Addition of gemtuzumab ozogamicin to induction chemotherapy improves survival in older patients with acute myeloid leukemia

Immunotherapy for Acute Myeloid Leukemia: Allogeneic hematopoietic cell transplantation is here to stay

Acute Myeloid Leukemia (AML) represents 1 % of all new cancer diagnosis made annually in the US and has a five-year survival of 30 %. Traditional treatment includes aggressive induction therapy followed by consolidation therapy that may include a hematopoietic stem cell transplant (HSCT). Thus far, HSCT remains the only potentially curative therapy for many patients with AML owing to the graft-versus-leukemia effect elicited by this treatment. The use of novel therapies, specifically immunotherapy, in the treatment of AML has been limited by the lack of appropriate target antigens, therapy associated toxicities and variable success with treatment. Antigenic variability on leukemia cells and the sharing of antigens by malignant and non-malignant cells makes the identification of appropriate antigens problematic. While studies with immunotherapeutic agents are underway, prior investigations have demonstrated a mixed response with some studies prematurely discontinued due to associated toxicities. This review presents a discussion of the envisioned role of immunotherapy in the treatment of AML in the setting of mixed therapeutic success and potentially lethal toxicities.

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.

Therapeutic Targeting of Acute Myeloid Leukemia by Gemtuzumab Ozogamicin

Acute myeloid leukemia (AML) is a complex hematological malignancy characterized by genetic and clinical heterogeneity and high mortality. Despite the recent introduction of novel pharmaceutical agents in hemato-oncology, few advancements have been made in AML for decades. In the last years, the therapeutic options have rapidly changed, with the approval of innovative compounds that provide new opportunities, together with new challenges for clinicians: among them, on 1 September, 2017 the Food and Drug Administration granted approval for Gemtuzumab Ozogamicin (GO) in combination with daunorubicin and cytarabine for the treatment of adult patients affected by newly diagnosed CD33⁺ AML. Benefits of GO-based regimens were also reported in the pre- and post-transplantation settings. Moreover, several biomarkers of GO response have been suggested, including expression of CD33 and multidrug resistance genes, cytogenetic and molecular profiles, minimal residual disease and stemness signatures. Among them, elevated CD33 expression on blast cells and non-adverse cytogenetic or molecular risk represent largely validated predictors of good response.

Clinical Benefits and Safety of Gemtuzumab Ozogamicin in Treating Acute Myeloid Leukemia in Various Subgroups: An Updated Systematic Review, Meta-Analysis, and Network Meta-Analysis

Background

Previous trials demonstrated evidence involving the total effects of gemtuzumab ozogamicin (GO), an anti-CD33 humanized antibody, on treating acute myeloid leukemia (AML). In this updated systematic review, meta-analysis, and network meta-analysis (NMA), we aimed to comprehensively explore the clinical benefits and safety of GO in various subtypes of AML.

Methods

PubMed, Embase, Cochrane, and Chinese databases were filtered to search randomized controlled trials (RCTs) and retrospective cohort studies that compared clinical efficiency and toxicity of GO with non-GO groups in AML. Random-effects models were used to calculate pooled effect sizes and 95% confidence intervals (CIs). Relative risk (RR) was used for estimating complete remission (CR), early death, and toxicity. Hazard risk (HR) was accomplished to evaluate survival.

Results

Fifteen RCTs and 15 retrospective cohort studies were identified (GO: 4,768; Control: 6,466). GO tended to improve CR (RR 0.95, p = 0.084), followed by significantly improved survival (overall survival: HR 0.86, p = 0.003; event-free survival: HR 0.86, p = 0.015; relapse-free survival: HR 0.83, p = 0.001; cumulative incidence of relapse: HR 0.82, p < 0.001). GO benefits of CR and survival were evident in favorable- and intermediate-risk karyotypes (p ≤ 0.023). GO advantages were also associated with nucleophosmin 1 mutations (p ≤ 0.04), wild-type FMS-like tyrosine kinase 3 internal tandem duplication gene (p ≤ 0.03), age of <70 years (p < 0.05), de novo AML (p ≤ 0.017), and CD33(+) (p ≤ 0.021). Both adding GO into induction therapy (p ≤ 0.011) and a lower (<6 mg/m2) dose of GO (p ≤ 0.03) enhanced survival. Prognosis of combined regimens with GO was heterogeneous in both meta-analysis and NMA, with several binding strategies showing improved prognosis. Additionally, GO was related to increased risk of early death at a higher dose (≥6 mg/m2) (RR 2.01, p = 0.005), hepatic-related adverse effects (RR 1.29, p = 0.02), and a tendency of higher risk for hepatic veno-occlusive disease or sinusoidal obstruction syndrome (RR 1.56, p = 0.072).

Conclusions

These data indicated therapeutic benefits and safety of GO in AML, especially in some subtypes, for which further head-to-head RCTs are warranted.

Systematic Review Registration

[PROSPERO: https://www.crd.york.ac.uk/prospero/], identifier [CRD42020158540].

