty-three (95.8 %) patients experienced treatment-emergent adverse events (TEAE). The most common TEAEs were neutropenia (15 [62.5 %]) and thrombocytopenia (14 [58.3 %]). JNJ-64619178 pharmacokinetics was dose-dependent. Target engagement as measured by plasma symmetric di-methylarginine was observed across all dose levels; however, variant allele frequency of clonal mutations in bone marrow or blood did not show sustained reductions from baseline. No patient achieved objective response or hematologic improvement per International Working Group 2006 criteria, or transfusion independence. A tolerable dose of JNJ-64619178 was identified in patients with LR MDS. However, no evidence of clinical benefit was observed.

Why do we not have more drugs approved for MDS? A critical viewpoint on novel drug development in MDS

Approval of new agents to treat higher risk (HR) myelodysplastic syndrome (MDS) has stalled since the approval of DNA methyltransferase inhibitors (DNMTi). In addition, the options for patients with lower risk (LR) MDS who have high transfusion needs and do not harbor ring sideroblasts or 5q- syndrome are limited. Here, we review the current treatment landscape in MDS and identify areas of unmet need, such as treatment after failure of erythropoiesis-stimulating agents or DNMTis, TP53-mutated disease, and MDS with potentially targetable mutations. We discuss how our understanding of MDS pathogenesis can inform therapy development, including treating HR-MDS similarly to AML and pursuing therapies to address splicing factor mutations and dysregulated inflammation. We then bring a critical lens to current methodology of MDS studies and propose solutions to improve the efficiency and yield of these clinical trials, including using the most meaningful response metrics and expanding enrollment.

Efficacy and safety of luspatercept versus epoetin alfa in erythropoiesis-stimulating agent-naive, transfusion-dependent, lower-risk myelodysplastic syndromes (COMMANDS): interim analysis of a phase 3, open-label, randomised controlled trial

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) are the standard-of-care treatment for anaemia in most patients with lower-risk myelodysplastic syndromes but responses are limited and transient. Luspatercept promotes late-stage erythroid maturation and has shown durable clinical efficacy in patients with lower-risk myelodysplastic syndromes. In this study, we report the results of a prespecified interim analysis of luspatercept versus epoetin alfa for the treatment of anaemia due to lower-risk myelodysplastic syndromes in the phase 3 COMMANDS trial.

METHODS

The phase 3, open-label, randomised controlled COMMANDS trial is being conducted at 142 sites in 26 countries. Eligible patients were aged 18 years or older, had a diagnosis of myelodysplastic syndromes of very low risk, low risk, or intermediate risk (per the Revised International Prognostic Scoring System), were ESA-naive, and required red blood cell transfusions (2-6 packed red blood cell units per 8 weeks for ≥8 weeks immediately before randomisation). Integrated response technology was used to randomly assign patients (1:1, block size 4) to luspatercept or epoetin alfa, stratified by baseline red blood cell transfusion burden (<4 units per 8 weeks vs ≥4 units per 8 weeks), endogenous serum erythropoietin concentration (≤200 U/L vs >200 to <500 U/L), and ring sideroblast status (positive vs negative). Luspatercept was administered subcutaneously once every 3 weeks starting at 1·0 mg/kg body weight with possible titration up to 1·75 mg/kg. Epoetin alfa was administered subcutaneously once a week starting at 450 IU/kg body weight with possible titration up to 1050 IU/kg (maximum permitted total dose of 80 000 IU). The primary endpoint was red blood cell transfusion independence for at least 12 weeks with a concurrent mean haemoglobin increase of at least 1·5 g/dL (weeks 1-24), assessed in the intention-to-treat population. Safety was assessed in patients who received at least one dose of study treatment. The COMMANDS trial was registered with ClinicalTrials.gov, NCT03682536 (active, not recruiting).

FINDINGS

Between Jan 2, 2019 and Aug 31, 2022, 356 patients were randomly assigned to receive luspatercept (178 patients) or epoetin alfa (178 patients), comprising 198 (56%) men and 158 (44%) women (median age 74 years [IQR 69-80]). The interim efficacy analysis was done for 301 patients (147 in the luspatercept group and 154 in the epoetin alfa group) who completed 24 weeks of treatment or discontinued earlier. 86 (59%) of 147 patients in the luspatercept group and 48 (31%) of 154 patients in the epoetin alfa group reached the primary endpoint (common risk difference on response rate 26·6; 95% CI 15·8-37·4; p<0·0001). Median treatment exposure was longer for patients receiving luspatercept (42 weeks [IQR 20-73]) versus epoetin alfa (27 weeks [19-55]). The most frequently reported grade 3 or 4 treatment-emergent adverse events with luspatercept (≥3% patients) were hypertension, anaemia, dyspnoea, neutropenia, thrombocytopenia, pneumonia, COVID-19, myelodysplastic syndromes, and syncope; and with epoetin alfa were anaemia, pneumonia, neutropenia, hypertension, iron overload, COVID-19 pneumonia, and myelodysplastic syndromes. The most common suspected treatment-related adverse events in the luspatercept group (≥3% patients, with the most common event occurring in 5% patients) were fatigue, asthenia, nausea, dyspnoea, hypertension, and headache; and none (≥3% patients) in the epoetin alfa group. One death after diagnosis of acute myeloid leukaemia was considered to be related to luspatercept treatment (44 days on treatment).

INTERPRETATION

In this interim analysis, luspatercept improved the rate at which red blood cell transfusion independence and increased haemoglobin were achieved compared with epoetin alfa in ESA-naive patients with lower-risk myelodysplastic syndromes. Long-term follow-up and additional data will be needed to confirm these results and further refine findings in other subgroups of patients with lower-risk myelodysplastic syndromes, including non-mutated SF3B1 or ring sideroblast-negative subgroups.

FUNDING

Celgene and Acceleron Pharma.

The burden of red blood cell transfusions in patients with lower-risk myelodysplastic syndromes and ring sideroblasts: an analysis of the prospective MDS-CAN registry

Many patients with lower-risk myelodysplastic syndromes (LR MDS) require long-term red blood cell (RBC) transfusions to manage anemia. The consequences of RBC transfusions in LR MDS with ring sideroblasts (LR MDS-RS) are not well known. We estimated the association between cumulative RBC dose density and clinical and patient-reported outcomes using data from the MDS-CAN registry for patients enrolled between January 2008 and December 2018. Outcomes included overall survival, hospitalization, and health-related quality of life (HRQoL). A total of 145 enrolled patients with LR MDS and RS ≥5% had a median follow-up time of 27.1 months; 45 had no transfusions during follow-up, 51 had <1 transfusion per month, and 49 had ≥1 transfusion per month. The cumulative density of RBC transfusions was associated with significantly greater mortality, hospitalization, and inferior HRQoL, suggesting that exposure to RBC transfusion may constitute a significant treatment burden in patients with LR MDS-RS.

