Ivosidenib or enasidenib combined with intensive chemotherapy in patients with newly diagnosed AML: a phase 1 study

High efficacy of azacitidine combined with homoharringtonine, idarubicin, and cytarabine in newly diagnosed patients with AML: A single arm, phase 2 trial

Introduction

This study aims to evaluate the efficacy and safety of the novel combination of Aza and HIA as the frontline induction therapy in newly diagnosed AML patients eligible for intensive chemotherapy (IC) (registered on ClinicalTrials.gov, number NCT04248595).

Methods

Aza (75mg/m2/d on days1-5 subcutaneous) is administered in combination with HIA [HHT 2mg/m2/d on days 4-8 intravenous over 3 hours, idarubicin 6mg/m2/d on days 4-6 intravenous, and cytarabine 100mg/m2/d on days 4-10 intravenous]. The primary endpoint was complete remission (CR) or CR with incomplete blood count recovery (CRi). Secondary endpoints were overall survival (OS), relapse-free survival (RFS), and adverse events (AEs).

Results

A total of 20 AML patients (aged 18-70 years) were enrolled between Jan 2020 and Sep 2022. 95% (19/20) of patients achieved CR/CRi, and 89.5% (17/19) had undetectable MRD, in which 94.7% (18/19) reached CR/CRi, and 88.9% (16/18) obtained MRD negative after the 1st cycle of induction therapy. Median OS and RFS were both not reached during the follow-up. The estimated 2-year OS and RFS were 87.5% (95%CI, 58.6% to 96.7%) and 87.1% (95%CI, 57.3% to 96.6%), respectively. No patient discontinued the treatment for AEs.

Discussion

This study provides preliminary evidence for this novel combination therapy as the first-line induction therapy for young or older AML patients fit for IC.

Role of Biomarkers in the Management of Acute Myeloid Leukemia

Despite many recent advances in treatment options, acute myeloid leukemia (AML) still has a high mortality rate. One important issue in optimizing outcomes for AML patients lies in the limited ability to predict response to specific therapies, duration of response, and likelihood of relapse. With evolving genetic characterization and improving molecular definitions, the ability to predict outcomes and long-term prognosis is slowly improving. The majority of the currently used prognostic assessments relate to molecular and chromosomal abnormalities, as well as response to initial therapy. These risk categories, however, do not account for a large amount of the variability in AML. Laboratory techniques now utilized in the clinic extend beyond bone marrow morphology and single gene sequencing, to next-generation sequencing of large gene panels and multiparameter flow cytometry, among others. Other technologic advances, such as gene expression analysis, have yet to demonstrate enough predictive and prognostic power to be employed in clinical medicine outside of clinical trials, but may be incorporated into the clinic in the future. In this review, we discuss the utility of current biomarkers, and present novel biomarker techniques and strategies that are in development for AML patients. Measurable residual disease (MRD) is a powerful prognostic tool that is increasingly being incorporated into clinical practice, and there are some exciting emerging biomarker technologies that have the potential to improve prognostic power in AML. As AML continues to be a difficult-to-treat disease with poor outcomes in many subtypes, advances in biomarkers that lead to better treatment decisions are greatly needed.

Molecular targets for the treatment of AML in the forthcoming 5th World Health Organization Classification of Haematolymphoid Tumours

INTRODUCTION

Acute myeloid leukemia (AML) is a genetically heterogeneous disease for which the treatment armamentarium has been historically restricted to chemotherapy. However, genomic and epigenomic alterations that contribute to AML initiation, maintenance, and relapse have disclosed new insights to the 5th update in WHO Classification of Haematolymphoid Tumours.

AREAS COVERED

After four decades of intensive chemotherapy as a 'one-size-fits-all' concept, several targeted agents have been approved for the treatment of AML. Several compounds, directed against regulators of apoptotic, epigenetic, or micro-environmental pathways, and immune-system modulators, are currently in development and investigation in clinical trials. We review advances in target-based therapy for AML focusing on their mechanism of action, examining the intracellular events and pathways, and the results from published clinical trials.

EXPERT OPINION

To improve patient clinical outcomes, find new biomarkers for therapeutic response, and pinpoint patients who might benefit from novel targeted medicines, next-generation sequencing is being used to evaluate AML-associated mutations. In fact, the new 5th edition of WHO classification has reaffirmed the importance of genetically defined entities that have a prognostic impact, but not all have a specific treatment available. New class of target drugs are in clinical development and could be beneficial to improve the therapeutic armamentarium available.

Updates on the Management of Acute Myeloid Leukemia

Acute myeloid leukemia is a heterogeneous disease defined by a large spectrum of genetic aberrations that are potential therapeutic targets. New targeted therapies have changed the landscape for a disease with poor outcomes. They are more effective than standard chemotherapy with a good safety profile. For "fit patients" in first-line, the combination of gemtuzumab ozogamicin or midostaurin with intensive chemotherapy or Vyxeos is now considered the "standard of care" for selected patients. On the other hand, for "unfit patients", azacitidine-venetoclax has been consolidated as a frontline treatment, while other combinations with magrolimab or ivosidenib are in development. Nevertheless, global survival results, especially in relapsed or refractory patients, remain unfavorable. New immunotherapies or targeted therapies, such as Menin inhibitors or sabatolimab, represent an opportunity in this situation. Future directions will probably come from combinations of different targeted therapies ("triplets") and maintenance strategies guided by measurable residual disease.

Targeting Glucose Metabolism Enzymes in Cancer Treatment: Current and Emerging Strategies

Simple Summary

Reprogramming of glucose metabolism is a hallmark of cancer and can be targeted by therapeutic agents. Some metabolism regulators, such as ivosidenib and enasidenib, have been approved for cancer treatment. Currently, more advanced and effective glucose metabolism enzyme-targeted anticancer drugs have been developed. Furthermore, some natural products have shown efficacy in killing tumor cells by regulating glucose metabolism, offering novel therapeutic opportunities in cancer. However, most of them have failed to be translated into clinical applications due to low selectivity, high toxicity, and side effects. Recent studies suggest that combining glucose metabolism modulators with chemotherapeutic drugs, immunotherapeutic drugs, and other conventional anticancer drugs may be a future direction for cancer treatment.

Abstract

Reprogramming of glucose metabolism provides sufficient energy and raw materials for the proliferation, metastasis, and immune escape of cancer cells, which is enabled by glucose metabolism-related enzymes that are abundantly expressed in a broad range of cancers. Therefore, targeting glucose metabolism enzymes has emerged as a promising strategy for anticancer drug development. Although several glucose metabolism modulators have been approved for cancer treatment in recent years, some limitations exist, such as a short half-life, poor solubility, and numerous adverse effects. With the rapid development of medicinal chemicals, more advanced and effective glucose metabolism enzyme-targeted anticancer drugs have been developed. Additionally, several studies have found that some natural products can suppress cancer progression by regulating glucose metabolism enzymes. In this review, we summarize the mechanisms underlying the reprogramming of glucose metabolism and present enzymes that could serve as therapeutic targets. In addition, we systematically review the existing drugs targeting glucose metabolism enzymes, including small-molecule modulators and natural products. Finally, the opportunities and challenges for glucose metabolism enzyme-targeted anticancer drugs are also discussed. In conclusion, combining glucose metabolism modulators with conventional anticancer drugs may be a promising cancer treatment strategy.

