Ivosidenib induces deep durable remissions in patients with newly diagnosed IDH1-mutant acute myeloid leukemia

Investigation into biased signaling, glycosylation, and drug vulnerability of acute myeloid leukemia

Understanding and harnessing biased signaling offers significant potential for developing novel therapeutic strategies or enhancing existing treatments. By managing biased signaling, it is possible to minimize adverse effects, including toxicity, and to optimize therapeutic outcomes by selectively targeting beneficial pathways. In the context of acute myeloid leukemia (AML), a highly aggressive blood cancer characterized by the rapid proliferation of abnormal myeloid cells in the bone marrow and blood, the dysregulation of these signaling pathways, particularly those involving G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs), significantly contributes to disease progression and therapeutic resistance. Traditional therapies for AML often struggle with resistance and toxicity, leading to poor patient outcomes. However, by exploiting the concept of biased signaling, researchers may be able to design drugs that selectively activate pathways that inhibit cancer cell growth while avoiding those that contribute to resistance or toxicity. Glycosylation, a key post-translational modification (PTM), plays a crucial role in biased signaling by altering receptor conformation and ligand-binding affinity, thereby affecting the outcome of biased signaling. Chemokine receptors like CXCR4, which are often overexpressed and heavily glycosylated in AML, serve as targets for therapeutic intervention. By externally inducing or inhibiting specific PTMs, it may be possible to further refine therapeutic strategies, unlocking new possibilities for developing more effective and less toxic treatments. This review highlights the importance of understanding the dynamic relationship between glycosylation and biased signaling in AML, which is essential for the development of more effective treatments and overcoming drug resistance, ultimately leading to better patient outcomes.

Deconvoluting clonal and cellular architecture in IDH-mutant acute myeloid leukemia

Isocitrate dehydrogenase 1/2 (IDH) mutations are early initiating events in acute myeloid leukemia (AML). The complex clonal architecture and cellular heterogeneity in IDH-mutant AML underlies the heterogeneous clinical presentation and outcomes. Integrating single-cell genotyping and transcriptomics, we demonstrate a stem-like and inflammatory phenotype of IDH-mutant AML and identify clone-specific programs associated with NPM1, NRAS, and SRSF2 co-mutations. Furthermore, these clones had distinct responses to treatment with combination IDH inhibitors and chemotherapy, including elimination, reconstitution of myeloid differentiation, or retention within progenitor populations. At relapse after IDH inhibitor monotherapy, we identify upregulated stemness, inflammation, mitochondrial metabolism, and anti-apoptotic factors, as well as downregulated major histocompatibility complex (MHC) class II antigen presentation. At the pre-leukemic stage, we observe upregulation of IDH2-associated pathways, including inflammation. We deliver a detailed phenotyping of IDH-mutant AML and a framework for dissecting contributions of recurrently mutated genes in AML at diagnosis and following therapy, with implications for precision medicine.

Mutant IDH1 cooperates with NPM1c or FLT3ITD to drive distinct myeloid diseases and molecular outcomes

In human acute myeloid leukemia (AML), mutations of isocitrate dehydrogenase-1 (IDH1) often co-occur with NPM1 mutations, and less frequently with FLT3 mutations. To investigate whether the effects of IDH1 mutation differ according to the specific co-occurring mutation, we generated two strains of double knock-in mutant mice. Idh1R132H combined with Npm1c induced overt AML, whereas Idh1R132H plus Flt3ITD resulted in Flt3ITD-driven myelo- or lymphoproliferation that was minimally affected by Idh1R132H and rarely generated AML. Gene expression profiling revealed differences between Idh1R132H;Npm1c cells and Idh1R132H;Flt3ITD cells and suggested altered heme metabolism and immune responses in the former. The profile of Idh1R132H;Npm1c cells corresponded to that of human IDH-mutated AML cells, particularly those resistant to inhibitors of mutant IDH. Compared to treatment with a menin inhibitor, IDH1-targeted therapy of Idh1R132H;Npm1c AML-bearing mice was less efficacious in improving cell differentiation and extending survival. The differential cooperation of Idh1R132H with Npm1c vs. Flt3ITD may have implications for the devising of subtype-specific treatments for human AML.

Analytical Performance of the NCI-myeloMATCH Assay: A Rapid Turnaround Genomic Profiling Assay for Myeloid Disorders

myeloMATCH is a National Cancer Institute (NCI) precision medicine clinical trial initiative to evaluate treatments for acute myeloid leukemia and myelodysplastic syndrome based on a leukemia's diagnostic molecular-genetic profile. The NCI myeloid assay version 2 (NMAv2) uses the Genexus System, an automated platform with <48-hour turnaround from specimen receipt to reporting, to provide harmonized regulatory-compliant use for myeloMATCH across two independent clinical laboratories. Using clinical specimens, cell lines, and contrived reference materials, NMAv2 exhibited 99% sensitivity for 291 known mutations and 100% specificity. High reproducibility detecting all reportable variants was observed, with >98% mean positive percentage agreement and 100% negative percent agreement across six reproducibility assessments. Reproducibility experiments of companion diagnostic biomarkers (1 to 1.5× clinical limit of reporting) showed 100% positive percentage agreement and negative percent agreement. The limit of detection was 0.06% for hotspot single-nucleotide variants, 0.16% for non-hotspot single-nucleotide variants, 0.51% for hotspot insertion/deletions, approximately 1% for non-hotspot insertion/deletions, 0.23% for FLT3-internal tandem duplications, and ≤40 reads at 0.1% tumor content for fusions. Concordance of 99.39% was observed in orthogonal assays testing 76 blinded myeloid specimens in the sensitivity study, and 100% concordance was observed in testing 54 FLT3-internal tandem duplication specimens. The results show that NMAv2 has high specificity, sensitivity, accuracy, and reproducibility, and can rapidly characterize genomic alterations in acute myeloid leukemia and myelodysplastic syndrome.

Fitness assessment in acute myeloid leukemia: recommendations from an expert panel on behalf of the European LeukemiaNet

ABSTRACT

Fitness assessment in patients with acute myeloid leukemia (AML) is critical to deliver the right therapy to the right patient. Although several scoring systems are available to aid in determining fitness, the absence of validation studies has resulted in the lack of universally accepted assessment procedures. This limitation, combined with the increasing availability of novel agents expanding the spectrum of less-intensive options, has introduced additional complexity to the fitness assessment process. In this evolving context, fitness should reflect eligibility for a specific treatment among the several available, rather than a generic binary classification of eligibility for intensive chemotherapy. Moreover, the growing emphasis on patient-centered care, further highlights the importance of integrating quality of life, patient preferences, patient self-reported physical and social functioning status, social support, and early integration of palliative care into the assessment framework. A modern interpretation of fitness assessment should incorporate a comprehensive evaluation that extends beyond traditional clinical and biological disease characteristics. Thus, fitness assessment in patients with AML represents only 1 piece of a larger puzzle, encompassing the patient's overall capacity to sustain and benefit from a specific therapeutic program.

Metabolism and therapeutic response in acute myeloid leukemia with IDH1/2 mutations

Pathogenic variants of isocitrate dehydrogenase 1 and 2 (IDH1/2) genes are present in approximately 20% of acute myeloid leukemia (AML) cases, resulting in the oncometabolite R-2-hydroxyglutarate (R-2-HG). The accumulation of R-2-HG in leukemic cells and in their niche induces epigenetic modifications, profound rewiring of the cellular metabolism, and microenvironmental remodeling. These changes promote cellular differentiation bias, enhancing the survival and proliferation of leukemic cells, and thus playing a pivotal role in leukemogenesis and resistance to standard AML therapy. This review focuses on the different perspectives offered by studying metabolism and resistance to standard treatments in AML with IDH1 or IDH2 pathogenic variants, for the development of new biomarkers and therapeutic solutions.

Meta-analysis of Therapeutic Approaches in Acute Myeloid Leukemia: Unveiling Trends and Predictors of Treatment Response

OBJECTIVE

To elucidate emerging trends and predictors for optimizing treatment strategies for acute myeloid leukemia (AML).