The long shadow of socioeconomic deprivation over the modern management of acute myeloid leukemia: time to unravel the challenges

Biological and non-biological variables unrelated to acute myeloid leukemia (AML) preclude standard therapy in many settings, with "real world" patients under-represented in clinical trials and prognostic models. Here, using a case-based format, we illustrate the impact that socioeconomic and anthropogeographical constraints can have on optimally managing AML in 4 different healthcare systems. The granular details provided, emphasize the need for the development and targeting of socioeconomic interventions that are commensurate with the changing landscape of AML therapeutics, in order to avoid worsening the disparity in outcomes between patients with biologically similar disease.

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.

3+7 Combined Chemotherapy for Acute Myeloid Leukemia: Is It Time to Say Goodbye?

PURPOSE OF REVIEW

With the recent approval of multiple new drugs for the treatment of acute myeloid leukemia (AML), the relevance of conventional treatment approaches, such as daunorubicin and cytarabine ("3+7") induction chemotherapy, has been challenged. We review the AML risk stratification, the efficacy of the newly approved drugs, and the role of "3+7".

RECENT FINDINGS

Treatment of AML is becoming more niched with specific subtypes more appropriately treated with gemtuzumab, midostaurin, and CPX-351. Although lower intensity therapies can yield high response rates, they are less efficient at preventing relapses. The only curative potential for poor-risk AML is still an allogeneic stem cell transplant. The number of AML subtypes where 3+7 alone is an appropriate therapeutic option is shrinking. However, it remains the backbone for combination therapy with newer agents in patients suitable for intensive chemotherapy.

CD33 Expression and Gentuzumab Ozogamicin in Acute Myeloid Leukemia: Two Sides of the Same Coin

Simple Summary

Roughly 85–90% of adult and pediatric acute myeloid leukemia (AML) are CD33-positive. Gemtuzumab ozogamicin (GO), a humanized murine IgG4 anti-CD33 antibody, is the first target therapy approved in AML therapeutic scenario. This review focuses on current biological information and clinical data from several studies investigating the use of GO in patients with AML. Over the years, flow cytometry, cytogenetics, molecular techniques, and genotyping studies of CD33 SNPs have provided a comprehensive analysis of promising biomarkers for GO responses and have potentially helped to identify subgroups of patients that may benefit from GO addition to standard chemotherapies. Increased understanding of molecular mutations, altered intracellular pathways, and their potential relationship with CD33 expression may open new therapeutic landscapes based on combinatorial regimens in an AML scenario.

Abstract

Acute myeloid leukemia (AML), the most frequent acute leukemia in adults, has been historically treated with infusional cytarabine (ara-c) + daunorubicin (3 + 7) for at least 40 years. The first “target therapy” to be introduced was the monoclonal anti-CD33 gemtuzumab ozogamicin (GO) in 2004. Unfortunately, in 2010 it was voluntarily withdrawn from the market both for safety reasons related to potential liver toxicity and veno-occlusive disease (VOD) and because clinical studies failed to confirm the clinical benefit during induction and maintenance. Seven years later, GO was re-approved based on new data, including insights into its mechanism of action on its target receptor CD33 expressed on myeloid cells. The present review focuses on current biological information and clinical data from several studies investigating GO. Cytogenetic, molecular, and immunophenotypic data are now able to predict the potential positive advantages of GO, with the exception of high-risk AML patients who do not seem to benefit. GO can be considered a ‘repurposed drug’ that could be beneficial for some patients with AML, mostly in combination with new drugs already approved or currently in testing.

Acute Myeloid Leukemia: Historical Perspective and Progress in Research and Therapy Over 5 Decades

With the Food and Drug Administration approval of 9 agents for different acute myeloid leukemia (AML) indications, the prognosis and management of AML is evolving rapidly. Herein, we review the important milestones in the history of AML research and therapy, discuss insights regarding prognostic assessment and prediction of treatment outcome, detail practical supportive care measures, and summarize the current treatment landscape and areas of evolving research.

Gemtuzumab Ozogamicin Improves Event-Free Survival and Reduces Relapse in Pediatric KMT2A-Rearranged AML: Results From the Phase III Children's Oncology Group Trial AAML0531

PURPOSE

We investigated the impact of the CD33-targeted agent gemtuzumab ozogamicin (GO) on survival in pediatric patients with KMT2A-rearranged (KMT2A-r) acute myeloid leukemia (AML) enrolled in the Children's Oncology Group trial AAML0531 (NCT01407757).

METHODS

Patients with KMT2A-r AML were identified and clinical characteristics described. Five-year overall survival (OS), event-free survival (EFS), disease-free survival (DFS), and relapse risk (RR) were determined overall and for higher-risk versus not high-risk translocation partners. GO's impact on response was determined and outcomes based on consolidation approach (hematopoietic stem cell transplant [HSCT] v chemotherapy) described.

RESULTS

Two hundred fifteen (21%) of 1,022 patients enrolled had KMT2A-r AML. Five-year EFS and OS from study entry were 38% and 58%, respectively. EFS was superior with GO treatment (EFS 48% with GO v 29% without, P = .003), although OS was comparable (63% v 53%, P = .054). For patients with KMT2A-r AML who achieved complete remission, GO was associated with lower RR (40% GO v 66% patients who did not receive GO [No-GO], P = .001) and improved 5-year DFS (GO 57% v No-GO 33%, P = .002). GO benefit was observed in both higher-risk and not high-risk KMT2A-r subsets. For patients who underwent HSCT, prior GO exposure was associated with decreased relapse (5-year RR: 28% GO and HSCT v 73% No-GO and HSCT, P = .006). In multivariable analysis, GO was independently associated with improved EFS, improved DFS, and reduced RR.