Contemporary evaluation of acute myeloid leukemia patients with long-term survival exceeding five years

OBJECTIVES

Define clinical and laboratory attributes of acute myeloid leukemia (AML) patients with long-term survival exceeding five years and compare them with AML patients succumbing to disease within two years of diagnosis.

METHODS

A retrospective analysis of AML patients alive at least five years from the time of initial diagnosis. Baseline clinical data were compared with patients who died within two years of diagnosis.

RESULTS

The long-term cohort consisted of 93 patients treated in 2007-2016 with a median follow-up duration of 7.7 years (range 5-13.6 years). European LeukemiaNet (ELN) 2017 favorable risk patients accounted for 60% of the cohort. All long-term survivors achieved remission following induction chemotherapy. Multivariate analysis showed that compared with 132 patients experiencing death within 2 years of diagnosis, long term survivors were more likely to be of younger age [odds ratio (OR), 0.92; 95% confidence interval (CI), 0.9-0.95; p<0.001], have a lower initial WBC count (OR, 0.58; 95% CI, 0.43-0.79; p=0.0004), undergo an allogeneic stem cell transplantation (OR, 7.95; 95% CI, 3.07-20.59; p<0.0001), and harbor favorable risk cytogenetics (OR, 0.03; 95% CI, 0.006-0.23; p=0.0004).

CONCLUSIONS

Long term survival of AML is seen in a distinct demographic and biologic patient subset.

Advances in the pharmacological management of acute myeloid leukemia in adults

INTRODUCTION

With advances in molecular medicine and precision approaches, there has been significant improvement in the treatment of acute myeloid leukemia (AML) in recent years. This reflects better understanding of molecular and metabolic pathways in leukemia cells, including BCL2 upregulation that prevents apoptosis, FLT3 tyrosine kinase activating mutations that allow uncontrolled proliferation, and IDH mutations that result in differentiation block.

AREAS COVERED

We performed a compressive review of important pre-clinical studies in AML that involve major molecular and metabolic pathways in AML, and we discussed standard therapeutic modalities and ongoing clinical trials for patients with AML, as well as an overall update of recent efforts in this area.

EXPERT OPINION

Targeting these pathways has resulted in improvement in the overall survival of some groups of AML patients. Secondary AML and TP53 mutated AML remain challenging subtypes of AML with limited treatment options and represent areas of unmet research need. Ongoing work with menin inhibitors in MLL rearranged leukemia, which comprise a large portion of secondary AML cases, the development of CAR T cell products and targeting the CD47 receptor on macrophages in myeloid neoplasms including in TP53 mutated AML have provided hope for these challenging subtypes of AML.

Recent advances of IDH1 mutant inhibitor in cancer therapy

Isocitrate dehydrogenase (IDH) is the key metabolic enzyme that catalyzes the conversion of isocitrate to α-ketoglutarate (α-KG). Two main types of IDH1 and IDH2 are present in humans. In recent years, mutations in IDH have been observed in several tumors, including glioma, acute myeloid leukemia, and chondrosarcoma. Among them, the frequency of IDH1 mutations is higher than IDH2. IDH1 mutations have been shown to increase the conversion of α-KG to 2-hydroxyglutarate (2-HG). IDH1 mutation-mediated accumulation of 2-HG leads to epigenetic dysregulation, altering gene expression, and impairing cell differentiation. A rapidly emerging therapeutic approach is through the development of small molecule inhibitors targeting mutant IDH1 (mIDH1), as evidenced by the recently approved of the first selective IDH1 mutant inhibitor AG-120 (ivosidenib) for the treatment of IDH1-mutated AML. This review will focus on mIDH1 as a therapeutic target and provide an update on IDH1 mutant inhibitors in development and clinical trials.

Isocitrate dehydrogenase 2 inhibitor enasidenib synergizes daunorubicin cytotoxicity by targeting aldo-keto reductase 1C3 and ATP-binding cassette transporters

Targeting mutations that trigger acute myeloid leukaemia (AML) has emerged as a refined therapeutic approach in recent years. Enasidenib (Idhifa) is the first selective inhibitor of mutated forms of isocitrate dehydrogenase 2 (IDH2) approved against relapsed/refractory AML. In addition to its use as monotherapy, a combination trial of enasidenib with standard intensive induction therapy (daunorubicin + cytarabine) is being evaluated. This study aimed to decipher enasidenib off-target molecular mechanisms involved in anthracycline resistance, such as reduction by carbonyl reducing enzymes (CREs) and drug efflux by ATP-binding cassette (ABC) transporters. We analysed the effect of enasidenib on daunorubicin (Daun) reduction by several recombinant CREs and different human cell lines expressing aldo-keto reductase 1C3 (AKR1C3) exogenously (HCT116) or endogenously (A549 and KG1a). Additionally, A431 cell models overexpressing ABCB1, ABCG2, or ABCC1 were employed to evaluate enasidenib modulation of Daun efflux. Furthermore, the potential synergism of enasidenib over Daun cytotoxicity was quantified amongst all the cell models. Enasidenib selectively inhibited AKR1C3-mediated inactivation of Daun in vitro and in cell lines expressing AKR1C3, as well as its extrusion by ABCB1, ABCG2, and ABCC1 transporters, thus synergizing Daun cytotoxicity to overcome resistance. This work provides in vitro evidence on enasidenib-mediated targeting of the anthracycline resistance actors AKR1C3 and ABC transporters under clinically achievable concentrations. Our findings may encourage its combination with intensive chemotherapy and even suggest that the effectiveness of enasidenib as monotherapy against AML could lie beyond the targeting of mIDH2.

New Drug Development and Clinical Trial Design by Applying Genomic Information Management

Depending on the patients’ genotype, the same drug may have different efficacies or side effects. With the cost of genomic analysis decreasing and reliability of analysis methods improving, vast amount of genomic information has been made available. Several studies in pharmacology have been based on genomic information to select the optimal drug, determine the dose, predict efficacy, and prevent side effects. This paper reviews the tissue specificity and genomic information of cancer. If the tissue specificity of cancer is low, cancer is induced in various organs based on a single gene mutation. Basket trials can be performed for carcinomas with low tissue specificity, confirming the efficacy of one drug for a single gene mutation in various carcinomas. Conversely, if the tissue specificity of cancer is high, cancer is induced in only one organ based on a single gene mutation. An umbrella trial can be performed for carcinomas with a high tissue specificity. Some drugs are effective for patients with a specific genotype. A companion diagnostic strategy that prescribes a specific drug for patients selected with a specific genotype is also reviewed. Genomic information is used in pharmacometrics to identify the relationship among pharmacokinetics, pharmacodynamics, and biomarkers of disease treatment effects. Utilizing genomic information, sophisticated clinical trials can be designed that will be better suited to the patients of specific genotypes. Genomic information also provides prospects for innovative drug development. Through proper genomic information management, factors relating to drug response and effects can be determined by selecting the appropriate data for analysis and by understanding the structure of the data. Selecting pre-processing and appropriate machine-learning libraries for use as machine-learning input features is also necessary. Professional curation of the output result is also required. Personalized medicine can be realized using a genome-based customized clinical trial design.