METHOD

A literature search was conducted on PubMed, Embase, Web of Science, and Google Scholar databases. Bias assessment was conducted using Cochrane's risk of bias tool, while statistical analyses were performed using Review Manager and Comprehensive Meta-Analysis software.

RESULTS

We included 44 studies and the pooled results showed that high-dose cytarabine (HDAC) in induction therapy significantly improved the complete remission (CR) rate than standard-dose cytarabine (SDAC) in younger adults but not older adults (OR: 1.29, 95% CI: 1.12-1.49, P =0.0004 and OR: 1.02, 95% CI: 0.80-1.29, P =0.87, respectively). In consolidation therapy, HDAC showed a significant benefit in event-free survival (EFS) over SDAC (RR: 1.30, 95% CI: 1.04-1.62, P =0.02). The pooled analysis also revealed that idarubicin (IDR) was associated with improved CR rates than daunorubicin (DNR) (OR: 1.34, 95% CI: 1.02-1.76, P =0.04). However, the results do not substantiate the claim that IDR is better than mitoxantrone (MTZ) or that DNR is superior to MTZ in inducing CR (OR: 0.88, 95% CI: 0.72-1.08, P =0.22 and OR: 0.85, 95% CI: 0.72-1.01, P =0.06, respectively). The evidence has also shown that the pooled composite complete response (CRc) rates for FLT3 inhibitors such as sorafenib, gilteritinib, and quizartinib were 56%, 31%, and 36%, respectively. The pooled results further showed that the overall CRc for patients receiving IDH inhibitors and immune checkpoint inhibitors were 49.6% (95% CI: 37-63) and 26% (95% CI: 18.7-35), respectively.

CONCLUSION

Chemotherapy, targeted therapy, and immunotherapy are valuable treatment options for AML patients. However, the efficacy of these AML treatments may vary depending on AML status and patient characteristics such as age and cytogenetic risk.

Acute Myeloid Leukemia: 2025 Update on Diagnosis, Risk-Stratification, and Management

DISEASE OVERVIEW

Acute myeloid leukemia (AML) is a bone marrow stem cell cancer that is often fatal despite available treatments. Diagnosis, risk assessment, monitoring, and therapeutic management of AML have changed dramatically in the last decade due to increased pathophysiologic understanding, improved assessment technology, and the addition of at least 12 approved therapies.

DIAGNOSIS

The diagnosis is based on the presence of immature leukemia cells in the blood, and/or bone marrow or less often in extra-medullary tissues. New biological insights have been integrated into recent classification systems.

RISK ASSESSMENT

The European Leukemia Network has published risk classification algorithms for both intensively and non-intensively treated patients based on cytogenetic and on molecular findings. Prognostic factors may differ based on the therapeutic approach.

MONITORING

Our increasing ability to quantify lower levels of measurable residual disease (MRD) potentially allows better response assessment, as well as dynamic monitoring of disease status. The incorporation of MRD findings into therapeutic decision-making is rapidly evolving.

RISK ADAPTED THERAPY

The availability of 12 newly approved agents has been welcomed; however, optimal strategies incorporating newer agents into therapeutic algorithms are debated. The overarching approach integrates patient and caregiver goals of care, comorbidities, and disease characteristics.

A second look at the status quo for secondary acute myeloid leukemia after hypomethylating agents

This editorial highlights the significant clinical challenges and poor outcomes faced by patients with secondary AML after prior hypomethylating agent therapy (HMA-sAML), underscoring the urgent need for novel treatments. The authors emphasize that current standard therapies remain inadequate, calling for clinical trials tailored specifically to address the unique biological complexity and therapeutic resistance observed in this patient population

Navigating acute myeloid leukemia towards better outcomes: Treatment pathways and challenges for patients ineligible for intensive chemotherapy

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy that affects primarily older individuals. Patients ineligible to receive intensive standard chemotherapy followed by consolidation with/without hematopoietic stem cell transplant have a suboptimal prognosis. In recent years, significant advances have been made in the AML field leading to the development of new anti-leukemic approaches, including lower-intensity therapies specifically developed for patients who are ineligible for intensive chemotherapy. As the available options for this hard-to-manage and historically undertreated patient category are increasing, selecting the best treatment for each patient is crucial and ever more challenging. Accordingly, accurate patient evaluation is required to guide this decision-making process. There is currently no consensus on how to evaluate patients' fitness status, and the available tools that were originally developed for this purpose might not be adequate in the setting of the new treatment options. In this review we describe current management of AML patients unfit for intensive chemotherapy, aiming to highlight current challenges and suggest possible strategies for an accurate therapeutic selection. For this purpose, we will first provide an overview of epidemiology and classification of AML, and then move to current anti-leukemic treatments for unfit patients and the tools used for evaluating patient eligibility for a specific treatment. Finally, we will suggest possible measures to improve the management of AML patients in the era of novel lower-intensity regimens.

[Metabolism and therapy in acute myeloid leukemia with isocitrate dehydrogenase 1/2 mutations]

Isocitrate dehydrogenase IDH1 and IDH2, key enzymes in central and energy metabolism, are frequently mutated in acute myeloid leukemia (AML). They catalyze the production of the oncometabolite R-2-hydroxyglurate, which plays a key role in leukemogenesis and relapse of patients after standard AML treatments. Although the recent introduction of selective inhibitors of IDH1 (ivosidenib) and IDH2 (enasidenib) has improved the prognosis of patients with IDH1- and IDH2-mutant AML, several mechanisms of resistance to these treatments have already been identified, including metabolic reprogramming. The study of these mechanisms has opened up new therapeutic opportunities for the monitoring and treatment of patients with this subtype of AML.

Recent Developments in Differentiation Therapy of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is characterized by the clonal expansion of myeloid progenitors blocked at various stages of their differentiation process, and drugs that bypass this differentiation block are therapeutically efficient, as shown by retinoic acid and arsenic trioxide in acute promyelocytic leukemia. However, the successful application of differentiation therapy in APL has not translated into clinical benefit for other non-APL subtypes of AML, in which intensive chemotherapy regimens represent the standard of care. However, the development of molecular studies has led to the identification of therapeutic targets (such as mutated proteins and deregulated pathways) and has led to the generation of a new category of specific pharmacologic agents. Some of these agents, such as inhibitors of mutant isocitrate dehydrogenase (IDH1 and IDH2), lysine-specific demethylase-1 (LSD1), and Menin, have shown the capacity to induce leukemic cell differentiation and with significant therapeutic efficacy.

How I treat secondary acute myeloid leukemia

ABSTRACT

Secondary acute myeloid leukemia (sAML) has traditionally been used to designate any AML disease arising from an antecedent hematologic disorder or after prior cytotoxic or radiation therapy. We now know sAML comprises multiple disease entities with distinct clinical and biological features: AML, myelodysplastic related; myeloproliferative neoplasm-blast phase; and AML post-cytotoxic therapy. These entities largely represent adverse-risk phenotypes with the majority of patients experiencing suboptimal outcomes with standard therapeutic options. Given the aging general population and the increased life span of individuals receiving DNA-damaging agents for other medical conditions, the incidence of these diseases is steadily rising and now comprise ∼25% to 30% of all new AML diagnoses. Despite the plethora of novel agents approved for AML since 2017, many either are not applicable to sAML (ie, lacking a targetable mutation), have limited efficacy, or have not been studied in these specific entities. Furthermore, these patients are underrepresented in clinical trials, and novel therapeutic options are critically needed. Here, we present multiple patient cases exemplifying the new nomenclature and classification of the diseases comprising sAML and highlighting their diverse presentations. We provide our therapeutic approach for each clinical scenario and discuss the challenges of treatment with the currently available armamentarium.