Advances in myelodysplastic syndromes: promising novel agents and combination strategies

INTRODUCTION

Myelodysplastic syndromes (MDS) are heterogeneous group of clonal hematopoietic stem cell neoplasms that have limited approved treatment options. Multiple novel agents are currently being tested in a clinical trial setting. From a therapeutic perspective, MDS is generally divided into lower-risk and higher-risk disease. In this review, we summarize some of the most prominent novel agents currently in development.

AREAS COVERED

This review focuses on select clinical trials in both lower- and higher-risk MDS, elucidating the mechanisms of action and rationale for drug combinations and summarizing early safety and efficacy data using novel agents in MDS.

EXPERT OPINION

Advances in understanding the innate immune system, telomere biology, as well as genomic drivers of the disease have led to the development of multiple novel agents that are currently in late stages of clinical development in MDS. Imetelstat is being tested in lower-risk disease and the phase III clinical trial recently completed accrual. Magrolimab, sabatolimab, and venetoclax in addition to novel oral hypomethylating agents (HMA) are being investigated in higher-risk MDS. These advances will hopefully bring better treatment options to patients and lead to a shift in the treatment paradigm. Post HMA therapy remains an area of dire unmet need.

A natural history of lower-risk myelodysplastic syndromes with ring sideroblasts: an analysis of the MDS-CAN registry

Patients with lower-risk (LR) myelodysplastic syndromes (MDS) with ring sideroblasts (RS) have better prognosis than those without RS, but how they fare over time is not fully understood. This study's objective was to assess the natural history of LR MDS with RS ≥5% using MDS-CAN registry individual data. Kaplan-Meier estimates and generalized linear mixed models were used to describe time-to-event outcomes and continuous outcomes, respectively. One hundred and thirty-eight patients were enrolled; median times from diagnosis to enrollment and follow-up were 6.6 and 39.6 months, respectively. Within 5 years of enrollment, 65% of patients had ≥1 red blood cell transfusion dependence episode. Within 5 years of diagnosis, 59% developed iron overload, 38% received iron chelation therapy, 14% progressed to acute myeloid leukemia, and 42% died. Patients exhibited inferior health-related quality of life trends. These first real-world data in LR MDS-RS in Canada indicate a high level of morbidity and mortality over a 5-year period. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT02537990.

Long-Term Efficacy and Safety of Luspatercept for Anemia Treatment in Patients With Lower-Risk Myelodysplastic Syndromes: The Phase II PACE-MDS Study

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Luspatercept has high clinical activity in patients with transfusion-dependent lower-risk myelodysplastic syndromes (LR-MDS) and ring sideroblasts (RS) relapsed or refractory to erythropoietin. We report long-term luspatercept safety and efficacy in 108 patients with LR-MDS in the PACE-MDS study, including 44 non-RS and 34 non-transfusion-dependent or previously untreated patients. The primary end point was safety. Secondary end points included rates of hematologic improvement (HI) erythroid (HI-E), HI neutrophil, and HI platelet. Exploratory end points included erythropoiesis biomarker quantitation and mutation data. Median duration of luspatercept exposure was 315 days (range, 21-1,934 days). No new safety signals emerged. HI-E was observed in 53.7% of patients, including 36.4% of non-RS and 70.6% of non-transfusion-dependent patients. HI neutrophil and HI platelet were observed in 33.3% and 9.5% of patients, respectively. An almost three-fold increase in bone marrow late to early progenitor cell ratio accompanied HI-E response, irrespective of RS status. Lower baseline erythropoietin levels in non-RS patients (69.6 v 623.3 IU/L; P = .0077) and higher late to early erythroid progenitor cell ratio (10.44 v 4.48; P = .0106) in RS patients were associated with HI-E. This study highlights luspatercept's effects across LR-MDS subtypes, including untreated MDS-RS, serving as a platform for future trials.

Myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a family of myeloid cancers with diverse genotypes and phenotypes characterized by ineffective haematopoiesis and risk of transformation to acute myeloid leukaemia (AML). Some epidemiological data indicate that MDS incidence is increasing in resource-rich regions but this is controversial. Most MDS cases are caused by randomly acquired somatic mutations. In some patients, the phenotype and/or genotype of MDS overlaps with that of bone marrow failure disorders such as aplastic anaemia, paroxysmal nocturnal haemoglobinuria (PNH) and AML. Prognostic systems, such as the revised International Prognostic Scoring System (IPSS-R), provide reasonably accurate predictions of survival at the population level. Therapeutic goals in individuals with lower-risk MDS include improving quality of life and minimizing erythrocyte and platelet transfusions. Therapeutic goals in people with higher-risk MDS include decreasing the risk of AML transformation and prolonging survival. Haematopoietic cell transplantation (HCT) can cure MDS, yet fewer than 10% of affected individuals receive this treatment. However, how, when and in which patients with HCT for MDS should be performed remains controversial, with some studies suggesting HCT is preferred in some individuals with higher-risk MDS. Advances in the understanding of MDS biology offer the prospect of new therapeutic approaches.

Efficacy and Safety of Luspatercept in the Treatment of β-Thalassemia: A Systematic Review

β-thalassemia is characterized by the faulty generation of hemoglobin resulting in an elevated α/β globin ratio; this led to several patients needing red blood cell (RBC) transfusions for the rest of their lives. Luspatercept is an erythroid maturation test for treating various types of anemia, including β-thalassemia. It inhibits the Smad2/3 cascade and treats β-thalassemia by downregulating the transforming growth factor-beta (TGF-β) pathway. Luspatercept was evaluated in randomized controlled trials (RCTs). However, there is still limited data. Therefore, the study aims to review the current literature to assess the efficacy of luspatercept in cure β-thalassemia and its safety. From 2015 to 2022, searches were undertaken in PubMed, Google Scholar, and Cochrane. Only RCTs published in English were eligible for inclusion. The Cochrane Collaboration tool for bias assessment was used to analyze the quality of the publications. Our search strategy revealed 94 publications, of which 12 full-text papers were read and five were chosen for this review.All five trials included 1161 participants. Of whom, 153 (13.18%) entered phase 2, and 1008 (86.82%) entered phase 3. Two articles included 153 participants, of whom 70 (45.75%) were transfusion-dependent beta-thalassemia (TD) and 83 (54.25%) were non-transfusion-dependent beta-thalassemia (NTD) of phase 2. Three articles included 1008 participants, of whom 672 (66.67%) were given luspatercept and 336 (33.33%) were given a placebo. All participants in RCTs were 18 years of age or older. In phase 2, 0.2 to 1.25 mg/kg of luspatercept was given, and in phase 3, 1.0 to 1.25 mg/kg of luspatercept was given once every three weeks. In beta-thalassemia patients, luspatercept was more effective than a placebo and well tolerated. The high dose has shown promising results in the erythroid response, measured by a drop in blood transfusions or an average rise in hemoglobin levels. Luspatercept might make patients less likely to need RBC transfusions, improve their clinical results, and improve their quality of life. Adverse events were hyperuricemia, arthralgia, dizziness, influenza hypertension, and bone pain, but they were manageable.