Novel Mechanisms for Post-Transplant Maintenance Therapy in Acute Myeloid Leukemia

Allogeneic stem cell transplantation has improved survival for patients with acute myeloid leukemia (AML), especially for patients with disease at high risk of relapse. However, relapse remains the most common cause of treatment failure and death in the post-transplant period. Maintenance therapy, an extended course of treatment after achieving remission to reduce the rate of relapse, is an important component of the treatment of various hematologic malignancies; however, its role in the treatment of AML is far less well-defined. Recently, there has been significant interest in the use of novel therapeutic agents as maintenance therapy after allogeneic stem cell transplant, utilizing new mechanisms of treatment and more favorable toxicity profiles. In this review, we will discuss the mechanistic and clinical data for post-transplant maintenance therapies in AML. Then, we will review several emergent and current clinical trials which aim to incorporate novel agents into maintenance therapy regimens.

The epigenetic dysfunction underlying malignant glioma pathogenesis

Comprehensive molecular profiling has dramatically transformed the diagnostic neuropathology of brain tumors. Diffuse gliomas, the most common and deadly brain tumor variants, are now classified by highly recurrent biomarkers instead of histomorphological characteristics. Several of the key molecular alterations driving glioma classification involve epigenetic dysregulation at a fundamental level, implicating fields of biology not previously thought to play major roles glioma pathogenesis. This article will review the major epigenetic alterations underlying malignant gliomas, their likely mechanisms of action, and potential strategies for their therapeutic targeting.

Prediction of survival with intensive chemotherapy in acute myeloid leukemia

Progress with intensive chemotherapy and supportive care measures has improved survival in newly diagnosed acute myeloid leukemia (AML). Predicting outcome helps in treatment decision making. We analyzed survival as the treatment endpoint in 3728 patients with newly diagnosed AML treated with intensive chemotherapy from 1980 to 2021. We divided the total study group (3:1 basis) into a training (n = 2790) and a validation group (n = 938). The associations between survival and 27 characteristics were investigated. In the training cohort, the multivariate analysis identified 12 consistent adverse prognostic variables independently associated with worse survival: older age, therapy-related myeloid neoplasm, worse performance status, cardiac comorbidity, leukocytosis, anemia, thrombocytopenia, elevated creatinine and lactate dehydrogenase, cytogenetic abnormalities, and the presence of infection at diagnosis except fever of unknown origin. We categorized patients into four prognostic groups, favorable (7%), intermediate (43%), poor (39%), and very poor (11%) with estimated 5-year survival rates of 69%, 36%, 13%, and 3% respectively (p < .001). The predictive model was validated in an independent cohort. In a subset of patients with molecular mutation profiles, adding the mutation profiles after accounting for the effects of previous factors identified NPM1 (favorable), PTPN11, and TP53 (both unfavorable) mutations as molecular prognostic factors. The new proposed predictive model for survival with intensive chemotherapy in patients with AML is robust and can be used to advise patients regarding their prognosis, to modify therapy in remission (e.g., proposing allogeneic stem cell transplantation in first remission), and to compare outcome and benefits on future investigational therapies.

Prevalence and Prognostic Role of IDH Mutations in Acute Myeloid Leukemia: Results of the GIMEMA AML1516 Protocol

IDH1/2 mutations are common in acute myeloid leukemia (AML) and represent a therapeutic target. The GIMEMA AML1516 observational protocol was designed to study the prevalence of IDH1/2 mutations and associations with clinico-biological parameters in a cohort of Italian AML patients. We analyzed a cohort of 284 AML consecutive patients at diagnosis, 139 females and 145 males, of a median age of 65 years (range: 19−86). Of these, 38 (14%) harbored IDH1 and 51 (18%) IDH2 mutations. IDH1/2 mutations were significantly associated with WHO PS >2 (p < 0.001) and non-complex karyotype (p = 0.021) when compared to IDH1/2-WT. Furthermore, patients with IDH1 mutations were more frequently NPM1-mutated (p = 0.007) and had a higher platelet count (p = 0.036). At relapse, IDH1/2 mutations were detected in 6 (25%) patients. As per the outcome, 60.5% of IDH1/2-mutated patients achieved complete remission; overall survival and event-free survival at 2 years were 44.5% and 36.1%, respectively: these rates were similar to IDH1/2-WT. In IDH1/2-mutated patients, high WBC proved to be an independent prognostic factor for survival. In conclusion, the GIMEMA AML1516 confirms that IDH1/2 mutations are frequently detected at diagnosis and underlines the importance of recognizing IDH1/2-mutated cases up-front to offer the most appropriate therapeutic strategy, given the availability of IDH1/2 inhibitors.

Resistance to targeted therapies: delving into FLT3 and IDH

Recent advances in FLT3 and IDH targeted inhibition have improved response rates and overall survival in patients with mutations affecting these respective proteins. Despite this success, resistance mechanisms have arisen including mutations that disrupt inhibitor-target interaction, mutations impacting alternate pathways, and changes in the microenvironment. Here we review the role of these proteins in leukemogenesis, their respective inhibitors, mechanisms of resistance, and briefly ongoing studies aimed at overcoming resistance.

2-Hydroxyglutarate in Acute Myeloid Leukemia: A Journey from Pathogenesis to Therapies

The oncometabolite 2-hydroxyglutarate (2-HG) plays a key role in differentiation blockade and metabolic reprogramming of cancer cells. Approximatively 20–30% of acute myeloid leukemia (AML) cases carry mutations in the isocitrate dehydrogenase (IDH) enzymes, leading to a reduction in the Krebs cycle intermediate α-ketoglutarate (α-KG) to 2-HG. Relapse and chemoresistance of AML blasts following initial good response to standard therapy account for the very poor outcome of this pathology, which represents a great challenge for hematologists. The decrease of 2-HG levels through pharmacological inhibition of mutated IDH enzymes induces the differentiation of AML blasts and sensitizes leukemic cells to several anticancer drugs. In this review, we provide an overview of the main genetic mutations in AML, with a focus on IDH mutants and the role of 2-HG in AML pathogenesis. Moreover, we discuss the impact of high levels of 2-HG on the response of AML cells to antileukemic therapies and recent evidence for highly efficient combinations of mutant IDH inhibitors with other drugs for the management of relapsed/refractory (R/R) AML.