PSPC1 exerts an oncogenic role in AML by regulating a leukemic transcription program in cooperation with PU.1

Acute myeloid leukemia (AML) is an aggressive hematopoietic malignancy characterized by the blockage of myeloid cell differentiation and uncontrolled proliferation of immature myeloid cells. Here, we show that paraspeckle component 1 (PSPC1) is aberrantly overexpressed and associated with poor survival in AML patients. Using human AML cells and mouse models, we demonstrate that PSPC1 is not required for normal hematopoiesis, but it is critical and essential for AML cells to maintain their leukemic characteristics. PSPC1 loss induces robust differentiation, suppresses proliferation, and abolishes leukemogenesis in diverse AML cells. Mechanistically, PSPC1 exerts a pro-leukemia effect by regulating a unique leukemic transcription program via cooperative chromatin binding with PU.1 and activation of tumor-promoting genes, including NDC1, which is not previously implicated in AML. Our findings uncover a unique and crucial role of PSPC1 dependency in AML and highlight its potential as a promising therapeutic target for AML.

Machine learning-based bulk RNA analysis reveals a prognostic signature of 13 cell death patterns and potential therapeutic target of SMAD3 in acute myeloid leukemia

BACKGROUND

Dysregulation or abnormality of the programmed cell death (PCD) pathway is closely related to the occurrence and development of many tumors, including acute myeloid leukemia (AML). Studying the abnormal characteristics of PCD pathway-related molecular markers can provide a basis for prognosis prediction and targeted drug design in AML patients.

METHODS

A total of 1394 genes representing 13 different PCD pathways were examined in AML patients and healthy donors. The upregulated genes were analyzed for their ability to predict overall survival (OS) individually, and these prognostic genes were subsequently combined to construct a PCD-related prognostic signature via an integrated approach consisting of 101 models based on ten machine learning algorithms. RNA transcriptome and clinical data from multiple AML cohorts (TCGA-AML, GSE106291, GSE146173 and Beat AML) were obtained to develop and validate the AML prognostic model.

RESULTS

A total of 214 upregulated PCD-related genes were identified in AML patients, 39 of which were proven to be prognostic genes in the training cohort. On the basis of the average C-index and number of model genes identified from the machine learning combinations, a PCD index was developed and validated for predicting AML OS. A prognostic nomogram was then generated and validated on the basis of the PCD index, age and ELN risk stratification in the Beat AML cohort and the GSE146173 cohort, revealing satisfactory predictive power (AUC values ≥ 0.7). With different mutation patterns, a higher PCD index was associated with a worse OS. The PCD index was significantly related to higher scores for immunosuppressive cells and mature leukemia cell subtypes. As the gene most closely related to the PCD index, the expression of SMAD3 was further validated in vitro. AML cells harboring KMT2A rearrangements were more sensitive to the SMAD3 inhibitor SIS3, and the expression of the autophagy-related molecular marker LC3 was increased in KMT2A-rearranged cell lines after SIS3 monotherapy and combined treatment.

CONCLUSION

The PCD index and SMAD3 gene expression levels have potential prognostic value and can be used in targeted therapy for AML, and these findings can lead to the development of effective strategies for the combined treatment of high-risk AML patients.

Pharmacokinetics and ADME Characterization After Oral and Intravenous Administration of [14C]-Ziftomenib in Healthy Male Participants

Ziftomenib, a potent, selective inhibitor that binds menin at the lysine methyltransferase 2 interaction site, has demonstrated promising clinical activity with manageable toxicity in heavily pretreated patients with acute myeloid leukemia (AML) and nucleophosmin 1 mutations. This phase 1, open-label study characterized the absorption, metabolism, excretion, and bioavailability of ziftomenib in healthy men and comprised two parts. In part A, a single oral dose of ziftomenib 400 mg (containing 250 μCi [14C]-ziftomenib) was given to evaluate routes and rates of elimination, total radioactivity, and other pharmacokinetic parameters. In part B, a single oral dose of ziftomenib 400 mg followed by an intravenous dose of ziftomenib < 100 μg (containing 1 μCi [14C]-ziftomenib) was administered to evaluate absolute bioavailability (both n = 8 patients). A median tmax of 3.5 h and an elimination t1/2 of 61.5 h demonstrated rapid ziftomenib absorption and enabled once-daily dosing. Total radioactivity recovery was 89.7% in feces and 0.5% in urine over 480 h. Absolute bioavailability of 12.9% was observed. Ziftomenib was primarily metabolized by oxidation, N-demethylation, and N-dealkylation, with 19 metabolites recovered in plasma. All metabolites were considered minor (< 10% of total drug-related exposure). Ziftomenib was the most abundant plasma component (> 10% of total drug-related exposure). In conclusion, ziftomenib underwent limited metabolism following absorption and was primarily excreted as unchanged parent drug in feces. Ziftomenib was well tolerated with no new safety concerns in healthy men. Considering the pharmacokinetic profile and manageable safety outcomes, these findings support further clinical investigation of ziftomenib as treatment for AML.

Precision Medicine in Myeloid Neoplasia: Challenges and Opportunities

High-risk myeloid neoplasms encompass a group of hematologic malignancies known to cause significant cytopenias, which are accompanied by the risk of end-organ damage. They tend to have an aggressive clinical course and limit life expectancy in the absence of effective treatments. The adoption of precision medicine approaches has been limited by substantive diversity in somatic mutations, limited fraction of patients with targetable genetic lesions, and the prolonged turnaround times of pertinent genetic tests. Efforts to incorporate targeted agents into first-line treatment, rapidly determine pre-treatment molecular or cytogenetic aberrations, and evaluate functional vulnerabilities ex vivo hold promise for advancing the use of precision medicine in these malignancies. Given the relative accessibility of malignant cells from blood and bone marrow, precision medicine strategies hold great potential to shape future standard-of-care approaches to patients with high-risk myeloid malignancies. This review aims to summarize the development of the targeted therapies currently available to treat these blood cancers, most notably acute myeloid leukemia, and also evaluate future opportunities and challenges related to the integration of personalized approaches.

IDH-mutant gliomas in children and adolescents - from biology to clinical trials

Gliomas account for nearly 30% of all primary central nervous system (CNS) tumors in children and adolescents and young adults (AYA), contributing to significant morbidity and mortality. The updated molecular classification of gliomas defines molecularly diverse subtypes with a spectrum of tumors associated with age-distinct incidence. In adults, gliomas are characterized by the presence or absence of mutations in isocitrate dehydrogenase (IDH), with mutated IDH (mIDH) gliomas providing favorable outcomes and avenues for targeted therapy with the emergence of mIDH inhibitors. Despite their rarity, IDH mutations have been reported in 5-15% of pediatric glioma cases. Those with primary mismatch-repair deficient mIDH astrocytomas (PMMRDIA) have a particularly poor prognosis. Here, we describe the biology of mIDH gliomas and review the literature regarding the emergence of mIDH inhibitors, including clinical trials in adults. Given the paucity of clinical trial data from pediatric patients with mIDH glioma, we propose guidelines for the inclusion of pediatric and AYA patients with gliomas onto prospective trials and expanded access programs as well as the potential of combined mIDH inhibition and immunotherapy in the treatment of patients with PMMRDIA at high risk of progression.

Outcomes in patients with acute myeloid leukemia older than 70 years within the last 30 years, a single center experience

As median age of patients with acute myeloid leukemia is 72 years, older patients continue to be a vulnerable cohort representing significant challenges in clinical practice. Patient-specific comorbidities as well as leukemia-specific unfavorable molecular- and cytogenetics confer even poorer outcomes. Treatment of AML therefore needs to be less toxic to prevent harm while lowering or eradicating leukemic burden to prolong survival. In this retrospective analysis we included 365 older AML patients from the Düsseldorf registry who were diagnosed and treated in our department of hematology over a period of 31 years. Most patients were treated with HMA (37.3%) followed by 35.3% of patients who received either low dose chemotherapy or BSC. 9% of patients were treated with induction chemotherapy while 8.5% of patients received a combination of HMA with venetoclax. 4.1% of patients underwent allografting. At the time of last follow up, 35 patients (9.6%) were still alive. Of those patients who were treated with induction chemotherapy or HMA + venetoclax, 18.2% and 29.0% were still alive, whereas 60% of the patients who underwent allogeneic stem cell transplantation were still alive (p < 0.001). Median overall survival of the entire patient population was 6 months. Longest survival was observed in patients who underwent aHSCT with an unreached median overall survival followed by patients who were treated with induction chemotherapy (21 months) or HMA plus venetoclax (11 months). The implementation of HMA + venetoclax and increasing numbers of aHSCT improved prognosis and survival even in older AML patients.