SF3B1 Mutations in Hematological Malignancies

Recently, mutations in the genes involved in the spliceosome have attracted considerable interest in different neoplasms. Among these, SF3B1 mutations have acquired great interest, especially in myelodysplastic syndromes, as they identify a subgroup of patients who can benefit from personalized therapy. The SF3B1 gene encodes the largest subunit of the splicing factor 3b protein complex and is critical for spliceosome assembly and mRNA splicing. The mutated SF3B1 gene encodes for a protein with a different mRNA processing mechanism that results in the aberrant splicing of many mRNAs, which can be downregulated. Although there are many mRNAs affected by a splicing alteration, only a few of these have been directly related to the pathogenesis of several diseases. In this review, we took a snapshot of the current knowledge on the implications of SF3B1 mutations in different hematological malignancies.

The development of pevonedistat in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML): hope or hype?

Myelodysplastic syndrome (MDS) is a clonal hematopoietic stem cell disorder clinically defined by cytopenias, bone marrow failure, and an increased risk of progressing to acute myeloid leukemia (AML). Traditionally, first-line treatment for patients with higher-risk MDS has been hypomethylating agents (HMAs). However, these agents have modest clinical activity as single agents. A one-size-fits-all treatment paradigm is insufficient for such a heterogeneous disease in the modern era of precision medicine. Several new agents have been developed for MDS with the hopes of improving clinical outcomes and survival. Pevonedistat is a first-in-class, novel inhibitor of neuronal precursor cell-expressed developmentally down-regulated protein-8 (NEDD8) activating enzyme (NAE) blocking the neddylation pathway leading to downstream effects on the ubiquitin-proteosome pathway. Pevonedistat ultimately leads to apoptosis and inhibition of the cell cycle in cancer cells. Studies have demonstrated the safety profile of pevonedistat, leading to the development of multiple trials investigating combination strategies with pevonedistat in MDS and AML. In this review, we summarize the preclinical and clinical rationale for pevonedistat in MDS and AML, review the clinical data of this agent alone and in combination with HMAs to date, and highlight potential future directions for this agent in myeloid malignancies.

Historical expectations with DNA methyltransferase inhibitor monotherapy in MDS: when is combination therapy truly "promising"?

DNA methyltransferase inhibitors (DNMTIs) for patients with higher risk myelodysplastic syndromes (HR-MDS) have low complete remission rates and are not curative. Early DNMTI combination clinical trials in HR-MDS are often termed "promising," but many randomized trials subsequently failed to show benefit. Clearer understanding of when a combination is likely to improve upon DNMTI monotherapy would inform randomized studies. We reviewed MDS azacitidine or decitabine monotherapy studies. We collected baseline demographics including International Prognostic Scoring System (IPSS) risk, DNMTI, disease characteristics; and response variables including survival and marrow and hematologic responses. Aggregate estimates across studies were calculated using meta-analyses techniques. Using a binomial design, we estimated the necessary operating characteristics to design a phase 2 study showing improved efficacy of a combination over monotherapy. Among 1908 patients, the overall response rate (ORR) was 24% (n = 464; 95% confidence interval [CI], 0.22-0.26): 267 complete response (CR, 14%), 68 partial response (4%), and 129 marrow complete remission (7%). Among 1604 patients for whom a hematologic response was reported, 476 (30%; 95% CI, 0.27-0.32) reported hematologic improvement (HI). More patients treated with azacitidine achieved HI (38%; 95% CI, 0.35-0.41) compared with decitabine (15%; 95% CI, 0.13-0.19), whereas the marrow ORR rate was higher with decitabine (29%; 95% CI, 0.26-0.33) compared with azacitidine (21%; 95% CI, 0.19-0.23). CR rates were similar between DNMTIs: 13% with azacitidine and 16% with decitabine. Variables that influence MDS response include the specific DNMTI backbone and the distribution of IPSS risk of patients enrolled on a trial. Considering these factors can help identify which early combination approaches are worth assessing in larger randomized trials.

Room for Improvement: A 20-Year Single Center Experience with Allogeneic Stem Cell Transplantation for Myelodysplastic Syndromes

Allogeneic stem cell transplantation (allo-SCT) remains the only curative therapeutic approach for patients with myelodysplastic syndromes (MDS). The aim of the study was to assess the efficacy/safety of allo-SCT as well as to identify factors influencing post-transplant survival. One hundred and two MDS patients (median age: 48 years; 57 males) who underwent allo-SCT were retrospectively evaluated. Twenty seven patients were transplanted from HLA-matched sibling and 75 patients received grafts from unrelated donors. Peripheral blood was a source of stem cell for 79 patients. Reduced intensity conditioning was used in 64 subjects. Acute and chronic graft versus host disease (GvHD) developed in 61 and 19 of patients, respectively. In total, 61 patients have died. The causes of deaths included infectious complications (n = 30), steroid-resistant GvHD (n = 17), MDS relapse (n = 9) and transformation to AML (n = 5). Non-relapse mortality and cumulative incidence of relapse at 2 years were 49.8% and 9%, respectively. 41 patients are alive at last contact and present full donor chimerism. 38 patients remain in complete hematological remission (CHR), 3 patients had CHR with incomplete platelet recovery. Median follow-up from diagnosis of MDS and transplantation are 27.1 months and 7 months respectively. Overall survival and relapse-free survival were 41% at 2 years. Increased serum ferritin level > 1000 ng/ml, presence of acute GvHD, grades III–IV acute GvHD and high hematopoietic cell transplantation-comorbidity index were found to negatively influenced survival. Allo-SCT for MDS is feasible procedure with a proportion of patients to be cured.