CONCLUSION

GO added to conventional chemotherapy improved outcomes for KMT2A-r AML; consolidation with HSCT may further enhance outcomes. Future clinical trials should study CD33-targeted agents in combination with HSCT for pediatric KMT2A-r AML.

Immunotherapy in Acute Myeloid Leukemia: Where We Stand

In the past few years, our improved knowledge of acute myeloid leukemia (AML) pathogenesis has led to the accelerated discovery of new drugs and the development of innovative therapeutic approaches. The role of the immune system in AML development, growth and recurrence has gained increasing interest. A better understanding of immunological escape and systemic tolerance induced by AML blasts has been achieved. The extraordinary successes of immune therapies that harness the power of T cells in solid tumors and certain hematological malignancies have provided new stimuli in this area of research. Accordingly, major efforts have been made to develop immune therapies for the treatment of AML patients. The persistence of leukemia stem cells, representing the most relevant cause of relapse, even after allogeneic stem cell transplant (allo-SCT), remains a major hurdle in the path to cure for AML patients. Several clinical trials with immune-based therapies are currently ongoing in the frontline, relapsed/refractory, post-allo-SCT and minimal residual disease/maintenance setting, with the aim to improve survival of AML patients. This review summarizes the available data with immune-based therapeutic modalities such as monoclonal antibodies (naked and conjugated), T cell engagers, adoptive T-cell therapy, adoptive-NK therapy, checkpoint blockade via PD-1/PD-L1, CTLA4, TIM3 and macrophage checkpoint blockade via the CD47/SIRPa axis, and leukemia vaccines. Combining clinical results with biological immunological findings, possibly coupled with the discovery of biomarkers predictive for response, will hopefully allow us to determine the best approaches to immunotherapy in AML.

Allogeneic Stem Cell Transplantation for Acute Myeloid Leukemia: Who, When, and How?

Although the majority of patients with acute myeloid leukemia (AML) treated with intensive chemotherapy achieve a complete remission (CR), many are destined to relapse if treated with intensive chemotherapy alone. Allogeneic stem cell transplant (allo-SCT) represents a pivotally important treatment strategy in fit adults with AML because of its augmented anti-leukemic activity consequent upon dose intensification and the genesis of a potent graft-versus-leukemia effect. Increased donor availability coupled with the advent of reduced intensity conditioning (RIC) regimens has dramatically increased transplant access and consequently allo-SCT is now a key component of the treatment algorithm in both patients with AML in first CR (CR1) and advanced disease. Although transplant related mortality has fallen steadily over recent decades there has been no real progress in reducing the risk of disease relapse which remains the major cause of transplant failure and represents a major area of unmet need. A number of therapeutic approaches with the potential to reduce disease relapse, including advances in induction chemotherapy, the development of novel conditioning regimens and the emergence of the concept of post-transplant maintenance, are currently under development. Furthermore, the use of genetics and measurable residual disease technology in disease assessment has improved the identification of patients who are likely to benefit from an allo-SCT which now represents an increasingly personalized therapy. Future progress in optimizing transplant outcome will be dependent on the successful delivery by the international transplant community of randomized prospective clinical trials which permit examination of current and future transplant therapies with the same degree of rigor as is routinely adopted for non-transplant therapies.

Comparing cure rates for gemtuzumab ozogamicin plus standard chemotherapy vs standard chemotherapy alone in acute myeloid leukemia patients

Aim: Assess the suitability of standard parametric, piecewise and mixture cure models (MCMs) for modeling long-term survival of acute myeloid leukemia patients achieving remission following treatment with gemtuzumab ozogamicin (GO) + standard chemotherapy (SC) or SC alone. MCMs can model survival data comprising of statistically cured (patients in long-term remission) and uncured patients. Materials & methods: Models were fit to patient-level data corresponding to individual treatment arms. Results: Visual inspection showed that MCMs fit the clinical data best. Survival modeling with MCMs showed that treatment with GO + SC versus SC alone results in higher statistical cure rates for event-free survival (rates: 26-35% vs 21-23%) and overall survival (rates: 48-52% vs 38-44%). Conclusion: MCMs are well suited to modeling long-term survival in acute myeloid leukemia patients. Clinical trial registration: NCT00927498 (ClinicalTrials.gov).