Digital Droplet PCR in Hematologic Malignancies: A New Useful Molecular Tool

Digital droplet PCR (ddPCR) is a recent version of quantitative PCR (QT-PCR), useful for measuring gene expression, doing clonality assays and detecting hot spot mutations. In respect of QT-PCR, ddPCR is more sensitive, does not need any reference curve and can quantify one quarter of samples already defined as "positive but not quantifiable". In the IgH and TCR clonality assessment, ddPCR recapitulates the allele-specific oligonucleotide PCR (ASO-PCR), being not adapt for detecting clonal evolution, that, on the contrary, does not represent a pitfall for the next generation sequencing (NGS) technique. Differently from NGS, ddPCR is not able to sequence the whole gene, but it is useful, cheaper, and less time-consuming when hot spot mutations are the targets, such as occurs with IDH1, IDH2, NPM1 in acute leukemias or T315I mutation in Philadelphia-positive leukemias or JAK2 in chronic myeloproliferative neoplasms. Further versions of ddPCR, that combine different primers/probes fluorescences and concentrations, allow measuring up to four targets in the same PCR reaction, sparing material, time, and money. ddPCR is also useful for quantitating BCR-ABL1 fusion gene, WT1 expression, donor chimerism, and minimal residual disease, so helping physicians to realize that "patient-tailored therapy" that is the aim of the modern hematology.

Impact of IDH1 and IDH2 mutation detection at diagnosis and in remission in patients with AML receiving allogeneic transplantation

Somatic mutations in the isocitrate dehydrogenase 1 and 2 genes (IDH1 and IDH2) are common in acute myeloid leukemia (AML). The prognostic impact of the presence of IDH mutations may be influenced by the comutational status, the specific location of the mutation (ie, IDH1 R132, IDH2 R140, and IDH2 R172) at diagnosis, and the dynamics of the mutation burden during disease course. Even though many patients with IDH-mutated AML are consolidated by hematopoietic stem cell transplantation (HSCT), the underlying biology and prognostic consequences remain largely unknown. Here, we present a large analysis of 292 patients with AML who received HSCT in complete remission (CR) or CR with incomplete peripheral recovery (CRi), in which we assessed the IDH mutation status at diagnosis and HSCT as a potential marker for measurable residual disease (MRD). About a quarter of all patients were IDH-mutated at diagnosis. The diagnostic presence of IDH mutations in AML did not have a significant prognostic impact when consolidated with HSCT. However, IDH1 R132 and IDH2 R172 MRD positivity in remission at HSCT associated with an increased risk of relapse, while IDH2 R140 mutations did not. The IDH2 R140 variant allele frequency (VAF) at diagnosis was higher, clustering around 50%, and the mutation clearance at HSCT in morphologic remission was much lower compared with IDH1 R132 and IDH2 R172. In our cohort, IDH2 R140 mutations behaved more like a clonal hematopoiesis-related aberration, while IDH1 R132 and IDH2 R172 harbored AML disease-specific features.

Infectious complications of targeted drugs and biotherapies in acute leukemia. Clinical practice guidelines by the European Conference on Infections in Leukemia (ECIL), a joint venture of the European Group for Blood and Marrow Transplantation (EBMT), the European Organization for Research and Treatment of Cancer (EORTC), the International Immunocompromised Host Society (ICHS) and the European Leukemia Net (ELN)

The 9th web-based European Conference on Infections in Leukemia (ECIL-9), held September 16-17, 2021, reviewed the risk of infections and febrile neutropenia associated with more recently approved immunotherapeutic agents and molecular targeted drugs for the treatment of acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). Novel antibody based treatment approaches (inotuzumab ozogamicin, gemtuzumab ozogamicin, flotetuzumab), isocitrate dehydrogenases inhibitors (ivosidenib, enasidenib, olutasidenib), FLT3 kinase inhibitors (gilteritinib, midostaurin, quizartinib), a hedgehog inhibitor (glasdegib) as well as a BCL2 inhibitor (venetoclax) were reviewed with respect to their mode of action, their immunosuppressive potential, their current approval and the infectious complications and febrile neutropenia reported from clinical studies. Evidence-based recommendations for prevention and management of infectious complications and specific alerts regarding the potential for drug-drug interactions were developed and discussed in a plenary session with the panel of experts until consensus was reached. The set of recommendations was posted on the ECIL website for a month for comments from members of EBMT, EORTC, ICHS and ELN before final approval by the panelists. While a majority of these agents are not associated with a significantly increased risk when used as monotherapy, caution is required with combination therapy such as venetoclax plus hypomethylating agents, gemtuzumab ozogamicin plus cytotoxic drugs or midostaurin added to conventional AML chemotherapy.

Nonmyeloablative Allogeneic Transplantation With Post-Transplant Cyclophosphamide for Acute Myeloid Leukemia With IDH Mutations: A Single Center Experience

INTRODUCTION

Mutations in the IDH1 or IDH2 genes are detected in approximately 20% of cases of acute myeloid leukemia (AML). Few studies have examined the impact of IDH mutations in AML on allogeneic bone marrow transplant (alloBMT) outcomes.

PATIENTS AND METHODS

In this single center study, alloBMT outcomes for 61 patients with IDH-mutated (mIDH) AML were compared to those for 146 patients with IDH-wildtype (wtIDH) AML.

RESULTS

Patients with mIDH AML had a 2-year overall survival (OS) of 85% (95% CI 76%-95%), 2-year relapse free survival (RFS) of 71% (95% CI 59%-85%), 1-year cumulative incidence of relapse (CIR) of 14% (95% CI 5%-23%) and a 1-year cumulative incidence of transplant related mortality (CITRM) of 3% (95% CI 0%-8%). Patients with wtIDH had a 2-year OS of 61% (95% CI 53%-70%), 2-year RFS of 58% (95% CI 50%-67%), 1-year CIR of 27% (95% CI 20%-35%), and a 1-year CITRM of 9% (95% CI 5%-14%). In a univariate analysis cox-proportional hazard model, mIDH was associated with significantly better OS (HR 0.52, 95% CI 0.29-0.96) and a trend toward better RFS (HR 0.60, 95% CI 0.35-1.01). After controlling for donor age, diagnosis, and ELN risk category, mIDH was associated with a nonsignificantly improved OS (HR 0.54, 95% CI 0.29-1.01) and RFS (HR 0.67, 95% CI 0.39-1.15).

CONCLUSION

Among patients with mIDH AML, patients who received a peritransplant IDH inhibitor had improved OS (P = .03) compared to those who did not, but there was no detectable difference for RFS (P = .29).