Mitochondrial Fragmentation Triggers Ineffective Hematopoiesis in Myelodysplastic Syndromes

Ineffective hematopoiesis is a fundamental process leading to the pathogenesis of myelodysplastic syndromes (MDS). However, the pathobiological mediators of ineffective hematopoiesis in MDS remain unclear. Here, we demonstrated that overwhelming mitochondrial fragmentation in mutant hematopoietic stem cells and progenitors (HSC/Ps) triggers ineffective hematopoiesis in MDS. Mouse modeling of CBL exon-deletion with RUNX1 mutants, previously unreported co-mutations in MDS patients, recapitulated not only clinically relevant MDS phenotypes but also a distinct MDS-related gene signature. Mechanistically, dynamin-related protein 1 (DRP1)-dependent excessive mitochondrial fragmentation in HSC/Ps led to excessive ROS production, induced inflammatory signaling activation, and promoted subsequent dysplasia formation and impairment of granulopoiesis. Mitochondrial fragmentation was generally observed in patients with MDS. Pharmacological inhibition of DRP1 attenuated mitochondrial fragmentation and rescued ineffective hematopoiesis phenotypes in MDS mice. These findings provide mechanistic insights into ineffective hematopoiesis and indicate that dysregulated mitochondrial dynamics could be a therapeutic target for bone marrow failure in MDS.

Luspatercept as a therapy for myelodysplastic syndromes with ring sideroblasts

INTRODUCTION

Myelodysplastic syndromes (MDS) are a heterogeneous group of hematopoietic stem cell diseases characterized by cell dysplasia, ineffective hematopoiesis and risk of transformation to acute myeloid leukemia (AML). The median age of 75 years at diagnosis is associated with the presence of comorbidities, which preclude intensive therapies like allogeneic hematopoietic stem cell transplantation in most MDS patients. Risk stratification using the (Revised) International Prognostic Scoring System (IPSS/IPSS-R) is necessary to plan individualized treatment.

AREAS COVERED

Luspatercept (ACE-536), a specific activin receptor fusion protein, promotes late-stage erythropoiesis. Two clinical trials, PACE-MDS (phase 2) and MEDALIST (phase 3), yielded positive results in terms of improved hemoglobin levels and loss of transfusion dependence, with hardly any side effects. A phase 3 trial to compare luspatercept to ESAs (COMMANDS study) is ongoing.

EXPERT OPINION

Luspatercept is a promising alternative to ESAs for a subset of transfusion-dependent patients with lower risk MDS, namely those with a sideroblastic phenotype who are either not suitable for or have already failed erythropoietin-based treatment. The favorable safety profile and convenient subcutaneous administration every 3 weeks are more conducive to patients' quality of life than chronic red blood cell transfusion therapy.

Lenalidomide for anemia correction in lower-risk del(5q) myelodysplastic syndrome patients of Asian ethnicity

Background

To estimate real-world outcomes in East Asian populations, we conducted a nationwide retrospective analysis of the efficacy and safety of lenalidomide for del(5q) myelodysplastic syndrome (MDS) patients with transfusion-dependent anemia in Korea.

Methods

Patients aged ≥19 years who had received lenalidomide for the treatment of lower-risk, red blood cell (RBC) transfusion-dependent del(5q) MDS were selected. A filled case report form (CRF) with information from electronic medical records was requested from members of the acute myeloid leukemia (AML)/MDS Working Party of the Korean Society of Hematology. All the CRFs were gathered and analyzed.

Results

A total of 31 patients were included in this study. Of 28 evaluable patients, 19 (67.9%) achieved RBC transfusion independence (RBC-TI). Female sex and the development of thrombocytopenia during treatment were associated with achieving RBC-TI. The most common non-hematologic toxicities were pruritus, fatigue, and rashes. All non-hematologic toxicities of grades ≥3 were limited to rash (12.9%) and pruritus (6.5%). Dose reduction was required in 15 of the 19 responders (78.9%). The most common final stable dosing schedule for the responders was 5 mg once every other day (31.6%).

Conclusion

Lenalidomide efficacy and tolerability were similar in the Asian del(5q) MDS patients and western patients. Dose reduction during treatment was common, but it was not associated with inferior outcomes.

Myelodysplastic Syndromes in the Postgenomic Era and Future Perspectives for Precision Medicine

Simple Summary

With demographic ageing, improved cancer survivorship and increased diagnostic sensitivity, incident cases of patients with Myelodysplastic Syndromes (MDS) are continuously rising, leading to a relevant impact on health care resources. Disease heterogeneity and various comorbidities are challenges for the management of the generally elderly patients. Therefore, experienced physicians and multidisciplinary teams should be involved in the establishment of the correct diagnosis, risk-assessment and personalized treatment plan. Next-generation sequencing allows for early detection of clonal hematopoiesis and monitoring of clonal evolution, but also poses new challenges for its appropriate use. At present, allogeneic hematopoietic stem cell transplantation remains the only curative treatment option for a minority of fit MDS patients. All others receive palliative treatment and will eventually progress, having an unmet need for novel therapies. Targeting compounds are in prospect for precision medicine, however, abrogation of clonal evolution to acute myeloid leukemia remains actually out of reach.

Abstract

Myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal disorders caused by sequential accumulation of somatic driver mutations in hematopoietic stem and progenitor cells (HSPCs). MDS is characterized by ineffective hematopoiesis with cytopenia, dysplasia, inflammation, and a variable risk of transformation into secondary acute myeloid leukemia. The advent of next-generation sequencing has revolutionized our understanding of the genetic basis of the disease. Nevertheless, the biology of clonal evolution remains poorly understood, and the stochastic genetic drift with sequential accumulation of genetic hits in HSPCs is individual, highly dynamic and hardly predictable. These continuously moving genetic targets pose substantial challenges for the implementation of precision medicine, which aims to maximize efficacy with minimal toxicity of treatments. In the current postgenomic era, allogeneic hematopoietic stem cell transplantation remains the only curative option for younger and fit MDS patients. For all unfit patients, regeneration of HSPCs stays out of reach and all available therapies remain palliative, which will eventually lead to refractoriness and progression. In this review, we summarize the recent advances in our understanding of MDS pathophysiology and its impact on diagnosis, risk-assessment and disease monitoring. Moreover, we present ongoing clinical trials with targeting compounds and highlight future perspectives for precision medicine.

Novel spontaneous myelodysplastic syndrome mouse model

Background

Myelodysplastic syndrome (MDS) is a group of disorders involving hemopoietic dysfunction leading to leukemia. Although recently progress has been made in identifying underlying genetic mutations, many questions still remain. Animal models of MDS have been produced by introduction of specific mutations. However, there is no spontaneous mouse model of MDS, and an animal model to simulate natural MDS pathogenesis is urgently needed.