The prognostic significance of genetics in acute myeloid leukemia under venetoclax-based treatment

Acute myeloid leukemia (AML) is the most prevalent hematologic malignancy in adults. In 2022, the European LeukemiaNet (ELN) has updated its prognostic system that incorporates cytogenetics and molecular genetics based on data from patients undergoing intensive chemotherapy (IC). Recently, a risk stratification framework has been established for hypomethylating agents (HMA)-based low-intensity treatment (LIT) to fill the gaps in stratification for this treatment modality, but this needs further refinement. Venetoclax (VEN), a BH3 mimetic, targets BCL-2 to modulate apoptosis and metabolism in AML cells. Its combination with HMA or low-dose cytarabine (LDAC) has been shown to enhance the response rates and prolong the survival outcomes of older or unfit patients with AML. In this review, we delved into the prognostic significance of FLT3-ITD and IDH mutations when used in combination with VEN and HMA, as well as in conjunction with their specific inhibitors. We also explored the role of VEN in NPM1-mutated AML and its efficacy in splicing factor mutations AML. Additionally, we examined the response rates and survival outcomes of CBF-AML when treated with a VEN-based regimen. Moving forward, it is imperative that risk stratification for LIT becomes more nuanced to better align with the requirements of personalized diagnosis and treatment strategies.

Tumor energy metabolism: implications for therapeutic targets

Tumor energy metabolism plays a crucial role in the occurrence, progression, and drug resistance of tumors. The study of tumor energy metabolism has gradually become an emerging field of tumor treatment. Recent studies have shown that epigenetic regulation is closely linked to tumor energy metabolism, influencing the metabolic remodeling and biological traits of tumor cells. This review focuses on the primary pathways of tumor energy metabolism and explores therapeutic strategies to target these pathways. It covers key areas such as glycolysis, the Warburg effect, mitochondrial function, oxidative phosphorylation, and the metabolic adaptability of tumors. Additionally, this article examines the role of the epigenetic regulator SWI/SNF complex in tumor metabolism, specifically its interactions with glucose, lipids, and amino acids. Summarizing therapeutic strategies aimed at these metabolic pathways, including inhibitors of glycolysis, mitochondrial-targeted drugs, exploitation of metabolic vulnerabilities, and recent developments related to SWI/SNF complexes as potential targets. The clinical significance, challenges, and future directions of tumor metabolism research are discussed, including strategies to overcome drug resistance, the potential of combination therapy, and the application of new technologies.

Deciphering the multifaceted roles and clinical implications of 2-hydroxyglutarate in cancer

Increasing evidence indicates that 2-hydroxyglutarate (2HG) is an oncometabolite that drives tumour formation and progression. Due to mutations in isocitrate dehydrogenase (IDH) and the dysregulation of other enzymes, 2HG accumulates significantly in tumour cells. Due to its structural similarity to α-ketoglutarate (αKG), accumulated 2HG leads to the competitive inhibition of αKG-dependent dioxygenases (αKGDs), such as KDMs, TETs, and EGLNs. This inhibition results in epigenetic alterations in both tumour cells and the tumour microenvironment. This review comprehensively discusses the metabolic pathways of 2HG and the subsequent pathways influenced by elevated 2HG levels. We will delve into the molecular mechanisms by which 2HG exerts its oncogenic effects, particularly focusing on epigenetic modifications. This review will also explore the various methods available for the detection of 2HG, emphasising both current techniques and emerging technologies. Furthermore, 2HG shows promise as a biomarker for clinical diagnosis and treatment. By integrating these perspectives, this review aims to provide a comprehensive overview of the current understanding of 2HG in cancer biology, highlight the importance of ongoing research, and discuss future directions for translating these findings into clinical applications.

Recent advancements in biomarkers, therapeutics, and associated challenges in acute myeloid leukemia

Acute myeloid leukemia (AML) is a common type of leukemia that has a high mortality rate. The reasons for high mortality in patients with AML are therapeutic resistance, limited ability to predict duration of response, and likelihood of cancer relapse. Biomarkers, such as leukemic stem cell biomarkers, circulatory biomarkers, measurable residual disease biomarkers, and molecular biomarkers, are used for prognosis, diagnosis, and targeted killing to selectively eliminate AML cells. They also play an indispensable role in providing therapeutic resistance to patients with AML. Therefore, targeting these biomarkers will improve the outcome of AML patients. However, identifying biomarkers that can differentiate between treatment-responsive and non-responsive AML patients remains a challenge. This review discusses recent advancements in AML biomarkers, promising therapeutics, and associated challenges in the treatment of AML.

AML in the Elderly - When less may be more

PURPOSE OF REVIEW

We herein assess the distinct biological and clinical features of AML in older patients. We emphasize the importance of pre-treatment assessment to individualize care but note the changing treatment paradigm from intensive towards non-intensive therapy.

RECENT FINDING

Geriatric assessments and genetic data provide predictive information that guides treatment. During the past decade the FDA approved at least nine new targeted therapies, mostly small molecule inhibitors, in AML patients of all ages. These agents have created novel therapeutic options for this poorly chemo tolerant population whose AML tends to be intrinsically resistant to such therapy. Older AML patients may now be treated with less toxic therapy that provides similar, if not superior, efficacy compared with conventional chemotherapy. Although TP53 mutant AML remains a particular unmet need, additional novel agents on the horizon provide hope for improving outcomes for older adults with AML.

A review of the isocitrate dehydrogenase inhibitors in management of adult patients with AML and MDS

INTRODUCTION

The development of oral therapies impacts the management of acute myeloid leukemia and myelodysplastic syndromes, especially for targetable mutations including IDH1/2.

AREAS COVERED

We discuss IDH1/2 activity and inhibitor therapy in various settings, including monotherapy, combination therapy with hypomethylating agents, and other approaches.

EXPERT OPINION

Olutasidenib, enasidenib, and ivosidenib are approved for relapsed AML. Ivosidenib is approved for relapsed MDS and alone or with azacitidine in newly diagnosed AML. However, unanswered questions exist. In newly diagnosed AML, ivosidenib + azacitidine shows a survival benefit compared to azacitidine, but it is unknown whether ivosidenib + azacitidine demonstrates improved survival compared to ivosidenib. Ivosidenib + azacitidine demonstrated a survival benefit not seen with enasidenib + azacitidine. It is unclear whether newly diagnosed AML should be treated with azacitidine + ivosidenib or azacitidine + venetoclax. Azacitidine + venetoclax shows excellent response rates in IDH mutated disease. Retrospective data show low response rates of IDH inhibitor therapy post-venetoclax whereas HMA + venetoclax retains activity post IDH inhibition. The role of IDH inhibition post-transplant is unclear. Single-arm studies show post-transplant maintenance is safe; however, randomized trials are needed. Similarly, IDH inhibitors can be combined with chemotherapy however randomized studies are needed.

Safety considerations for drugs newly approved for treating acute myeloid leukemia

INTRODUCTION

Acute myeloid leukemia (AML) is typically characterized by a poor prognosis, mainly due to the median age at diagnosis. Until recently, treatment options were limited to intensive chemotherapy (IC) for young patients or hypomethylating agents for those ineligible for IC. Since 2017, nine molecules were registered for newly-diagnosed AML: midostaurin, gilteritinib, quizartinib, enasidenib, ivosidenib, gemtuzumab ozogamicin, CPX-351, glasdegib, and venetoclax.