New Perspectives in Treating Acute Myeloid Leukemia: Driving towards a Patient-Tailored Strategy

For decades, intensive chemotherapy (IC) has been considered the best therapeutic option for treating acute myeloid leukemia (AML), with no curative option available for patients who are not eligible for IC or who have had failed IC. Over the last few years, several new drugs have enriched the therapeutic arsenal of AML treatment for both fit and unfit patients, raising new opportunities but also new challenges. These include the already approved venetoclax, the IDH1/2 inhibitors enasidenib and ivosidenib, gemtuzumab ozogamicin, the liposomal daunorubicin/cytarabine formulation CPX-351, and oral azacitidine. Venetoclax, an anti BCL2-inhibitor, in combination with hypomethylating agents (HMAs), has markedly improved the management of unfit and elderly patients from the perspective of improved quality of life and better survival. Venetoclax is currently under investigation in combination with other old and new drugs in early phase trials. Recently developed drugs with different mechanisms of action and new technologies that have already been investigated in other settings (BiTE and CAR-T cells) are currently being explored in AML, and ongoing trials should determine promising agents, more synergic combinations, and better treatment strategies. Access to new drugs and inclusion in clinical trials should be strongly encouraged to provide scientific evidence and to define the future standard of treatment in AML.

Increasing Role of Targeted Immunotherapies in the Treatment of AML

Acute myeloid leukemia (AML) is the most common acute leukemia in adults. The standard of care in medically and physically fit patients is intensive induction therapy. The majority of these intensively treated patients achieve a complete remission. However, a high number of these patients will experience relapse. In patients older than 60 years, the results are even worse. Therefore, new therapeutic approaches are desperately needed. One promising approach in high-risk leukemia to prevent relapse is the induction of the immune system simultaneously or after reduction of the initial tumor burden. Different immunotherapeutic approaches such as allogenic stem cell transplantation or donor lymphocyte infusions are already standard therapies, but other options for AML treatment are in the pipeline. Moreover, the therapeutic landscape in AML is rapidly changing, and in the last years, a number of immunogenic targets structures eligible for specific therapy, risk assessment or evaluation of disease course were determined. For example, leukemia-associated antigens (LAA) showed to be critical as biomarkers of disease state and survival, as well as markers of minimal residual disease (MRD). Yet many mechanisms and properties are still insufficiently understood, which also represents a great potential for this form of therapy. Therefore, targeted therapy as immunotherapy could turn into an efficient tool to clear residual disease, improve the outcome of AML patients and reduce the relapse risk. In this review, established but also emerging immunotherapeutic approaches for AML patients will be discussed.

Translating recent advances in the pathogenesis of acute myeloid leukemia to the clinic

Despite FDA approval of nine new drugs for patients with acute myeloid leukemia (AML) in the United States over the last 4 years, AML remains a major area of unmet medical need among hematologic malignancies. In this review, we discuss the development of promising new molecular targeted approaches for AML, including menin inhibition, novel IDH1/2 inhibitors, and preclinical means to target TET2, ASXL1, and RNA splicing factor mutations. In addition, we review progress in immune targeting of AML through anti-CD47, anti-SIRPα, and anti-TIM-3 antibodies; bispecific and trispecific antibodies; and new cellular therapies in development for AML.

Emerging Targeted Therapy for Specific Genomic Abnormalities in Acute Myeloid Leukemia

We describe recent updates of existing molecular-targeting agents and emerging novel gene-specific strategies. FLT3 and IDH inhibitors are being tested in combination with conventional chemotherapy for both medically fit patients and patients who are ineligible for intensive therapy. FLT3 inhibitors combined with non-cytotoxic agents, such as BCL-2 inhibitors, have potential therapeutic applicability. The menin-MLL complex pathway is an emerging therapeutic target. The pathway accounts for the leukemogenesis in AML with MLL-rearrangement, NPM1 mutation, and NUP98 fusion genes. Potent menin-MLL inhibitors have demonstrated promising anti-leukemic effects in preclinical studies. The downstream signaling molecule SYK represents an additional target. However, the TP53 mutation continues to remain a challenge. While the p53 stabilizer APR-246 in combination with azacitidine failed to show superiority compared to azacitidine monotherapy in a phase 3 trial, next-generation p53 stabilizers are now under development. Among a number of non-canonical approaches to TP53-mutated AML, the anti-CD47 antibody magrolimab in combination with azacitidine showed promising results in a phase 1b trial. Further, the efficacy was somewhat better in patients with the TP53 mutation. Although clinical evidence has not been accumulated sufficiently, targeting activating KIT mutations and RAS pathway-related molecules can be a future therapeutic strategy.

Pharmacokinetic/Pharmacodynamic Evaluation of Ivosidenib or Enasidenib Combined With Intensive Induction and Consolidation Chemotherapy in Patients With Newly Diagnosed IDH1/2-Mutant Acute Myeloid Leukemia

Mutant isocitrate dehydrogenase 1/2 (mIDH1/2) proteins catalyze production of the oncometabolite D-2-hydroxyglutarate (2-HG). Ivosidenib and enasidenib are oral inhibitors of mIDH1 and mIDH2, respectively. An open-label phase 1 study is evaluating the safety and efficacy of ivosidenib or enasidenib combined with intensive induction and consolidation chemotherapy in adult patients with newly diagnosed mIDH1/2 acute myeloid leukemia (AML; NCT02632708). In this population, we characterized the pharmacokinetics (PK), pharmacodynamics (PD), and PK/PD relationships for ivosidenib and enasidenib. Patients received continuous oral ivosidenib 500 mg once daily or enasidenib 100 mg once daily combined with chemotherapy. Serial blood samples were collected for measurement of the concentrations of the mIDH inhibitors. 2-HG concentrations were measured in both plasma and bone marrow aspirates. Samples were collected from 60 patients receiving ivosidenib and 91 receiving enasidenib. For both drugs, exposures at steady state were higher than after single doses, with mean accumulation ratios (based on area under the plasma concentration-time curve from time 0 to 24 hours) of 2.35 and 8.25 for ivosidenib and enasidenib, respectively. Mean plasma 2-HG concentrations were elevated at baseline. After multiple ivosidenib or enasidenib doses, mean trough plasma 2-HG concentrations decreased to levels observed in healthy individuals and were maintained with continued dosing. There was a corresponding reduction in bone marrow 2-HG concentrations. When combined with intensive chemotherapy in patients with newly diagnosed mIDH1/2 AML, ivosidenib and enasidenib demonstrated PK/PD profiles similar to those when they are given as single agents. These findings support the dosing of ivosidenib or enasidenib in combination with intensive chemotherapy for the treatment of patients with newly diagnosed mIDH1/2 AML.

Put in a “Ca2+ll” to Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a clonal disorder characterized by genetic aberrations in myeloid primitive cells (blasts) which lead to their defective maturation/function and their proliferation in the bone marrow (BM) and blood of affected individuals. Current intensive chemotherapy protocols result in complete remission in 50% to 80% of AML patients depending on their age and the AML type involved. While alterations in calcium signaling have been extensively studied in solid tumors, little is known about the role of calcium in most hematologic malignancies, including AML. Our purpose with this review is to raise awareness about this issue and to present (i) the role of calcium signaling in AML cell proliferation and differentiation and in the quiescence of hematopoietic stem cells; (ii) the interplay between mitochondria, metabolism, and oxidative stress; (iii) the effect of the BM microenvironment on AML cell fate; and finally (iv) the mechanism by which chemotherapeutic treatments modify calcium homeostasis in AML cells.