Impact of age, functional status, and comorbidities on quality of life and outcomes in elderly patients with AML: review

The incidence of acute myeloid leukemia increases with age, and more than half of AML patients are over 60 years old. Treating elderly AML patients presents several challenges and uncertainties, linked partly to disease characteristics and partly to the difficulty of establishing which patients could benefit from the best treatment. Although some elderly fit patients can receive intensive therapy, many of them are not treated and not enrolled in clinical trials. Yet supportive care is associated with significantly lower survival rates compared to intensive therapy or lower intensive therapy. A poorer prognosis in elderly patients is related to age, functional status, and comorbidities, combined with leukemia characteristics. Chronological age is not the best surrogate factor for selecting patients eligible for intensive chemotherapy. Scoring systems-including patient characteristics (ECOG, comorbidities) and disease characteristics (cytogenetics and molecular parameters)-designed to evaluate probabilities of response to treatment, morbidity, and survival may be used to balance the risk-benefit ratio for intensive therapy. A geriatric assessment (GA) to evaluate physical function, comorbidities, nutritional status, cognitive function, and social support could help identify the most vulnerable patients so that they can receive intensive therapy. A GA would also help take the necessary steps to improve tolerance to treatment. Evaluating markers of fitness and quality of life as part of clinical trials should be favored.

The clinical development of antibody-drug conjugates - lessons from leukaemia

Advances in our understanding of cancer biology have enabled drug development to progress towards better targeted therapies that are both more effective and safer owing to their lack of off-target toxicities. In this regard, antibody-drug conjugates (ADCs), which have the potential to combine the selectivity of therapeutic antibodies with the cytotoxicity of highly toxic small molecules, are a rapidly developing drug class. The complex and unique structure of an ADC, composed of a monoclonal antibody conjugated to a potent cytotoxic payload via a chemical linker, is designed to selectively target a specific tumour antigen. The success of an ADC is highly dependent on the specific properties of its components, all of which have implications for the stability, cytotoxicity, pharmacokinetics and antitumour activity of the ADC. The development of therapeutic ADCs, including gemtuzumab ozogamicin and inotuzumab ozogamicin, provided great knowledge of the refinements needed for the optimization of such agents. In this Review, we describe the key components of ADC structure and function and focus on the clinical development and subsequent utilization of two leukaemia-directed ADCs - gemtuzumab ozogamicin and inotuzumab ozogamicin - as well as on the mechanisms of resistance and predictors of response to these two agents.

Unintended Regulatory Caused Early Death-A Difficult Endpoint in Cancer Patient Care and Treatment

Simple Summary

This is a position paper by a clinical oncologist. It voices concerns about political decision making and regulatory time frames for drug availability, both of which are critical for patient care in life-threatening diseases such as cancer.

Abstract

The pharmacological armory against cancer has been growing, with many new drugs approved. The Good Clinical Practice (GCP)-based Clinical Trials Directive was adopted in the EU in 2001, with the important objectives of achieving better patient safety and improved quality of clinical trial conduct. However, clinical experience with the implementation of the regulation raises the question as to whether aspects of this regulatory framework can cause harm to some patients. This question also arises in daily clinical cancer patient care when the time between the publication of pivotal study results and their approval, and details of post-approval regulations, are scrutinized. Clinical observations, provocatively summarized as “unintended regulatory caused early death”, are discussed.

Acute myeloid leukemia: Treatment and research outlook for 2021 and the MD Anderson approach

The unraveling of the pathophysiology of acute myeloid leukemia (AML) has resulted in rapid translation of the information into clinical practice. After more than 40 years of slow progress in AML research, the US Food and Drug Administration has approved nine agents for different AML treatment indications since 2017. In this review, we detail the progress that has been made in the research and treatment of AML, citing key publications related to AML research and therapy in the English literature since 2000. The notable subsets of AML include acute promyelocytic leukemia (APL), core-binding factor AML (CBF-AML), AML in younger patients fit for intensive chemotherapy, and AML in older/unfit patients (usually at the age cutoff of 60-70 years). We also consider within each subset whether the AML is primary or secondary (therapy-related, evolving from untreated or treated myelodysplastic syndrome or myeloproliferative neoplasm). In APL, therapy with all-trans retinoic acid and arsenic trioxide results in estimated 10-year survival rates of ≥80%. Treatment of CBF-AML with fludarabine, high-dose cytarabine, and gemtuzumab ozogamicin (GO) results in estimated 10-year survival rates of ≥75%. In younger/fit patients, the "3+7" regimen (3 days of daunorubicin + 7 days of cytarabine) produces less favorable results (estimated 5-year survival rates of 35%; worse in real-world experience); regimens that incorporate high-dose cytarabine, adenosine nucleoside analogs, and GO are producing better results. Adding venetoclax, FLT3, and IDH inhibitors into these regimens has resulted in encouraging preliminary data. In older/unfit patients, low-intensity therapy with hypomethylating agents (HMAs) and venetoclax is now the new standard of care. Better low-intensity regimens incorporating cladribine, low-dose cytarabine, and other targeted therapies (FLT3 and IDH inhibitors) are emerging. Maintenance therapy now has a definite role in the treatment of AML, and oral HMAs with potential treatment benefits are also available. In conclusion, AML therapy is evolving rapidly and treatment results are improving in all AML subsets as novel agents and strategies are incorporated into traditional AML chemotherapy. LAY SUMMARY: Ongoing research in acute myeloid leukemia (AML) is progressing rapidly. Since 2017, the US Food and Drug Administration has approved 10 drugs for different AML indications. This review updates the research and treatment pathways for AML.