Methods

In characterizing the genetically diverse mouse strains of the Collaborative Cross (CC) we observed that one, designated JUN, had abnormal hematological traits. This strain was thus further analyzed for phenotypic and pathological identification, comparing the changes in each cell population in peripheral blood and in bone marrow.

Results

In a specific-pathogen free environment, mice of the JUN strain are relatively thin, with healthy appearance. However, in a conventional environment, they become lethargic, develop wrinkled yellow hair, have loose and light stools, and are prone to infections. We found that the mice were cytopenic, which was due to abnormal differentiation of multipotent bone marrow progenitor cells. These are common characteristics of MDS.

Conclusions

A mouse strain, JUN, was found displaying spontaneous myelodysplastic syndrome. This strain has the advantage over existing models in that it develops MDS spontaneously and is more similar to human MDS than genetically modified mouse models. JUN mice will be an important tool for pathogenesis research of MDS and for evaluation of new drugs and treatments.

Development of luspatercept to treat ineffective erythropoiesis

Luspatercept (Reblozyl) was recently approved for treating patients with transfusion-dependent lower-risk myelodysplastic syndrome (MDS) with ring sideroblasts (RS) and/or SF3B1 mutation who were not eligible for erythropoiesis-stimulating agents (ESAs) or patients for whom those agents failed. Luspatercept acts as an activin receptor type IIB fusion protein ligand trap that targets the altered transforming growth factor beta pathway in MDS, which is associated with impaired terminal erythroid maturation. Treatment with luspatercept results in decreased SMAD signaling, which enables erythroid maturation by means of late-stage erythroblast differentiation and thus improves anemia. ESAs, the current standard first-line therapeutic option for anemic lower-risk patients with MDS, also improve red cell parameters mainly by expanding proliferation of early erythroid progenitor cells. However, erythropoietin (EPO) and its receptor (EPO-R) are also required for survival of late-stage definitive erythroid cells, and they play an essential role in promoting proliferation, survival, and appropriate timing of terminal maturation of primitive erythroid precursors. Thus, luspatercept joins the mechanism of ESAs in promoting erythroid maturation. Especially in the subgroup of MDS patients with RS, luspatercept showed high clinical activity for the treatment of anemia in the phase 2 (PACE-MDS) trial and subsequently in the phase 3 (MEDALIST) trial, which resulted in approval by both the US Food and Drug Administration and the European Medicines Agency in April 2020. Additional studies are needed to better understand the mechanism of action and pharmacodynamics of this novel agent in MDS.

Evaluation of Reduced-Dose Decitabine and Azacitidine for Treating Myelodysplastic Syndromes: A Retrospective Study

Background

Hypomethylating agents (HMA) are considered the first-line therapy for high-risk myelodysplastic syndromes (MDS). However, as the efficacy and safety of rational dosing regimens are lacking, we evaluated the effectiveness and safety of reduced-dose azacitidine (AZA) vs. decitabine (DAC) in adult MDS patients.

Material/Methods

This retrospective study was conducted at the Institute of Hematology & Blood Diseases Hospital, for hospitalized MDS patients diagnosed (WHO 2008 classification criteria) from May 2006 to February 2020. These AZA- and DCA-naive patients treated with AZA 100 mg/(m²·day) for 5 days to 7 days or DAC 20 mg/(m²·day) for 3 days to 4 days, or 20 mg/(m²·day) 1 day/week for 3 weeks/month were assessed for treatment responses and adverse events.

Results

Of the 158 enrolled MDS patients, 120 and 38 patients were administered reduced-dose DAC and AZA, respectively. All the patients received a median of 2 treatment cycles. The overall response rates (ORR) were 50.0% and 73.3% in the AZA and DAC groups, respectively (P=0.007). The percentage of platelet transfusion dependence in the AZA group was lower than the DAC group (P=0.026). The multivariate analysis demonstrated that the DAC treatment was a significant factor for improved responses (OR 2.928; 95% CI 1.267–6.896; P=0.012), and the absolute neutrophil count (ANC) was a predictor of the ORR (OR 0.725; 95% CI 0.558–0.898; P=0.008). Neutropenia (P=0.016) and infection (P=0.032) incidences were higher in the DAC group.

Conclusions

The reduced-dose DAC group demonstrated a better response than the AZA group in MDS patients with different prognostic risks. The patients’ pre-treatment ANC was a significant factor associated with the ORR.

Treatment options for lower-risk myelodysplastic syndromes. Where are we now?

Myelodysplastic syndromes (MDS) are a spectrum of clonal stem-cell disorders characterized clinically by bone-marrow failure. Resultant cytopenias are responsible for significant mortality and decreased quality of life in patients with MDS. In patients with low-risk MDS (LR-MDS), anemia is the most common cytopenia and erythropoiesis-stimulating agents (ESA) are usually used as first-line therapy. Those patients who become refractory to ESA have a poor survival. Available treatment options such as lenalidomide, hypomethylating agents, and immunosuppressive therapy can provide some hematologic response among selected subsets of patients, however durable responses are limited, and these agents can carry significant adverse effects. Chronic transfusions help to alleviate symptoms of anemia but still carry risks associated with transfusion and iron overload. Luspatercept, recently approved for those LR-MDS with ring sideroblasts refractory to ESA, was found to have an improvement in transfusion independence with a well-tolerated safety profile. While anemia is the most common cytopenia, thrombocytopenia and neutropenia management is challenging and the co-occurrence of these cytopenias with anemia may dictate the choice of therapy. In this article, we review LR-MDS and discuss the optimal use of current treatment options and explore new therapeutic options on the horizon.

Patient stratification in myelodysplastic syndromes: how a puzzle may become a map

Heterogeneity is the disease-defining epithet of myelodysplastic syndromes (MDS), a clonal disorder of hematopoietic stem and progenitor cells. During the last decade, significant progress has been made to better understand the diversity of clinical, molecular, cellular, and immunological factors that are bound to the prognosis and outcomes of patients with MDS. Despite the rapid generation of all of this biological information, how to implement it has fallen short. Redefining clinical tools to use this new information remains a challenge. The holistic integration of novel, high-impact individual risk parameters such as patient-reported outcomes or mutational and immunological data into conventional risk stratification systems may further refine patient subgroups, improve predictive power for survival, and provide a next-generation classification and prognosis system for patients with MDS. Dichotomic treatment strategies in patients with MDS according to their patient and disease profiles highlight the importance of precise risk stratification, which may be complemented by the definition of granular cohorts of patients with myeloid neoplasms and a druggable target (ie, IDH1/2 mutations) across conventional blast thresholds.