CARving the Path to Allogeneic CAR T Cell Therapy in Acute Myeloid Leukemia

Despite advances in the understanding of the genetic landscape of acute myeloid leukemia (AML) and the addition of targeted biological and epigenetic therapies to the available armamentarium, achieving long-term disease-free survival remains an unmet need. Building on growing knowledge of the interactions between leukemic cells and their bone marrow microenvironment, strategies to battle AML by immunotherapy are under investigation. In the current review we describe the advances in immunotherapy for AML, with a focus on chimeric antigen receptor (CAR) T cell therapy. CARs constitute powerful immunologic modalities, with proven clinical success in B-Cell malignancies. We discuss the challenges and possible solutions for CAR T cell therapy development in AML, and examine the path currently being paved by preclinical and clinical efforts, from autologous to allogeneic products.

The cure of leukemia through the optimist's prism

Progress is occurring at a dizzying rate across all leukemias. Since the authors' review of the topic in Cancer in 2018, numerous discoveries have been made that have improved the therapy and outcomes of several leukemia subsets. Hairy cell leukemia is potentially curable with a single course of cladribine followed by rituximab (10-year survival, ≥90%). Acute promyelocytic leukemia is curable at a rate of 80% to 90% with a nonchemotherapy regimen of all-trans retinoic acid and arsenic trioxide. The cure rate for core-binding factor acute myeloid leukemia (AML) is ≥75% with fludarabine, high-dose cytarabine, and gemtuzumab ozogamicin. Survival for patients with chronic myeloid leukemia is close to that for an age-matched normal population with BCR-ABL1 tyrosine kinase inhibitors (TKIs). Chronic lymphocytic leukemia, a previously incurable disease, may now be potentially curable with a finite duration of therapy with Bruton tyrosine kinase inhibitors and venetoclax. The estimated 5-year survival rate for patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) exceeds 70% with intensive chemotherapy and ponatinib, a third-generation BCR-ABL1 TKI, and more recent nonchemotherapy regimens using dasatinib or ponatinib with blinatumomab are producing outstanding results. Survival in both younger and older patients with ALL has improved with the addition of antibodies targeting CD20, CD19 (blinatumomab), and CD22 (inotuzumab) to chemotherapy. Several recent drug discoveries (venetoclax, FLT3 and IDH inhibitors, and oral hypomethylating agents) are also improving outcomes for younger and older patients with AML and for those with higher risk myelodysplastic syndrome.

Guanosine primes acute myeloid leukemia for differentiation via guanine nucleotide salvage synthesis

Differentiation arrest represents a distinct hallmark of acute myeloid leukemia (AML). Identification of differentiation-induction agents that are effective across various subtypes remains an unmet challenge. GTP biosynthesis is elevated in several types of cancers, considered to support uncontrolled tumor growth. Here we report that GTP overload by supplementation of guanosine, the nucleoside precursor of GTP, poises AML cells for differentiation and growth inhibition. Transcriptome profiling of guanosine-treated AML cells reveals a myeloid differentiation pattern. Importantly, the treatment compromises leukemia progression in AML xenograft models. Mechanistically, GTP overproduction requires sequential metabolic conversions executed by the purine salvage biosynthesis pathway including the involvement of purine nucleoside phosphorylase (PNP) and hypoxanthine phosphoribosyltransferase 1 (HPRT1). Taken together, our study offers novel metabolic insights tethering GTP homeostasis to myeloid differentiation and provides an experimental basis for further clinical investigations of guanosine or guanine nucleotides in the treatment of AML patients.

Prediction of early (4-week) mortality in acute myeloid leukemia with intensive chemotherapy

The progress with intensive chemotherapy and supportive care measures has improved survival in patients with newly diagnosed acute myeloid leukemia (AML). Given the recent development of effective low intensity therapies, an optimal decision on the therapy intensity may improve survival through the avoidance of early mortality. We reviewed the outcome of 3728 patients with newly diagnosed AML who received intensive chemotherapy between August 1980 and May 2020. Intensive chemotherapy was defined as a cumulative cytarabine dose ≥ 700 mg/m² during induction therapy. We divided the whole cohort into a training and validation group at a 3:1 ratio. The population was divided into a training (2790 patients) and a validation cohort (938 patients). The median age was 55 years (range, 15-99). Among them, 442 patients (12%) had core-binding factor AML. Binary logistic regression identified older age, worse performance status, hyperbilirubinemia, elevated creatinine, hyperuricemia, cytogenetic abnormalities other than CBF and -Y, and pneumonia as adverse prognostic factors for an early 4-week mortality. This risk classification for early mortality was verified in the validation cohort of patients. In the validation cohort of more recently treated patients from 2000 to 2017, the 4-week mortality rates with intensive chemotherapy were 2%, 14%, and 50% in the low-, high-, and very high-risk group, respectively. The mortality rates with low intensity therapies were 3%, 9%, and 20%, respectively. The risk classification guides treatment intensity by the assessment of age, frailty, organ dysfunction, cytogenetic abnormality, and infection to avoid early mortality.

Older Patients with Acute Myeloid Leukemia Deserve Individualized Treatment

PURPOSE OF REVIEW

Treatment of elderly patients with acute myeloid leukemia is a known challenge for hematologists due to patient diversity, heterogeneous disease biology, and a rapidly evolving treatment landscape. Here, we highlight the importance of determining fitness, review the latest therapeutic developments, and discuss clinical scenarios to provide guidance on individualized treatment for older AML patients.

RECENT FINDINGS

Several factors, like age, performance status, and comorbidities, play a role in fitness and are associated with outcome. Comorbidity scoring systems and geriatric assessments are tools to help physicians select the most appropriate treatment for each patient. The addition of venetoclax, targeted therapy with IDH1/2 and FLT3 inhibitors, and enhanced formulas of existing drugs like CPX-351 and oral azacitidine have improved responses and outcomes. New drugs and combination therapies have increased the therapeutic options for elderly AML patients but determination of fitness and disease biology is essential to select patient-tailored treatments.

IDH1/2 Mutations in Cancer Stem Cells and Their Implications for Differentiation Therapy

Isocitrate dehydrogenase 1 and 2 (IDH1/2) are enzymes recurrently mutated in various types of cancer, including glioma, cholangiocarcinoma, chondrosarcoma, and acute myeloid leukemia. Mutant IDH1/2 induce a block in differentiation and thereby contribute to the stemness and oncogenesis of their cells of origin. Recently, small-molecule inhibitors of mutant IDH1/2 have been Food and Drug Administration-approved for the treatment of IDH1/2-mutated acute myeloid leukemia. These inhibitors decrease the stemness of the targeted IDH1/2-mutated cancer cells and induce their differentiation to more mature cells. In this review, we elucidate the mechanisms by which mutant IDH1/2 induce a block in differentiation and the biological and clinical effects of the release into differentiation by mutant-IDH1/2 inhibitors. (J Histochem Cytochem 70:83-97, 2022).