Acute myeloid leukemia: current progress and future directions

Progress in the understanding of the biology and therapy of acute myeloid leukemia (AML) is occurring rapidly. Since 2017, nine agents have been approved for various indications in AML. These included several targeted therapies like venetoclax, FLT3 inhibitors, IDH inhibitors, and others. The management of AML is complicated, highlighting the need for expertise in order to deliver optimal therapy and achieve optimal outcomes. The multiple subentities in AML require very different therapies. In this review, we summarize the important pathophysiologies driving AML, review current therapies in standard practice, and address present and future research directions.

Treatment options for older unfit patients with acute myeloid leukemia

Older acute myeloid leukemia patients usually experience a bleak outcome, especially those in the unfit group. For this unfit category, intensive chemotherapy and allogeneic stem cell transplantation are usually accompanied by higher early mortality, which results from higher risk genetic profiles and worse psychological and physiological conditions. The significant improvement in genetic technology recently has driven the appearance of several mutation-targeted therapies, such as FLT3, Bcl-2, IDH and Hedgehog pathway inhibitors and an anti-CD33 antibody-drug conjugate, which have changed enormously the therapeutic landscape of acute myeloid leukemia. This review describes the treatment dilemma of the unfit group and discusses the objective clinical data of each targeted drug and mechanisms of resistance, with a focus on combination strategies with fewer toxicities and abrogation of drug resistance.

Budget Impact Analysis of Gemtuzumab Ozogamicin for the Treatment of CD33-Positive Acute Myeloid Leukemia

BACKGROUND

Gemtuzumab ozogamicin (GO) was approved in 2017 in the US for the treatment of adults with newly diagnosed CD33-positive (CD33+) acute myeloid leukemia (AML), and adults and pediatric patients with CD33+ relapsed/refractory (R/R) AML.

OBJECTIVE

The aim of this study was to estimate the budgetary impact of introducing GO to a 1-million-member US health plan over a 5-year period.

METHODS

We developed models to estimate the impact of introducing GO in combination with conventional induction chemotherapy or as monotherapy for newly diagnosed AML, and as monotherapy for R/R AML. Models were built using data on drug costs and treatment-related outcomes obtained from published clinical trials and other publicly available sources. Results were reported on a per member/per year and per member/per month (PMPM) basis.

RESULTS

Base-case results of the newly diagnosed model indicated that the addition of GO in the combination setting reduced the overall budget of a 1-million-member health plan. The estimated net cost (US$) savings ranged from $72,969 ($0.006 PMPM) in year 1 to $745,426 ($0.062 PMPM) in year 5. In the monotherapy setting, GO was associated with increased net costs ranging from $4118 (0.0003 PMPM) in year 1 to $31,885 ($0.003 PMPM) in year 5. Base-case results of the R/R AML model demonstrated increased net costs that ranged from $17,326 ($0.001 PMPM) in year 1 to $46,163 ($0.004 PMPM) in year 5. Scenario analyses in all settings indicated the budget impact was not overly sensitive to the selected input assumptions, with the exception of the scenario considering only the pharmacy budget impact in the combination setting.

CONCLUSIONS

The introduction of GO for newly diagnosed and R/R AML would have a minimal impact on the budget of a US health plan and could result in cost savings in the combination therapy setting for newly diagnosed AML.

Clinical outcomes of gemtuzumab ozogamicin for relapsed acute myeloid leukemia: single-institution experience

We retrospectively evaluated the clinical efficacy and toxicity of gemtuzumab ozogamicin (GO) in patients with relapsed acute myeloid leukemia (AML). Nineteen patients (median 70 years) received GO (9 mg/m², days 1 and 15) as salvage therapy in our institution between 2006 and 2017. The primary endpoint was the response rate. The secondary endpoint was the occurrence of adverse events. Thirteen patients had de novo AML, and 6 patients had secondary AML. Most of the patients had received salvage treatments more than once prior to GO. Six patients responded to the treatment (31.6%) with 3 complete remissions (15.8%). Five patients had stable disease, and 8 patients did not show any response. GO was more efficacious among the patients with fewer numbers of prior salvage treatments. CD33 positivity of leukemic cells was higher in responders than in nonresponders. Peripheral WT1 mRNA levels mostly decreased over time in the responders. The adverse event most commonly seen was febrile neutropenia (84%). No patient presented with veno-occlusive disease. Three patients died by day 30 (mortality rate 15.8%), one due to acute respiratory distress syndrome and the other two due to sepsis. GO remains an effective salvage treatment.

Multilineage Dysplasia as Assessed by Immunophenotype in Acute Myeloid Leukemia: A Prognostic Tool in a Genetically Undefined Category

Simple Summary

The prognostic role of multi-lineage dysplasia is still debated in acute myeloid leukemia. The aim of our work was to study dysplasia by a technique alternative to the conventional morphological method, which is multi-parameter flow cytometry. To this end, we used an immune-phenotypic score (IPS), able to estimate dysplasia by the extent of deviation from normal profile, obtained in a control group. IPS provided no insight into prognosis when considered overall nor within well-defined genetic categories. Of interest, IPS-related dysplasia conveyed significant prognostic information when we focused on genetically undefined patients, triple-negative for NPM1, FLT3 and CEBPA. This category still represents a non-negligible fraction of patients, that lack specific molecular features either for targeted drugs or for proper risk assessment. In this context, our data could help address the relative unmet needs in treatment strategy, and provide insight into response prediction in the rapidly evolving therapeutic scenario of AML.