AREAS COVERED

The review examines the safety profile of these drugs and their interactions with other agents used in supportive care. The PubMed and Google Scholar databases were searched for articles in English concerning new agents in AML from 2017 until 2023. Further relevant publications were obtained by reviewing the prescribing information and Food and Drug Administration (FDA) data.

EXPERT OPINION

The therapeutic spectrum in AML has broadened over several years and can also improve outcomes in older patients. However, in addition to their well-known cytotoxic activity, new molecules cause several unique, off-target toxicities. Also, potential drug-drug interactions (DDI) should be taken into consideration when choosing optimal first-line therapy; this remains a challenge in clinical practice.

Relapse and resistance in acute myeloid leukemia post venetoclax: improving second lines therapy and combinations

INTRODUCTION

The combined use of the BCL-2 inhibitor venetoclax with azacitidine now is the standard of care for patients with acute myeloid leukemia (AML) unfit for intensive chemotherapy with outcomes exceeding those achieved with hypomethylating agents alone. Venetoclax in combination with intensive chemotherapy is also increasingly used both as frontline as well as salvage therapy. However, resistance to and relapse after venetoclax-based therapies are of major concern and outcomes after treatment failure remain poor.

AREAS COVERED

A comprehensive search was performed using PubMed database (up to April 2024). Studies evaluating venetoclax-based combination treatments in AML and studies assessing markers of response and resistance to venetoclax were investigated. We summarize the status of venetoclax-based therapies in the frontline and relapsed/refractory setting with focus on the main mechanisms of resistance to BCL-2 inhibition. Further, strategies to overcome resistance including combinatorial regimens of hypomethylating agent (HMA) + venetoclax + inhibitors targeting actionable mutations like IDH1/2 or FLT3-ITD and the introduction of novel agents like menin-inhibitors are addressed.

EXPERT OPINION

Although venetoclax is reshaping the treatment of unfit and fit AML patients, prognosis of patients after HMA/VEN failure remains dismal, and strategies to abrogate primary and secondary resistance are an unmet clinical need.

IDH1 Inhibition Potentiates Chemotherapy Efficacy in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is associated with a 5-year overall survival rate of just 13%, and development of chemotherapy resistance is nearly universal. PDAC cells overexpress wild-type isocitrate dehydrogenase 1 (IDH1) that can enable them to overcome metabolic stress, suggesting it could represent a therapeutic target in PDAC. Here, we found that anti-IDH1 therapy enhanced the efficacy of conventional chemotherapeutics. Chemotherapy treatment induced reactive oxygen species (ROS) and increased tricarboxylic acid cycle activity in PDAC cells, along with the induction of wild-type IDH1 expression as a key resistance factor. IDH1 facilitated PDAC survival following chemotherapy treatment by supporting mitochondrial function and antioxidant defense to neutralize ROS through the generation of α-ketoglutarate and NADPH, respectively. Pharmacologic inhibition of wild-type IDH1 with ivosidenib synergized with conventional chemotherapeutics in vitro and potentiated the efficacy of subtherapeutic doses of these drugs in vivo in murine PDAC models. This promising treatment approach is translatable through available and safe oral inhibitors and provides the basis of an open and accruing clinical trial testing this combination (NCT05209074). Significance: Targeting IDH1 improves sensitivity to chemotherapy by suppressing mitochondrial function and inducing oxidative stress, supporting the potential of the combination as an effective strategy for treating pancreatic cancer.

Treatment of Acute Myeloid Leukemia in the Community Setting

The treatment landscape for acute myeloid leukemia (AML) is rapidly changing. Many new agents and lower-intensity regimens have been approved and can be safely used by hematologists and oncologists in both academic and community settings. The US Food and Drug Administration (FDA) held a virtual symposium on AML treatment in the community in November 2022. Several members of the FDA, along with practicing hematologists and oncologists in both academic and community settings, participated in the symposium. The goal of the symposium was to discuss challenges and opportunities in the treatment of patients with AML in community oncology settings. A summary of these discussions and key considerations are presented here.

Final phase 1 substudy results of ivosidenib for patients with mutant IDH1 relapsed/refractory myelodysplastic syndrome

ABSTRACT

Ivosidenib is a first-in-class mutant isocitrate dehydrogenase 1 (mIDH1) inhibitor with efficacy and tolerability in patients with advanced mIDH1 hematologic malignancies, leading to approval in frontline and relapsed/refractory (R/R) mIDH1 acute myeloid leukemia. We report final data from a phase 1 single-arm substudy of once-daily ivosidenib in patients with R/R mIDH1 myelodysplastic syndrome (MDS) after failure of standard-of-care therapies. Primary objectives were to determine safety, tolerability, and clinical activity. The primary efficacy end point was the complete remission (CR) + partial remission (PR) rate. Nineteen patients were enrolled; 18 were included in the efficacy analysis. Treatment-related adverse events occurred in 8 (42.1%) patients, including a grade 1 QT interval prolongation in 1 (5.3%) patient and grade 2 differentiation syndrome in 2 (10.5%) patients. Rates of CR + PR and objective response (CR + PR + marrow CR) were 38.9% (95% confidence interval [CI], 17.3-64.3) and 83.3% (95% CI, 58.6-96.4), respectively. Kaplan-Meier estimates showed a 68.6% probability of patients in CR achieving a remission duration of ≥5 years, and a median overall survival of 35.7 months. Of note, 71.4% and 75.0% baseline red blood cell (RBC)- and platelet-transfusion-dependent patients, respectively, became transfusion independent (TI; no transfusion for ≥56 days); 81.8% and 100% of baseline RBC and platelet TI patients, respectively, remained TI. One (5.3%) patient proceeded to a hematopoietic stem cell transplant. In conclusion, ivosidenib is clinically active, with durable remissions and a manageable safety profile observed in these patients. This trial was registered at www.ClinicalTrials.gov as #NCT02074839.

Molecular Features and Treatment Paradigms of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a common hematologic malignancy that is considered to be a disease of aging, and traditionally has been treated with induction chemotherapy, followed by consolidation chemotherapy and/or allogenic hematopoietic stem cell transplantation. More recently, with the use of next-generation sequencing and access to molecular information, targeted molecular approaches to the treatment of AML have been adopted. Molecular targeting is gaining prominence, as AML mostly afflicts the elderly population, who often cannot tolerate traditional chemotherapy. Understanding molecular changes at the gene level is also important for accurate disease classification, risk stratification, and prognosis, allowing for more personalized medicine. Some mutations are well studied and have an established gene-specific therapy, including FLT3 and IDH1/2, while others are being investigated in clinical trials. However, data on most known mutations in AML are still minimal and therapeutic studies are in pre-clinical stages, highlighting the importance of further research and elucidation of the pathophysiology involving these genes. In this review, we aim to highlight the key molecular alterations and chromosomal changes that characterize AML, with a focus on pathophysiology, presently available treatment approaches, and future therapeutic options.

Optimizing maintenance therapy in acute myeloid leukemia: where do we stand in the year 2024?

INTRODUCTION

Despite the prognosis of patients affected by acute myeloid leukemia (AML) improved in the last decade, most patients relapse. Maintenance therapy after a chemotherapy approach with or without allogeneic stem cell transplantation could be a way to control the undetectable residual burden of leukemic cells. Several studies are being carried out as maintenance therapy in AML. Some critical points need to be defined, how the physician can choose among the various drugs available.

AREAS COVERED

This review discusses the advances and controversies surrounding maintenance therapy for AML patients.

EXPERT OPINION

Patients withFLT3-positive AML should receive midostaurin or quizartinib in the first-linesetting. For a patient initially receiving midostaurin, consider switching to sorafenib in the post-transplant setting. Because of the improved safety profile and potency, many experts will lean toward using a second-generation FLT3 inhibitor such as quizartinib or gilteritinib. Finally, no data indicate whether maintenance therapy should be prolonged until progression or for a defined period.