Clinical development of IDH1 inhibitors for cancer therapy

Isocitrate dehydrogenase 1 (IDH1) has been investigated as a promising therapeutic target in select cancers with a mutated version of the enzyme (mtIDH1). With only one phase III trial published to date and two indications approved for routine clinical use by the FDA, we reviewed the entire clinical trial portfolio to broadly understand mtIDH1 inhibitor activity in patients. We queried PubMed.gov and ClinicalTrials.gov to identify published and ongoing clinical trials related to IDH1 and cancer. Progression-free survival (PFS), overall survival (OS), 2-hydroxyglutarate levels, and adverse events were summarized. To date, ten clinical trials investigating mtIDH1 inhibitors among patients with diverse malignancies (cholangiocarcinoma, acute myeloid leukemia, chondrosarcoma, glioma) have been published. Almost every trial (80%) has investigated ivosidenib. In multiple phase I trials, ivosidenib treatment resulted in promising radiographic and biochemical responses with improved survival outcomes (relative to historic data) among patients with both solid and hematologic mtIDH1 malignancies. Among patients enrolled in a phase III trial with advanced cholangiocarcinoma, ivosidenib resulted in a PFS rate of 32% at 6 months, as compared to 0% with placebo. There was a 5.2 month increase in OS with ivosidenib relative to placebo, after considering crossover. The treatment-specific grade ≥3 adverse event rate of ivosidenib was 2%-26% among all patients, and was just 3.6% among 284 patients who had a solid tumor across four trials. Although <1% of malignancies harbor IDH1 mutations, small molecule mtIDH1 inhibitors, namely ivosidenib, appear to be biologically active and well tolerated in patients with solid and hematologic mtIDH1 malignancies.

The future of research in hematology: Integration of conventional studies with real-world data and artificial intelligence

Most national health-care systems approve new drugs based on data of safety and efficacy from large randomized clinical trials (RCTs). Strict selection biases and study-entry criteria of subjects included in RCTs often do not reflect those of the population where a therapy is intended to be used. Compliance to treatment in RCTs also differs considerably from real world settings and the relatively small size of most RCTs make them unlikely to detect rare but important safety signals. These and other considerations may explain the gap between evidence generated in RCTs and translating conclusions to health-care policies in the real world. Real-world evidence (RWE) derived from real-world data (RWD) is receiving increasing attention from scientists, clinicians, and health-care policy decision-makers - especially when it is processed by artificial intelligence (AI). We describe the potential of using RWD and AI in Hematology to support research and health-care decisions.

Recent Research Progress of Chiral Small Molecular Antitumor-Targeted Drugs Approved by the FDA From 2011 to 2019

Chiral drugs usually contain chiral centers, which are present as single enantiomers or racemates. Compared with achiral drugs, they have significant advantages in safety and efficacy with high stereoselectivity. Of these drugs, chirality not only exerts influence on the solubility and pharmacokinetic characteristics but also has specific mechanistic characteristics on their targets. We noted that small molecules with unique chiral properties have emerged as novel components of antitumor drugs approved by the FDA in decade. Since approved, these drugs have been continuously explored for new indications, new mechanisms, and novel combinations. In this mini review, recent research progress of twenty-two FDA-approved chiral small molecular-targeted antitumor drugs from 2011 to 2019 is summarized with highlighting the potential and advantages of their applications. We believe that these updated achievements may provide theoretical foundation and stimulate research interests for optimizing drug efficacy, expanding clinical application, overcoming drug resistance, and advancing safety in future clinical administrations of these chiral targeted drugs.

Is there an optimal adjunct therapy to traditional cytotoxic induction?

The traditional cytotoxic induction regimen for acute myeloid leukemia (AML) is seven days of standard-dose cytarabine and three days of an anthracycline antibiotic (such as daunorubicin or idarubicin), commonly known as "7 + 3." Many studies have been conducted to find an additional agent that might improve efficacy. Data from select studies has shown, in certain populations, benefit to adding cladribine, clofarabine and lomustine to a traditional backbone. For mutation-based chemotherapy regimens, midostaurin with 7 + 3 is the current standard of care for FLT3-mutant, younger AML patients. As we learn more about the synergism of molecular agents and traditional anti-cancer treatments, we can hopefully develop novel regimens without abandoning some of the benefits of these mutation agnostic historical therapies.

Harnessing the benefits of available targeted therapies in acute myeloid leukaemia

Research has resulted in regulatory approval of nine agents for acute myeloid leukaemia indications by the US Food and Drug Administration since 2017: the Bcl-2 inhibitor, venetoclax; two FLT3 inhibitors, midostaurin and gilteritinib; two IDH inhibitors, ivosidenib (IDH1 inhibitor) and enasidenib (IDH2 inhibitor); the anti-CD33 antibody-drug conjugate, gemtuzumab ozogamicin; the oral, poorly absorbable hypomethylating agent, azacitidine; the liposomal formulation of cytarabine and daunorubicin (5:1 ratio), CPX-351; and the hedgehog signalling pathway inhibitor, glasdegib. A 100% absorbable oral formulation of the hypomethylating agent decitabine was approved for the treatment of myelodysplastic syndrome and chronic myelomonocytic leukaemia, and might be used as an alternative to parenteral hypomethylating agents. Several of the approvals are as single-agent therapies or in specific combinations for narrow indications, thus offering poor treatment value. In this Review, we discuss ongoing research into combinations containing these commercially available targeted therapies for acute myeloid leukaemia.

The challenge of targets and drug discovery using large-scale screening approaches in onco-hematology

Target identification and drug discovery roads have been widely improved over the past decades in onco-hematology. In this review, we summarize recent improvements in the use of physio-pathologically relevant models and innovative screening approaches to accelerate efficient drug development. Using acute myeloid leukemia as an example, we also discuss the main encountered pitfalls and propose alternative roads to improve the drug discovery journey in onco-hematology.

Evolving Therapeutic Approaches for Older Patients with Acute Myeloid Leukemia in 2021

Simple Summary

The better understanding of disease biology, the availability of new effective drugs and the increased awareness of patients’ heterogeneity in terms of fitness and personal expectations has made the current treatment paradigm of AML in the elderly very challenging. Here, we discuss the evolving criteria used to define eligibility for induction chemotherapy and transplantation, the introduction of new agents in the treatment of patients with very different clinical conditions, the implications of precision medicine and the importance of quality of life and supportive care, proposing a simplified algorithm that we follow in 2021.