Eltrombopag monotherapy can improve hematopoiesis in patients with low to intermediate risk-1 myelodysplastic syndrome

Myelodysplastic syndromes (MDS) are a group of clonal myeloid disorders characterized by low blood counts and a propensity to develop acute myeloid leukemia. The management of lowerrisk (LR) MDS with persistent cytopenias remains suboptimal. Eltrombopag, a thrombopoietin-receptor agonist, can improve platelet counts in LR-MDS and trilineage hematopoiesis in aplastic anemia. We conducted a phase II dose modification study to investigate the safety and efficacy of eltrombopag in LR-MDS. The eltrombopag dose was escalated from 50 mg/day to a maximum of 150 mg/day over a period of 16 weeks. The primary efficacy endpoint was hematologic response at 16-20 weeks. Eleven of 25 (44%) patients responded; five and six patients had uni- or bi-lineage hematologic responses, respectively. The predictors of response were presence of a paroxysmal nocturnal hemoglobinuria clone, marrow hypocellularity, thrombocytopenia, and elevated plasma thrombopoietin levels at study entry. The safety profile was consistent with that found in previous eltrombopag studies in aplastic anemia; no patients discontinued the drug due to adverse events. Three patients developed reversible grade 3 liver toxicity and one patient had increased reticulin fibrosis. Ten patients discontinued eltrombopag after achieving a robust response (median time 16 months); four of them reinitiated eltrombopag because of declining blood counts, and all attained a second robust response. Six patients had disease progression not associated with expansion of mutated clones and no patient progressed to develop acute myeloid leukemia on study. In conclusion, eltrombopag was well-tolerated and effective in restoring hematopoiesis in some patients with low or intermediate-1 risk MDS. This study was registered at clinicaltrials.gov as #NCT00932156.

Outcome of allogeneic hematopoietic stem cell transplantation for hypoplastic myelodysplastic syndrome

The prognosis of patients with hypoplastic myelodysplastic syndrome (hMDS) after receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains unclear. This study aimed to evaluate the outcomes of patients with hMDS after allo-HSCT. Between September 2013 and October 2019, a total of 20 consecutive patients with hMDS and 1 patient with clonal cytopenia of undermined significance (CCUS) who underwent allo-HSCT, which included procedures with 9 matched sibling donors, 2 matched unrelated donors, 4 mismatched unrelated donors and 6 haploidentical donors, were enrolled in this study. The median time for myeloid engraftment was 11 days (range 9-17 days), and that for platelet engraftment was 10 days (range 7-17 days). The cumulative incidence (CI) of myeloid and platelet recovery was 95.2 ± 6.0% and 90.5 ± 7.3%, respectively. The CI rates were 40.0 ± 11.3% for grades II-III acute graft-versus-host disease (GVHD), 36.8 ± 11.5% for chronic GVHD and 23.8 ± 9.6% for nonrelapse mortality. No patients experienced relapse. Sixteen surviving patients were followed up for a median of 1113 days (range 110-2305 days), and the overall survival and relapse-free survival rates were both 72.7 ± 10.6%. This limited retrospective analysis suggests that patients with hMDS had a favorable survival after allo-HSCT.

Controversies on the Consequences of Iron Overload and Chelation in MDS

Many patients with MDS are prone to develop systemic and tissue iron overload in part as a consequence of disease-immanent ineffective erythropoiesis. However, chronic red blood cell transfusions, which are part of the supportive care regimen to correct anemia, are the major source of iron overload in MDS. Increased systemic iron levels eventually lead to the saturation of the physiological systemic iron carrier transferrin and the occurrence of non-transferrin-bound iron (NTBI) together with its reactive fraction, the labile plasma iron (LPI). NTBI/LPI-mediated toxicity and tissue iron overload may exert multiple detrimental effects that contribute to the pathogenesis, complications and eventually evolution of MDS. Until recently, the evidence supporting the use of iron chelation in MDS was based on anecdotal reports, uncontrolled clinical trials or prospective registries. Despite not fully conclusive, these and more recent studies, including the TELESTO trial, unravel an overall adverse action of iron overload and therapeutic benefit of chelation, ranging from improved hematological outcome, reduced transfusion dependence and superior survival of iron-loaded MDS patients. The still limited and somehow controversial experimental and clinical data available from preclinical studies and randomized trials highlight the need for further investigation to fully elucidate the mechanisms underlying the pathological impact of iron overload-mediated toxicity as well as the effect of classic and novel iron restriction approaches in MDS. This review aims at providing an overview of the current clinical and translational debated landscape about the consequences of iron overload and chelation in the setting of MDS.

Novel combinations to improve hematopoiesis in myelodysplastic syndrome

Myelodysplastic syndrome (MDS) represents a heterogeneous group of clonal hematopoietic disorders, which is characterized by cytopenias in the peripheral blood and bone marrow dysplasia due to ineffective hematopoiesis. Patients with MDS have an increased risk of transformation to acute myeloid leukemia (AML). Although the molecular basis of MDS is heterogeneous, several studies demonstrated the significant contribution of the dysregulated immune system in accelerating MDS progression. The immunosuppressive tumor microenvironment is shown to induce tolerance of MDS blasts, which may result in a further accumulation of genetic aberrations and lead to the disease progression. Increasing evidence shows an expansion of myeloid-derived suppressor cells (MDSCs), a population of inflammation-associated immature cells, in patients with MDS. Interestingly, the increased MDSC populations are shown to be correlated with a risk of disease progression in MDS. In addition, MDS is highly prevalent in aged individuals with non-hematology co-morbidities who are fragile for chemotherapy. Increasing research effort is devoting to identify novel agents to specific targeting of the MDSC population for MDS treatment.

A 4-gene leukemic stem cell score can independently predict the prognosis of myelodysplastic syndrome patients

Myelodysplastic syndrome (MDS) comprised a heterogeneous group of diseases. The prognosis of patients varies even in the same risk groups. Searching for novel prognostic markers is warranted. Leukemic stem cells (LSCs) are responsible for chemoresistance and relapse in leukemia. Recently, expressions of 17 genes related to stemness of LSCs were found to be associated with prognosis in acute myeloid leukemia patients. However, the clinical impact of LSC genes expressions in MDS, a disorder arising from hematopoietic stem cells, remains unclear. We analyzed expression profile of the 17 stemness-related genes in primary MDS patients and identified expression of 4 genes (LAPTM4B, NGFRAP1, EMP1, and CPXM1) were significantly correlated with overall survival (OS). We constructed an LSC4 scoring system based on the weighted sums of the expression of 4 genes and explored its clinical implications in MDS patients. Higher LSC4 scores were associated with higher revised International Prognostic Scoring System (IPSS-R) scores, complex cytogenetics, and mutations in RUNX1, ASXL1, and TP53. High-score patients had significantly shorter OS and leukemia-free survival (LFS), which was also confirmed in 2 independent validation cohorts. Subgroup analysis revealed the prognostic significance of LSC4 scores for OS remained valid across IPSS-R lower- and higher-risk groups. Furthermore, higher LSC4 score was an independent adverse risk factor for OS and LFS in multivariate analysis. In summary, LSC4 score can independently predict prognosis in MDS patients irrespective of IPSS-R risks and may be used to guide the treatment of MDS patients, especially lower-risk group in whom usually only supportive treatment is given.