Abstract

Acute myeloid leukemia (AML) “with myelodysplasia-related changes (MRC)” is considered a separate entity by the World Health Organization (WHO) classification of myeloid neoplasms. While anamnestic and cytogenetic criteria provide objective attribution to this subset, with clear unfavorable prognostic significance, the actual role of multi-lineage dysplasia (MLD) as assessed by morphology is debated. The aim of our work was to study MLD by a technique alternative to morphology, which is multiparameter flow cytometry (MFC), in a large series of 302 AML patients intensively treated at our Center. The correlation with morphology we observed in the unselected analysis reiterated the capability of the MFC-based approach at highlighting dysplasia. MLD data, estimated through an immune-phenotypic score (IPS), provided no insight into prognosis when considered overall nor within well-defined genetic categories. Of interest, IPS-related dysplasia conveyed significant prognostic information when we focused on genetically undefined patients, triple-negative for NPM1, FLT3 and CEBPA (TN-AML). In this context, the lack of dysplastic features (IPS_0) correlated with a significantly higher CR rate and longer survival compared to patients showing dysplasia in one or both (neutrophil and erythroid) cell lineages. The impact of IPS category maintained its validity after censoring at allogeneic HSCT and in a multivariate analysis including baseline and treatment-related covariates. In a subgroup featured by the lack of genetic determinants, our data could help address the relative unmet needs in terms of risk assessment and treatment strategy, and provide insight into prediction of response in the rapidly evolving therapeutic scenario of AML.

Prevention, recognition, and management of adverse events associated with gemtuzumab ozogamicin use in acute myeloid leukemia

Gemtuzumab ozogamicin (GO), a humanized anti-CD33 monoclonal antibody conjugated to the cytotoxic antibiotic agent calicheamicin, is approved for the treatment of newly-diagnosed CD33 + AML in adults and children ≥ 1 month old, and relapsed or refractory CD33 + AML in adults and children ≥ 2 years old. GO treatment has been associated with an increased risk of hepatotoxicity and hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS), especially following hematopoietic stem cell transplantation. Other non-specific serious adverse events (SAEs) associated with GO treatment are myelosuppression, bleeding/thrombocytopenia, infusion-related reaction, and tumor lysis syndrome. This report summarizes an expert panel of physicians' recommendations for the evaluation and management of SAEs following GO, emphasizing the prevention and management of VOD/SOS.

Gemtuzumab ozogamicin for the treatment of acute myeloid leukemia in adults

INTRODUCTION

Treatment of acute myeloid leukemia (AML) has changed dramatically in the past ten years with the approval of targeted agents, the first of which was the anti-CD33 antibody-drug conjugate gemtuzumab ozogamicin (GO). Despite withdrawal from the market after accelerated approval, GO was reapproved and now has a well-established role in treating select AML patients. CD33 has proven to be an important target for drug development in AML as evidenced by the improvement in survival with GO treatment.

AREAS COVERED

The review summarizes the development of GO, its mechanism of action, initial studies and approval, withdrawal from the market, and subsequent reapproval after the results of several large randomized studies became available. We also provide an overview of its current role in the treatment landscape of AML.

EXPERT OPINION

Multiple phase 3 trials with GO have established a significant benefit with GO in induction therapy for favorable risk AML. Additional studies support the use of GO in relapsed/refractory AML and APL. Despite the withdrawal of GO from the market after initial approval, GO has proven to improve survival of select AML patients when added to induction chemotherapy and in relapsed disease.

Gemtuzumab ozogamicin in acute myeloid leukemia: past, present and future

After being in the therapeutic wilderness for several decades, acute myeloid leukemia has been recently thrust into the limelight with a series of drug approvals. Technical refinements in production, genetic manipulation and chemical modification of monoclonal antibodies led to growing interest in antibodies-based treatment strategies. Much of the focus of these efforts in acute myeloid leukemia has been on CD33 as a target. On September 2, 2017, the U.S. Food and Drug Administration approved gemtuzumab ozogamicin for treatment of relapsed or refractory CD33⁺ acute myeloid leukemia. This signals a new chapter in the long and unusual story of gemtuzumab ozogamicin, which was the first antibody-drug conjugate approved for human use by the Food and Drug Administration. In this review we have analyzed the history of this drug which, among several mishaps, is experiencing a second youth and still represents a field to be further explored.