Improved Outcome of Allogeneic Transplantation in Older Patients Treated for Myeloid Malignancies Using Post-Transplantation Cyclophosphamide and Reduced Duration of Immune Suppression

Allogeneic stem cell transplantation (alloSCT) offers curative potential for older patients with myeloid malignancies. We evaluated the efficacy and safety of alloSCT using post-transplantation cyclophosphamide (PTCy) in combination with a very short duration of immune suppression (IS) in this population. We retrospectively analyzed 92 consecutive patients aged 65 years and older who underwent an alloSCT for myeloid malignancies between February 2018 and December 2022 at our institution. Data on patient characteristics, treatment modalities, and outcomes were collected. Ninety-two patients received an alloSCT with PTCy-based graft versus host disease (GVHD) prophylaxis. The majority had minimal comorbidities and were diagnosed with acute myeloid leukemia. Patients mostly received conditioning regimens with low to intermediate transplant conditioning intensity scores. In 43% of patients, IS could be permanently stopped at day +90, resulting in a median time of IS of 2.93 months in high-risk patients. At a median follow-up of 21.3 months, the 1- and 2-year overall survival rates were 89% and 87%, respectively. Relapse-free survival rates were 88% and 84% at 1 and 2 years, respectively. The 1- and 2-year cumulative incidences of relapse were 8% and 13%, while treatment-related mortality (TRM) estimates were 9% at both time points. Acute GVHD grade 3 to 4 occurred in 7% within the first 180 days and severe chronic GVHD in 6% of patients. This all resulted in a 1- and 2-year graft versus host and relapse-free survival of 74% and 70%, respectively. AlloSCT using PTCy in combination with a short duration of IS in older patients with myeloid malignancies demonstrates favorable survival outcomes due to low relapse rates and a low TRM. The low incidence of relapse and acceptable rates of graft-versus-host disease suggest the efficacy and safety of this approach. Further studies are warranted to validate these findings and optimize transplant strategies for older patients with myeloid malignancies.

Clinical Implications of Isocitrate Dehydrogenase Mutations and Targeted Treatment of Acute Myeloid Leukemia with Mutant Isocitrate Dehydrogenase Inhibitors-Recent Advances, Challenges and Future Prospects

Despite the better understanding of the molecular mechanisms contributing to the pathogenesis of acute myeloid leukemia (AML) and improved patient survival in recent years, AML therapy still remains a clinical challenge. For this reason, it is important to search for new therapies that will enable the achievement of remission. Recently, the Food and Drug Administration approved three mutant IDH (mIDH) inhibitors for the treatment of AML. However, the use of mIDH inhibitors in monotherapy usually leads to the development of resistance and the subsequent recurrence of the cancer, despite the initial effectiveness of the therapy. A complete understanding of the mechanisms by which IDH mutations influence the development of leukemia, as well as the processes that enable resistance to mIDH inhibitors, may significantly improve the efficacy of this therapy through the use of an appropriate synergistic approach. The aim of this literature review is to present the role of IDH1/IDH2 mutations in the pathogenesis of AML and the results of clinical trials using mIDH1/IDH2 inhibitors in AML and to discuss the challenges related to the use of mIDH1/IDH2 inhibitors in practice and future prospects related to the potential methods of overcoming resistance to these agents.

Complete remission with partial hematological recovery as a palliative endpoint for treatment of acute myeloid leukemia

ABSTRACT

Complete remission with partial hematological recovery (CRh) has been used as an efficacy endpoint in clinical trials of nonmyelosuppressive drugs for acute myeloid leukemia (AML). We conducted a pooled analysis to characterize the clinical outcomes for patients with AML who achieved CRh after treatment with ivosidenib, olutasidenib, enasidenib, or gilteritinib monotherapy in clinical trials used to support marketing applications. The study cohort included 841 adult patients treated at the recommended drug dosage; 64.6% were red blood cell or platelet transfusion dependent at study baseline. Correlations between disease response and outcomes were assessed by logistic regression modeling for categorical variables and by Cox proportional hazards modeling for time-to-event variables. Patients with CRh had a higher proportion with transfusion independence (TI) for at least 56 days (TI-56; 92.3% vs 22.3%; P < .0001) or TI for at least 112 days (TI-112; 63.5% vs 8.7%; P < .0001), a reduced risk over time for severe infection (hazard ratio [HR], 0.43; P = .0007) or severe bleeding (HR, 0.17; P = .01), and a longer overall survival (OS; HR, 0.31; P < .0001) than patients with no response. The effects were consistent across drugs. In comparison with patients with CR, the effect sizes for CRh were similar for TI-56 and for risk over time of infection or bleeding but less for TI-112 and OS. CRh is associated with clinical benefits consistent with clinically meaningful palliative effects for the treatment of AML with nonmyelosuppressive drugs, although less robustly than for CR.

Molecular Targeting of the Isocitrate Dehydrogenase Pathway and the Implications for Cancer Therapy

The advent of comprehensive genomic profiling using next-generation sequencing (NGS) has unveiled an abundance of potentially actionable genetic aberrations that have shaped our understanding of the cancer biology landscape. Isocitrate dehydrogenase (IDH) is an enzyme present in the cytosol (IDH1) and mitochondria (IDH2 and IDH3). In the mitochondrion, it catalyzes the irreversible oxidative decarboxylation of isocitrate, yielding the production of α-ketoglutarate and nicotinamide adenine dinucleotide phosphate (NADPH) as well as carbon dioxide (CO2). In the cytosol, IDH catalyzes the decarboxylation of isocitrate to α-ketoglutarate as well as the reverse reductive carboxylation of α-ketoglutarate to isocitrate. These rate-limiting steps in the tricarboxylic acid cycle, as well as the cytoplasmic response to oxidative stress, play key roles in gene regulation, cell differentiation, and tissue homeostasis. Mutations in the genes encoding IDH1 and IDH2 and, less commonly, IDH3 have been found in a variety of cancers, most commonly glioma, acute myeloid leukemia (AML), chondrosarcoma, and intrahepatic cholangiocarcinoma. In this paper, we intend to elucidate the theorized pathophysiology behind IDH isomer mutation, its implication in cancer manifestation, and discuss some of the available clinical data regarding the use of novel IDH inhibitors and their role in therapy.

The CD33xCD123xCD70 Multispecific CD3-Engaging DARPin MP0533 Induces Selective T Cell-Mediated Killing of AML Leukemic Stem Cells

The prognosis of patients with acute myeloid leukemia (AML) is limited, especially for elderly or unfit patients not eligible for hematopoietic stem cell (HSC) transplantation. The disease is driven by leukemic stem cells (LSCs), which are characterized by clonal heterogeneity and resistance to conventional therapy. These cells are therefore believed to be a major cause of progression and relapse. We designed MP0533, a multispecific CD3-engaging designed ankyrin repeat protein (DARPin) that can simultaneously bind to three antigens on AML cells (CD33, CD123, and CD70), aiming to enable avidity-driven T cell-mediated killing of AML cells coexpressing at least two of the antigens. In vitro, MP0533 induced selective T cell-mediated killing of AML cell lines, as well as patient-derived AML blasts and LSCs, expressing two or more target antigens, while sparing healthy HSCs, blood, and endothelial cells. The higher selectivity also resulted in markedly lower levels of cytokine release in normal human blood compared to single antigen-targeting T-cell engagers. In xenograft AML mice models, MP0533 induced tumor-localized T-cell activation and cytokine release, leading to complete eradication of the tumors while having no systemic adverse effects. These studies show that the multispecific-targeting strategy used with MP0533 holds promise for improved selectivity toward LSCs and efficacy against clonal heterogeneity, potentially bringing a new therapeutic option to this group of patients with a high unmet need. MP0533 is currently being evaluated in a dose-escalation phase 1 study in patients with relapsed or refractory AML (NCT05673057).