Luspatercept in Patients with Lower-Risk Myelodysplastic Syndromes

BACKGROUND

Patients with anemia and lower-risk myelodysplastic syndromes in whom erythropoiesis-stimulating agent therapy is not effective generally become dependent on red-cell transfusions. Luspatercept, a recombinant fusion protein that binds transforming growth factor β superfamily ligands to reduce SMAD2 and SMAD3 signaling, showed promising results in a phase 2 study.

METHODS

In a double-blind, placebo-controlled, phase 3 trial, we randomly assigned patients with very-low-risk, low-risk, or intermediate-risk myelodysplastic syndromes (defined according to the Revised International Prognostic Scoring System) with ring sideroblasts who had been receiving regular red-cell transfusions to receive either luspatercept (at a dose of 1.0 up to 1.75 mg per kilogram of body weight) or placebo, administered subcutaneously every 3 weeks. The primary end point was transfusion independence for 8 weeks or longer during weeks 1 through 24, and the key secondary end point was transfusion independence for 12 weeks or longer, assessed during both weeks 1 through 24 and weeks 1 through 48.

RESULTS

Of the 229 patients enrolled, 153 were randomly assigned to receive luspatercept and 76 to receive placebo; the baseline characteristics of the patients were balanced. Transfusion independence for 8 weeks or longer was observed in 38% of the patients in the luspatercept group, as compared with 13% of those in the placebo group (P<0.001). A higher percentage of patients in the luspatercept group than in the placebo group met the key secondary end point (28% vs. 8% for weeks 1 through 24, and 33% vs. 12% for weeks 1 through 48; P<0.001 for both comparisons). The most common luspatercept-associated adverse events (of any grade) included fatigue, diarrhea, asthenia, nausea, and dizziness. The incidence of adverse events decreased over time.

CONCLUSIONS

Luspatercept reduced the severity of anemia in patients with lower-risk myelodysplastic syndromes with ring sideroblasts who had been receiving regular red-cell transfusions and who had disease that was refractory to or unlikely to respond to erythropoiesis-stimulating agents or who had discontinued such agents owing to an adverse event. (Funded by Celgene and Acceleron Pharma; MEDALIST ClinicalTrials.gov number, NCT02631070; EudraCT number, 2015-003454-41.).

Comparison between 5-day decitabine and 7-day azacitidine for lower-risk myelodysplastic syndromes with poor prognostic features: a retrospective multicentre cohort study

Numerous studies have analysed the clinical efficacies of hypomethylating agents (HMAs) in patients with myelodysplastic syndromes (MDS). However, reports that compare the two HMAs, decitabine and azacitidine, in patients with lower-risk (low and intermediate-1) MDS are limited. We compared 5-day decitabine and 7-day azacitidine regimens in terms of treatment responses, survival outcomes, and adverse events in patients with lower-risk MDS with poor prognostic features. The overall response rates (ORRs) were 67.2% and 44.0% in the patients treated with decitabine and azacitidine, respectively (P = 0.014). While the median progression-free survival (PFS) was significantly better in the patients treated with decitabine than in those treated with azacitidine (P = 0.019), no significant differences in event-free and overall survival rates were observed between the two groups. Multivariate analysis revealed that compared with azacitidine treatment, decitabine treatment is significantly associated with a higher ORR (P = 0.026) and longer PFS (P = 0.037). No significant differences were observed in the incidence of grade 3 or higher haematologic adverse events in response to the two HMAs. In conclusion, in lower-risk MDS, especially with poor prognostic features, ORR and PFS were significantly better with 5-day decitabine treatment than with 7-day azacitidine treatment, with comparable safety.

Enhanced polo-like kinase 1 expression in myelodysplastic syndromes

Background

Cancer is characterized by uncontrolled cellular proliferation, and Polo-like kinase 1 (PLK1), a key regulator of the cell cycle, is overexpressed in many cancers, including acute leukemia and lymphoma. However, the dynamics of PLK1 transcription in myelodysplastic syndromes (MDS) are unknown. This study aimed to investigate the transcript dynamics of PLK1 and determine its role in the pathophysiology of MDS.

Methods

PLK1 mRNA obtained from the bone marrow samples of 67 patients with MDS, 16 patients with secondary acute myeloid leukemia (sAML), and 10 healthy controls were analyzed using quantitative real-time PCR and compared according to various clinical parameters.

Results

The median PLK1 expression levels differed slightly, but not significantly, between MDS and sAML patients [661.21 (range, 29.38-8,987.31) vs. 1,462.05 (32.22-5,734.09), respectively], but were significantly higher (P<0.001) than the levels in the healthy controls [19.0 (1.60-49.90)]. Further analyses of PLK1 levels according to the WHO classification of MDS, prognostic risk groups, karyotype risk groups, marrow blast percentage, and depth of cytopenia did not reveal any significant associations. In patients progressing to sAML, PLK1 expression levels differed significantly according to the presence or absence of resistance to hypomethylation treatment (2,470.58 vs. 415.98, P=0.03).

Conclusion

PLK1 is upregulated in MDS patients; however, its role in the pathophysiology of MDS is unclear. Gene upregulation in cases with pharmacotherapeutic resistance warrants further investigation.

Clinical Outcomes of Decitabine Treatment for Patients With Lower-Risk Myelodysplastic Syndrome on the Basis of the International Prognostic Scoring System

INTRODUCTION

Decitabine has shown clinical benefits in patients with intermediate (INT)-2 or high-risk myelodysplastic syndrome (MDS), determined according to the International Prognostic Scoring System (IPSS), but the benefits have not been well demonstrated in patients with lower-risk (IPSS low or INT-1) disease. Recently, it was proposed that the prognosis for patients with IPSS lower-risk disease is heterogeneous, with a substantial proportion of these patients having poor survival.