Abstract

Acute myeloid leukemia (AML) in older patients is characterized by unfavorable prognosis due to adverse disease features and a high rate of treatment-related complications. Classical therapeutic options range from intensive chemotherapy in fit patients, potentially followed by allogeneic hematopoietic cell transplantation (allo-HCT), to hypomethylating agents or palliative care alone for unfit/frail ones. In the era of precision medicine, the treatment paradigm of AML is rapidly changing. On the one hand, a plethora of new targeted drugs with good tolerability profiles are becoming available, offering the possibility to achieve a prolonged remission to many patients not otherwise eligible for more intensive therapies. On the other hand, better tools to assess patients’ fitness and improvements in the selection and management of those undergoing allo-HCT will hopefully reduce treatment-related mortality and complications. Importantly, a detailed genetic characterization of AML has become of paramount importance to choose the best therapeutic option in both intensively treated and unfit patients. Finally, improving supportive care and quality of life is of major importance in this age group, especially for the minority of patients that are still candidates for palliative care because of very poor clinical conditions or unwillingness to receive active treatments. In the present review, we discuss the evolving approaches in the treatment of older AML patients, which is becoming increasingly challenging following the advent of new effective drugs for a very heterogeneous and complex population.

New Drugs Bringing New Challenges to AML: A Brief Review

The better understanding of the genomic landscape in acute myeloid leukaemia (AML) has progressively paved the way for precision medicine in AML. There is a growing number of drugs with novel mechanisms of action and unique side-effect profiles. This review examines the impact of evolving novel therapies on survival in AML and the challenges that ensue.

Concurrent Diagnosis of Acute Myeloid Leukemia and Symptomatic COVID-19 Infection: a Case Report Successfully Treated with Azacitidine-Venetoclax Combination

SARS-COV2 pandemic has caused profound challenges in health care systems worldwide. Patients affected by hematological neoplasms appear to be particularly at risk of developing COVID-19 complications, with unfavorable outcomes.

Here, we present the case of a 57-years-old woman diagnosed with severe COVID-19 pneumonia and concurrent acute myeloid leukemia (AML). At the time of diagnosis, it was decided to postpone leukemia therapy to enable adequate COVID-19 pneumonia treatment. When her conditions related to pneumonia improved, the combination of Azacitidine-Venetoclax was used as first-line treatment instead of conventional intensive chemotherapy. At the end of the first two cycles, the patient showed complete remission, and a post-remission consolidation with allogeneic hematopoietic stem cell transplantation has been planned.

This case suggests that Azacytidine-Venetoclax induction may represent a valid and safe alternative to intensive chemotherapy in the challenging setting of patients with a concomitant diagnosis of AML and severe COVID-19 infection.

Towards precision medicine for AML

With rapid advances in sequencing technologies, tremendous progress has been made in understanding the molecular pathogenesis of acute myeloid leukaemia (AML), thus revealing enormous genetic and clonal heterogeneity, and paving the way for precision medicine approaches. The successful development of precision medicine for patients with AML has been exemplified by the introduction of targeted FLT3, IDH1/IDH2 and BCL-2 inhibitors. When used as single agents, these inhibitors display moderate antileukaemic activity. However, augmented clinical activity has been demonstrated when they are administered in combination with drugs with broader mechanisms of action targeting epigenetic and/or other oncogenic signalling pathways or with conventional cytotoxic agents. The development of immunotherapies has been hampered by the expression of antigens that are expressed by both leukaemic and non-malignant haematopoietic progenitor cells; nonetheless, a diverse range of immunotherapies are now entering clinical development. This myriad of emerging agents also creates challenges, such as how to safely combine agents with different mechanisms of action, the need to circumvent primary and secondary resistance, and new challenges in future clinical trial design. In this Review, we discuss the current state of precision medicine for AML, including both the potential to improve patient outcomes and the related challenges.

SOHO State of the Art Updates and Next Questions: IDH Inhibition

There has been extraordinary progress in the field of targeted therapy for myeloid malignancies in the last few years, especially due to the approval of various agents that can be used as monotherapy or in combination as first-line treatment or when facing a refractory or relapsed disease. Many successful trials have been conducted recently, and a consistent body of work about the efficacy of novel molecules is now available. In this review, we sought to explain how enasidenib and ivosidenib have changed the face of myeloid neoplasm treatment through isocitrate dehydrogenase inhibition and to summarize the trials results that have led to the current commercial indications for the two molecules.

Genetic identification of patients with AML older than 60 years achieving long-term survival with intensive chemotherapy

To design a simple and reproducible classifier predicting the overall survival (OS) of patients with acute myeloid leukemia (AML) ≥60 years of age treated with 7 + 3, we sequenced 37 genes in 471 patients from the ALFA1200 (Acute Leukemia French Association) study (median age, 68 years). Mutation patterns and OS differed between the 84 patients with poor-risk cytogenetics and the 387 patients with good (n = 13), intermediate (n = 339), or unmeasured (n = 35) cytogenetic risk. TP53 (hazards ratio [HR], 2.49; P = .0003) and KRAS (HR, 3.60; P = .001) mutations independently worsened the OS of patients with poor-risk cytogenetics. In those without poor-risk cytogenetics, NPM1 (HR, 0.57; P = .0004), FLT3 internal tandem duplications with low (HR, 1.85; P = .0005) or high (HR, 3.51; P < 10-4) allelic ratio, DNMT3A (HR, 1.86; P < 10-4), NRAS (HR, 1.54; P = .019), and ASXL1 (HR, 1.89; P = .0003) mutations independently predicted OS. Combining cytogenetic risk and mutations in these 7 genes, 39.1% of patients could be assigned to a "go-go" tier with a 2-year OS of 66.1%, 7.6% to the "no-go" group (2-year OS 2.8%), and 3.3% of to the "slow-go" group (2-year OS of 39.1%; P < 10-5). Across 3 independent validation cohorts, 31.2% to 37.7% and 11.2% to 13.5% of patients were assigned to the go-go and the no-go tiers, respectively, with significant differences in OS between tiers in all 3 trial cohorts (HDF [Hauts-de-France], n = 141, P = .003; and SAL [Study Alliance Leukemia], n = 46; AMLSG [AML Study Group], n = 223, both P < 10-5). The ALFA decision tool is a simple, robust, and discriminant prognostic model for AML patients ≥60 years of age treated with intensive chemotherapy. This model can instruct the design of trials comparing the 7 + 3 standard of care with less intensive regimens.

Updates on targeted therapies for acute myeloid leukaemia

In the past few years research in the underlying pathogenic mechanisms of acute myeloid leukaemia (AML) has led to remarkable advances in our understanding of the disease. Cytogenetic and molecular aberrations are the most important factors in determining response to chemotherapy as well as long-term outcome, but beyond prognostication are potential therapeutic targets. Our increased understanding of the pathogenesis of AML facilitated by next-generation sequencing has spurred the development of new compounds in the treatment of AML, particularly the creation of small molecules that target the disease on a molecular level. Many of the hopeful predictions outlined in our AML review of 2018 are now therapeutic realities: gemtuzumab ozogamicin, venetoclax, FLT3 inhibitors (midostaurin, gilteritinib), IDH inhibitors (ivosidenib, enasidenib), CPX-351, glasdegib, oral decitabine, and oral azacitidine. Others may soon be (quizartinib, APR246 magrolimab, menin inhibitors). The wealth of positive data allows reconsideration of what might soon be new standards of care in younger and older patients with AML. In this review we give an overview of recently approved therapies in AML and address present and future research directions.