Nuclear Receptors as Potential Therapeutic Targets for Myeloid Leukemia

The nuclear receptor (NR) superfamily has been studied extensively in many solid tumors and some receptors have been targeted to develop therapies. However, their roles in leukemia are less clear and vary considerably among different types of leukemia. Some NRs participate in mediating the differentiation of myeloid cells, making them attractive therapeutic targets for myeloid leukemia. To date, the success of all-trans retinoic acid (ATRA) in treating acute promyelocytic leukemia (APL) remains a classical and unsurpassable example of cancer differentiation therapy. ATRA targets retinoic acid receptor (RAR) and forces differentiation and/or apoptosis of leukemic cells. In addition, ligands/agonists of vitamin D receptor (VDR) and peroxisome proliferator-activated receptor (PPAR) have also been shown to inhibit proliferation, induce differentiation, and promote apoptosis of leukemic cells. Encouragingly, combining different NR agonists or the addition of NR agonists to chemotherapies have shown some synergistic anti-leukemic effects. This review will summarize recent research findings and discuss the therapeutic potential of selected NRs in acute and chronic myeloid leukemia, focusing on RAR, VDR, PPAR, and retinoid X receptor (RXR). We believe that more mechanistic studies in this field will not only shed new lights on the roles of NRs in leukemia, but also further expand the clinical applications of existing therapeutic agents targeting NRs.

Acute Myeloid Leukemia, Version 3.2019, NCCN Clinical Practice Guidelines in Oncology

Acute myeloid leukemia (AML) is the most common form of acute leukemia among adults and accounts for the largest number of annual deaths due to leukemias in the United States. Recent advances have resulted in an expansion of treatment options for AML, especially concerning targeted therapies and low-intensity regimens. This portion of the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for AML focuses on the management of AML and provides recommendations on the workup, diagnostic evaluation and treatment options for younger (age <60 years) and older (age ≥60 years) adult patients.

Novel Treatment Paradigms in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a heterogeneous disease marked by the presence of several driver mutations and molecular subgroups even in a single patient. The genetic and molecular heterogeneity is also reflected by a progressive shift from a morphologic classification to one informed by causative genomic changes. Cytogenetic results and somatic mutations are increasingly being utilized to guide use of intensive chemotherapy and low-intensity chemotherapy, particularly among older adults. Utilization of next-generation sequencing in AML has led to increasing use of targeted treatments for actionable mutations. Quantitative real-time polymerase chain reaction-based mutational analysis and multicolor flow cytometry offer sensitive assays that can detect minimal residual disease (MRD). Several studies have shown that MRD negativity, as defined by specified cutoff values, is highly prognostic with potential therapeutic implications. The last 3 years mark an unprecedented history in the drug development in AML with approval of 8 new drugs and large portfolio of ongoing early and late-phase trials of several promising drugs. Multiple combinatorial trials of approved agents and approval of newer agents in the future will continue to change the therapeutic landscape of AML.

Biomarkers of Gemtuzumab Ozogamicin Response for Acute Myeloid Leukemia Treatment

Gemtuzumab ozogamicin (GO, Mylotarg®) consists of a humanized CD33-targeted antibody-drug conjugated to a calicheamicin derivative. Growing evidence of GO efficacy in acute myeloid leukemia (AML), demonstrated by improved outcomes in CD33-positive AML patients across phase I to III clinical trials, led to the Food and Drug Administration (FDA) approval on 1 September 2017 in CD33-positive AML patients aged 2 years and older. Discrepancies in GO recipients outcome have raised significant efforts to characterize biomarkers predictive of GO response and have refined the subset of patients that may strongly benefit from GO. Among them, CD33 expression levels, favorable cytogenetics (t(8;21), inv(16)/t(16;16), t(15;17)) and molecular alterations, such as NPM1, FLT3-internal tandem duplications and other signaling mutations, represent well-known candidates. Additionally, in depth analyses including minimal residual disease monitoring, stemness expression (LSC17 score), mutations or single nucleotide polymorphisms in GO pathway genes (CD33, ABCB1) and molecular-derived scores, such as the recently set up CD33_PGx6_Score, represent promising markers to enhance GO response prediction and improve patient management.

Management of Acute Myeloid Leukemia (AML) in Older Patients

PURPOSE OF REVIEW

The acute myeloid leukemia (AML) treatment landscape has rapidly evolved over the past few years. These changes have several implications for the care of older adults (≥ 60 years), who have inferior clinical outcomes. We review decision-making in older adults, focusing on patient- and disease-related factors. We then summarize current treatment options, including multiple recently approved therapies, based on hypothetical clinical scenarios.

RECENT FINDINGS

In lieu of using chronological age to determine fitness, we highlight the importance of standardized fitness assessments using geriatric assessments. Next, we review intensive and lower-intensity treatment options in the upfront setting. We focus on multiple newly approved medications, including venetoclax, midostaurin, CPX-351, gemtuzumab, glasdegib, enasidenib, and ivosidenib, and their specific indications. Lastly, we briefly discuss supportive care of older adults with AML. Outcomes of older adults with AML remain poor; fortunately, there are many new promising treatment options. Personalized treatment plans based on patient- and disease-specific factors are essential to the care of older adults with AML.

Which are the most promising targets for minimal residual disease-directed therapy in acute myeloid leukemia prior to allogeneic stem cell transplant?