PATIENTS AND METHODS

This study included patients with IPSS lower-risk MDS from the DRAMA (An Observational Study for Dacogen Long-Term Treatment in Patients With Myelodysplastic Syndrome; NCT01400633) and DIVA (A Study for Dacogen Treatment in Patients With Myelodysplastic Syndrome; NCT01041846) studies, which were prospective observational studies on the efficacy and safety of decitabine treatment in patients with MDS. Using the Lower-Risk Prognostic Scoring System [LR-PSS], we classified IPSS lower-risk MDS. Patients in each LR-PSS category were divided according to overall response (OR) to decitabine treatment, and survival outcomes were compared.

RESULTS

One hundred sixteen patients were enrolled: LR-PSS category 1 (n = 12; 10.3%), category 2 (n = 56; 48.3%), and category 3 (n = 48; 41.4%). Survival outcomes differed among the 3 categories (P = .046). The overall survival according to OR showed a significant difference in total patients (P = .008) and category 3 patients (P = .003). We analyzed predictive factors for OR, but no variable was found to significantly affect OR.

CONCLUSION

Decitabine treatment showed a survival benefit in the higher-risk group of IPSS lower-risk MDS patients who responded to treatment, and classification using the LR-PSS category was helpful for this subgroup, indicating that decitabine treatment might alter the natural course of disease in these patients.

RBC transfusion independence among lower risk MDS patients receiving hypomethylating agents: a population-level analysis

Most patients with lower risk myelodysplastic syndromes (LR-MDS) become red blood cell (RBC) transfusion dependent at some time during their disease course. Hypomethylating agents (HMAs) are frequently used in this setting; however, reported rates of in RBC transfusion independence (TI) achieved with HMA therapy vary significantly between studies. Here we study the real-life clinical effectiveness of HMA in inducing RBC TI in anemic LR-MDS patients using the Surveillance, Epidemiology and End Results (SEER)-Medicare database. We find that approximately 40% of LR-MDS patients who were receiving RBC transfusions and 33% who were dependent on RBC transfusions at HMA initiation ultimately achieved TI. The receipt of ≥3 transfusions in the 8-week period before HMA initiation was significantly associated with lower odds of achieving TI. Our study provides important population level estimates of clinical effectiveness of HMAs in LR-MDS.

Use of immunosuppressive therapy for management of myelodysplastic syndromes: a systematic review and meta-analysis

Immunosuppressive therapy (IST) is one therapy option for treatment of patients with lower-risk myelodysplastic syndromes (MDS). However, the use of several different immunosuppressive regimens, the lack of high-quality studies, and the absence of validated predictive biomarkers pose important challenges. We conducted a systematic review and meta-analysis according to the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines and searched MEDLINE via PubMed, Ovid EMBASE, COCHRANE registry of clinical trials (CENTRAL), and the Web of Science without language restriction from inception through September 2018, as well as relevant conference proceedings and abstracts, for prospective cohort studies or clinical trials investigating IST in MDS. Fixed and Random-effects models were used to pool response rates. We identified nine prospective cohort studies and 13 clinical trials with a total of 570 patients. Overall response rate was 42.5% [95% confidence interval (CI): 36.1-49.2%] including a complete remission rate of 12.5% (95%CI: 9.3-16.6%) and red blood cell transfusion independence rate of 33.4% (95% CI: 25.1-42.9%). The most commonly used forms of IST were anti-thymocyte globulin alone or in combination with cyclosporin A with a trend towards higher response rates with combination therapy. Progression rate to acute myeloid leukemia was 8.6% per patient year (95%CI: 3.3-13.9%). Overall survival and adverse events were only inconsistently reported. We were unable to validate any biomarkers predictive of a therapeutic response to IST. IST for treatment of lower-risk MDS patients can be successful to alleviate transfusion burden and associated sequelae.

Transforming growth factor (TGF)-β pathway as a therapeutic target in lower risk myelodysplastic syndromes

The transforming growth factor (TGF)-β superfamily comprises more than 30 soluble growth factors that play a central role in erythropoiesis and are part of a tightly regulated myelosuppressive negative feedback loop under physiologic conditions. TGF-β receptor activation and phosphorylation trigger a regulatory circuit of activating and inhibitory SMAD proteins and increased activation of the TGF-β signaling pathway either by a loss of negative feedback or constitutive activation has been associated with the myelosuppression and ineffective erythropoiesis in myelodysplastic syndromes (MDS). Anemia is the predominant cause of morbidity and quality of life impairment in patients with lower-risk (LR)-MDS, and there are very limited therapy options for these patients after failure of erythropoiesis stimulating agents (ESAs). Targeting the aberrant TGF-ß signaling pathway has therefore been investigated as a promising therapeutic approach to resolve the ineffective erythropoiesis in LR-MDS. In this article, we provide a brief overview of the TGF-β signaling cascade in hematopoiesis under physiologic conditions and its role in MDS pathogenesis. We also review preclinical and clinical data for the activin receptor type IIA ligand traps sotatercept and luspatercept that have recently shown promising results in overcoming the myelosuppressive effects of TGF-β signaling alterations to improve hematopoiesis in transfusion-dependent, non-del(5q) LR-MDS patients. Additional potential targets within the TGF-β pathway have also been identified in preclinical experiments and may provide further therapeutic options. Finally, combining different TGF-β pathway inhibitors or using them in combination with ESAs or the immunomodulator lenalidomide might have synergistic effects as well.

Epoetin alfa for the treatment of myelodysplastic syndrome-related anemia: A review of clinical data, clinical guidelines, and treatment protocols

Myelodysplastic syndromes (MDS) are characterized by ineffective hematopoiesis, leading to hematopoietic precursor cell apoptosis and peripheral blood cytopenias. Anemia is the most frequently experienced cytopenia and is the main cause of MDS symptoms, with fatigue and dyspnea contributing to reduced quality of life and increased morbidity. As MDS disease course and prognosis is influenced by disease factors, prognostic scoring systems have been developed for MDS to aid clinical and therapeutic decisions following diagnosis. Erythropoiesis- stimulating agents (ESAs) have been used for many years to treat anemia in patients with lower-risk MDS without chromosomal abnormalities. The use of ESAs is recommended by international clinical practice guidelines, due to the large body of evidence demonstrating their effectiveness in lower-risk MDS. In March 2017, the European Medicines Agency approved epoetin alfa for the treatment of anemia in lower-risk MDS patients, based on the results from a Phase 3 clinical trial and three European registry studies. The effectiveness of biosimilar epoetin alfa (Binocrit^®, Sandoz) to correct anemia in lower-risk MDS patients has also been demonstrated in a retrospective, single-center, observational study. The recent approval of epoetin alfa by the EMA in this setting will provide clinicians with a welcome, approved treatment option for lower-risk MDS.