Combination therapy with novel agents for acute myeloid leukaemia: Insights into treatment of a heterogenous disease

The treatment landscape of acute myeloid leukaemia (AML) is evolving rapidly. Venetoclax in combination with intensive chemotherapy or doublets or triplets with targeted or immune therapies is the focus of numerous ongoing trials. The development of mutation-targeted therapies has greatly enhanced the treatment armamentarium, with FLT3 inhibitors and isocitrate dehydrogenase inhibitors improving outcomes in frontline and relapsed/refractory (RR) AML, and menin inhibitors showing efficacy in RR NPM1mut and KMT2A-rearranged AML. With so many new drugs approved, the number of potential combinatorial approaches to leverage the maximal benefit of these agents has increased dramatically, while at the same time introducing clinical challenges, such as key preclinical and clinical data supporting the development of combinatorial therapy, how to optimally combine or sequence these novel agents, how to optimise dose and duration to maintain safety while enhancing efficacy, the optimal duration of therapy and the role of measurable residual disease in decision-making in both intensive and low-intensity therapy settings. In this review, we will outline the evidence leading to the approval of key agents in AML, their on-label current approvals and how they may be optimally combined in a safe and deliverable fashion to further improve outcomes in AML.

Transplant versus no transplant in myelodysplastic syndrome and acute myeloid leukemia with TP53 mutation; a referral center experience

A remarkably high rate of post-transplant relapse in patients with TP53-mutated myelodysplastic syndrome/acute myeloid leukemia (MDS/AML) calls to question the utility of allogeneic stem cell transplant (HSCT). We, therefore, performed a retrospective analysis to compare the outcomes between HSCT (N = 38) versus non-HSCT (N = 45) approaches. Patients in the HSCT cohort were younger (median age 63 vs. 72) while patients in the non-HSCT cohort more commonly had complex karyotype with chromosome 17 aberrancy and 5q deletion (p < .01). A total of 69 TP53 variants including 64 pathogenic variants, and 5 variants of undetermined significance were detected. Nine patients (4 in HSCT and 5 in non-HSCT) had multi-hit TP53 variants. After induction: 57.9% versus 56.6% in the HSCT versus non-HSCT cohort achieved morphologic complete remission. Median time to HSCT was 6 months and median follow-up was 15.1 months for HSCT and 5.7 months for non-HSCT. Median disease-free survival (DFS) and overall survival (OS) were 11.7 and 15.9 months for HSCT, and 4.1 and 5.7 months for non-HSCT cohorts, respectively. Non-relapse mortality at 12 months was 22% versus 44% for HSCT versus non-HSCT. In the HSCT cohort, the rate of grade II-IV acute and chronic graft-versus-host disease (GVHD) was 55% and 18%, respectively. None of the patients from the non-HSCT cohort were alive while four patients from the HSCT cohort were alive, in remission, and without GVHD (GRFS) at the time of abstraction. Better treatment strategies for patients with TP53-mutated MDS/AML remain an area of unmet clinical need.

Ivosidenib in Chinese patients with relapsed or refractory isocitrate dehydrogenase 1 mutated acute myeloid leukemia: a registry study

Ivosidenib, an isocitrate dehydrogenase 1 (IDH1) inhibitor, has demonstrated clinical benefits in a pivotal study (AG120-C-001) in patients with IDH1-mutated (mIDH1) acute myeloid leukemia (AML). A registry study (CS3010-101: NCT04176393) was conducted to assess the pharmacokinetic (PK) characteristics, safety, and efficacy of ivosidenib in Chinese patients with relapsed or refractory (R/R) mIDH1 AML. Patients received ivosidenib 500 mg once daily for 28-day cycles until disease progression. Ten subjects underwent intensive PK/progressive disease (PD) assessments. All subjects had the clinical response assessed at screening, every 28 days through month 12, and then every 56 days. Between November 12, 2019, and April 2, 2021, 30 patients were enrolled; 26 (86.7%) had de novo AML and 18 (60.0%) were transfusion-dependent at baseline. Following single and repeated doses of ivosidenib, median time to maximum plasma concentration (T max) was 4.0 and 2.0 hours, respectively. The inter-individual variability of pharmacokinetic exposure was moderate to high (coefficient of variation [CV], 25%-53%). No obvious accumulation was observed after repeated doses at cycle 2 day 1. Regarding the clinical response, the CR + CRh rate was 36.7% (95% confidence interval [CI]: 19.9%-56.1%), the median duration of CR + CRh was 19.7 months (95% CI: 2.9 months-not reached [NR]), and median duration of response (DoR) was 14.3 months (95% CI: 6.4 months-NR). Consistent clinical benefits and safety of ivosidenib were consistently observed at the final data cutoff with median follow-up time 26.0 months, as compared with primary data cutoff, and the data from Chinese R/R mIDH1 AML patients were also consistent with results from pivotal study.

Venetoclax therapy and emerging resistance mechanisms in acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a highly aggressive and devastating malignancy of the bone marrow and blood. For decades, intensive chemotherapy has been the frontline treatment for AML but has yielded only poor patient outcomes as exemplified by a 5-year survival rate of < 30%, even in younger adults. As knowledge of the molecular underpinnings of AML has advanced, so too has the development new strategies with potential to improve the treatment of AML patients. To date the most promising of these targeted agents is the BH3-mimetic venetoclax which in combination with standard of care therapies, has manageable non-haematological toxicity and exhibits impressive efficacy. However, approximately 30% of AML patients fail to respond to venetoclax-based regimens and almost all treatment responders eventually relapse. Here, we review the emerging mechanisms of intrinsic and acquired venetoclax resistance in AML and highlight recent efforts to identify novel strategies to overcome resistance to venetoclax.

Application of omics in the diagnosis, prognosis, and treatment of acute myeloid leukemia

Acute myeloid leukemia (AML) is the most frequent leukemia in adults with a high mortality rate. Current diagnostic criteria and selections of therapeutic strategies are generally based on gene mutations and cytogenetic abnormalities. Chemotherapy, targeted therapies, and hematopoietic stem cell transplantation (HSCT) are the major therapeutic strategies for AML. Two dilemmas in the clinical management of AML are related to its poor prognosis. One is the inaccurate risk stratification at diagnosis, leading to incorrect treatment selections. The other is the frequent resistance to chemotherapy and/or targeted therapies. Genomic features have been the focus of AML studies. However, the DNA-level aberrations do not always predict the expression levels of genes and proteins and the latter is more closely linked to disease phenotypes. With the development of high-throughput sequencing and mass spectrometry technologies, studying downstream effectors including RNA, proteins, and metabolites becomes possible. Transcriptomics can reveal gene expression and regulatory networks, proteomics can discover protein expression and signaling pathways intimately associated with the disease, and metabolomics can reflect precise changes in metabolites during disease progression. Moreover, omics profiling at the single-cell level enables studying cellular components and hierarchies of the AML microenvironment. The abundance of data from different omics layers enables the better risk stratification of AML by identifying prognosis-related biomarkers, and has the prospective application in identifying drug targets, therefore potentially discovering solutions to the two dilemmas. In this review, we summarize the existing AML studies using omics methods, both separately and combined, covering research fields of disease diagnosis, risk stratification, prognosis prediction, chemotherapy, as well as targeted therapy. Finally, we discuss the directions and challenges in the application of multi-omics in precision medicine of AML. Our review may inspire both omics researchers and clinical physicians to study AML from a different angle.

Ivosidenib significantly reduces triazole levels in patients with acute myeloid leukemia and myelodysplastic syndrome

BACKGROUND

Ivosidenib is primarily metabolized by CYP3A4; however, it induces CYP450 isozymes, including CYP3A4 and CYP2C9, whereas it inhibits drug transporters, including P-glycoprotein. Patients with acute myeloid leukemia are at risk of invasive fungal infections, and therefore posaconazole and voriconazole are commonly used in this population. Voriconazole is a substrate of CYP2C9, CYP2C19, and CYP3A4; therefore, concomitant ivosidenib may result in decreased serum concentrations. Although posaconazole is a substrate of P-glycoprotein, it is metabolized primarily via UDP glucuronidation; thus, the impact of ivosidenib on posaconazole exposure is unknown.

METHODS

Patients treated with ivosidenib and concomitant triazole with at least one serum trough level were included. Subtherapeutic levels were defined as posaconazole <700 ng/mL and voriconazole <1.0 µg/mL. The incidences of breakthrough invasive fungal infections and QTc prolongation were identified at least 5 days after initiation of ivosidenib with concomitant triazole.

RESULTS

Seventy-eight serum triazole levels from 31 patients receiving ivosidenib-containing therapy and concomitant triazole were evaluated. Of the 78 concomitant levels, 47 (60%) were subtherapeutic (posaconazole: n = 20 of 43 [47%]; voriconazole: n = 27 of 35 [77%]). Compared to levels drawn while patients were off ivosidenib, median triazole serum levels during concomitant ivosidenib were significantly reduced. There was no apparent increase in incidence of grade 3 QTc prolongation with concomitant azole antifungal and ivosidenib 500 mg daily.

CONCLUSIONS

This study demonstrated that concomitant ivosidenib significantly reduced posaconazole and voriconazole levels. Voriconazole should be avoided, empiric high-dose posaconazole (>300 mg/day) may be considered, and therapeutic drug monitoring is recommended in all patients receiving concomitant ivosidenib.

Isocitrate Dehydrogenase Mutations in Cancer: Mechanisms of Transformation and Metabolic Liability

Isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) are metabolic enzymes that interconvert isocitrate and 2-oxoglutarate (2OG). Gain-of-function mutations in IDH1 and IDH2 occur in a number of cancers, including acute myeloid leukemia, glioma, cholangiocarcinoma, and chondrosarcoma. These mutations cripple the wild-type activity of IDH and cause the enzymes to catalyze a partial reverse reaction in which 2OG is reduced but not carboxylated, resulting in production of the (R)-enantiomer of 2-hydroxyglutarate ((R)-2HG). (R)-2HG accumulation in IDH-mutant tumors results in profound dysregulation of cellular metabolism. The most well-characterized oncogenic effects of (R)-2HG involve the dysregulation of 2OG-dependent epigenetic tumor-suppressor enzymes. However, (R)-2HG has many other effects in IDH-mutant cells, some that promote transformation and others that induce metabolic dependencies. Herein, we review how cancer-associated IDH mutations impact epigenetic regulation and cellular metabolism and discuss how these effects can potentially be leveraged to therapeutically target IDH-mutant tumors.

AML treatment: conventional chemotherapy and emerging novel agents

Acute myeloid leukemia (AML) is driven by complex mutations and cytogenetic abnormalities with profound tumoral heterogeneity, making it challenging to treat. Ten years ago, the 5-year survival rate of patients with AML was only 29% with conventional chemotherapy and stem cell transplantation. All attempts to improve conventional therapy over the previous 40 years had failed. Now, new genomic, immunological, and molecular insights have led to a renaissance in AML therapy. Improvements to standard chemotherapy and a wave of new targeted therapies have been developed. However, how best to incorporate these advances into frontline therapy and sequence them in relapse is not firmly established. In this review, we highlight current treatments of AML, targeted agents, and pioneering attempts to synthesize these developments into a rational standard of care (SoC).

Management of isocitrate dehydrogenase 1/2 mutated acute myeloid leukemia

The emergence of next generation sequencing and widespread use of mutational profiling in acute myeloid leukemia (AML) has broadened our understanding of the heterogeneous molecular basis of the disease. Since genetic sequencing has become a standard practice, several driver mutations have been identified. Accordingly, novel targeted therapeutic agents have been developed and are now approved for the treatment of subsets of patients that carry mutations in FLT3, IDH1, and IDH2 [1, 2]. The emergence of these novel agents in AML offers patients a new modality of therapy, and shifts treatment paradigms toward individualized medicine. In this review, we outline the role of IDH mutations in malignant transformation, focus in on a novel group of targeted therapeutic agents directed toward IDH1- and IDH2-mutant AML, and explore their impact on prognosis in patients with AML.

Transplant Eligible and Ineligible Elderly Patients with AML-A Genomic Approach and Next Generation Questions

The management of elderly patients diagnosed with acute myelogenous leukemia (AML) is complicated by high relapse risk and comorbidities that often preclude access to allogeneic hematopoietic cellular transplantation (allo-HCT). In recent years, fast-paced FDA drug approval has reshaped the therapeutic landscape, with modest, albeit promising improvement in survival. Still, AML outcomes in elderly patients remain unacceptably unfavorable highlighting the need for better understanding of disease biology and tailored strategies. In this review, we discuss recent modifications suggested by European Leukemia Network 2022 (ELN-2022) risk stratification and review recent aging cell biology advances with the discussion of four AML cases. While an older age, >60 years, does not constitute an absolute contraindication for allo-HCT, the careful patient selection based on a detailed and multidisciplinary risk stratification cannot be overemphasized.

Advancements and Challenges in the Treatment of AML

The therapeutic arsenal for the management of AML has expanded significantly in recent years. Before 2017, newly diagnosed AML was treated with either standard cytarabine- and anthracycline-based induction chemotherapy (for all fit patients) or a single-agent hypomethylating agent (in unfit patients or those 75 years and older). While assessing patient fitness remains important, characterizing the disease biology has become critical to select the optimal initial therapy for each patient with more options available. FLT3 inhibitors, gemtuzumab ozogamicin, and CPX-351 have been shown to improve outcomes for specific subsets of patients. Venetoclax (VEN) with a hypomethylating agent (HMA) is the standard-of-care frontline regimen for most older patients, except perhaps for those with an IDH1 mutation where ivosidenib with azacitidine may also be considered. On the basis of the success seen with HMA/VEN in older patients, there is now increasing interest in incorporating VEN into frontline regimens in younger patients, with promising data from multiple early phase studies. This article focuses on recent updates and ongoing challenges in the management of AML, with a particular focus on the ongoing challenge of secondary AML and considerations regarding the selection of initial therapy in younger patients. An overview of common side effects and toxicities associated with targeted therapies is also presented here, along with recommended strategies to mitigate these risks.

Treating acute myelogenous leukemia in patients aged 70 and above: Recommendations from the International Society of Geriatric Oncology (SIOG)

Acute myeloid leukemia (AML) treatment is challenging in older patients. There is a lack of evidence-based recommendations for older patients ≥70, a group largely underrepresented in clinical trials. With new treatment options being available in recent years, recommendations are needed for these patients. As such the International Society of Geriatric Oncology (SIOG) assembled a task force to review the evidence specific to treatment and outcomes in this population of patients ≥70 years. Six questions were selected by the expert panel in domains of (1) baseline assessment, (2) frontline therapy, (3) post-remission therapy, (4) treatment for relapse, (5) targeted therapies, and (6) patient reported outcome/function and enhancing treatment tolerance. Information from current literature was extracted, combining evidence from systematic reviews/meta-analyses, decision models, individual trials targeting these patients, and subgroup data. Accordingly, recommendations were generated using a GRADE approach upon reviewing current evidence by consensus of the whole panel. It is our firm recommendation and hope that direct evidence should be generated for patients aged ≥70 as a distinct group in high need of improvement of their survival outcomes. Such studies should integrate information from a geriatric assessment to optimize external validity and outcomes.

Uptake of novel therapies into first-line treatment for acute myeloid leukemia patients: EU4 + UK perspective

Aim: To explore the incorporation of novel agents in the first-line setting for acute myeloid leukemia patients. Materials & methods: Observational study based on data from a multi-country cross-sectional retrospective web-based survey sent to 518 physicians in Europe between 2020 and 2021. Information from 2040 patients was analyzed. Results: 604 patients (29.6%) received novel agents in both intensive and non-intensive setting. Comorbidities were not a barrier for the use of novel agents. The presence of tumor mutations was observed to be an important element for treatment decision. Conclusion: There is a progressive incorporation of novel agents for newly diagnosed acute myeloid leukemia patients.