Minimal residual disease has emerged as an important prognostic factor for relapse and survival in acute myeloid leukemia. Eradication of minimal residual disease may increase the number of patients with long-term survival; however, to date, strategies that specifically target minimal residual disease are limited. Consensus guidelines on minimal residual disease detection by immunophenotypic and molecular methods are an essential initial step for clinical trials evaluating minimal residual disease. Here, we review promising targets of minimal residual disease prior to allogeneic stem cell transplantation. Specifically, the focus of this review is on the rationale and clinical development of therapies targeting: oncogenic driver mutations, apoptosis, methylation, and leukemic immune targets. We review the progress made in the clinical development of therapies against each target and the challenges that lie ahead.

Benchmarking treatment effects for patients over 70 with acute myeloid leukemia: A systematic review and meta-analysis

OBJECTIVES

The majority of patients with acute myeloid leukemia (AML) are aged 70 and over. However, there is uncertainty about how and whether older patients with AML should receive cytotoxic treatment.

MATERIALS AND METHODS

Medline and Cochrane library search was performed for studies in newly diagnosed AML which enrolled at least 20 patients per arm (for randomized controlled trials), or 50 patients (for non-randomized studies) over the age of 70. References were hand searched for additional eligible studies. Study investigators were contacted to maximize relevant data. Dual independent data extraction was done using standardized data collection forms. Data was collected on study and treatment characteristics, baseline patient information, and outcomes. Study methodological quality was assessed. The primary outcome was 1 year overall survival (OS). Impact of treatment [intensive chemotherapy (INT), low-dose chemotherapy (LOW), hypomethylating agents (HMA), or best supportive care (BSC)], cytogenetics, performance status, and comorbidity were assessed.

RESULTS

The search produced 11,846 references of which 38 randomized controlled trials and 30 non-randomized studies met inclusion criteria, representing 13,381 patients, with a worldwide distribution. One-year OS with INT was 37% (31-42%), with LOW 11% (6-18%), with HMA 35% (18-54%) and with BSC 17%(13-21%). Two-year OS was 22% (18-26%), 11% (7-15%), 22% (16-28%), 6% (2-12%), respectively. We present subgroup data based on the studies including cytogenetics, performance status, and comorbidity. Formal direct comparisons with adjustment for all prognostic factors were not possible.

CONCLUSIONS

In this largest to date series of AML patients aged 70 and older, we provide benchmarks for treatment efficacy and effectiveness that may be used for decision analysis models and for the future development of clinical trials focusing on these patients.

Safety of gemtuzumab ozogamicin as monotherapy or combination therapy in an expanded-access protocol for patients with relapsed or refractory acute myeloid leukemia

Gemtuzumab ozogamicin (GO) remained available to US clinicians through an open-label expanded-access protocol (NCT02312037) until GO was reapproved. Patients were aged ≥3 months with relapsed/refractory (R/R) acute myeloid leukemia (AML), high-risk myelodysplastic syndrome, or acute promyelocytic leukemia (APL), and had exhausted other treatment options. Three hundred and thirty one patients received GO as monotherapy for R/R AML (n = 139), combination therapy for R/R AML (n = 183), or treatment for R/R APL (n = 9). Corresponding treatment discontinuations occurred in 68, 39, and 33% of patients. All-causality grade 5 AEs occurred in 52, 22, and 22% of patients in the monotherapy, combination, and APL groups, respectively. Corresponding grades 3 and 4 treatment-related AEs were reported in 60, 55 and 78% of patients. Hepatotoxicity occurred in five patients: veno-occlusive disease (n = 4) and drug-induced liver injury (n = 1). GO was generally well tolerated in patients with R/R AML or APL. Most frequent treatment-related grade ≥3 AEs were hematologic AEs.Clinicaltrials.gov identifier: NCT02312037.

Shifting therapeutic paradigms in induction and consolidation for older adults with acute myeloid leukemia

PURPOSE OF REVIEW

As the age and life expectancy of the general population rise, the number of acute myeloid leukemia (AML) patients suitable for therapy is expected to dramatically increase. The population of older adults with AML, while already comprising the vast majority of AML patients, has not been specifically addressed in terms of unique age-related features, such as existence of comorbidities, frailty, and disease biology.

RECENT FINDINGS

Over the past decade, major improvements in the approach to the management of older adults with AML included: incorporation of new comorbidity scores specifically oriented to this patient population that can predict individual fitness to treatment, refined knowledge of the unique mutational landscape, and incorporating new combinations and novel agents designed to target the AML biology. Particularly, the recent exciting description of age-related clonal hematopoiesis and its evolution to AML may open new avenues for intervention prior to development of full-blown leukemia.

SUMMARY

The rising awareness of the unique biology and special needs of older adults with AML has resulted in the design of new studies aiming to target the aberrant mutations and clinical characteristics in this patient population.

How we treat older patients with acute myeloid leukaemia

After decades when intensive chemotherapy remained the only effective anti-acute myeloid leukaemia (AML) treatment, a torrent of novel, less toxic agents are about to revolutionise AML therapy. Prolonged remissions with good quality of life become achievable for many patients previously considered only for palliative care because they could not tolerate intensive therapy. As treatment options multiply, the importance of genetic profile is recognised, even for advanced-age patients for whom cure is unlikely. With lack of randomised comparative trials for most treatment regimens, one can only extrapolate data from existing studies to make evidence-based decisions. We herein present seven common clinical scenarios illustrating the complexity of treating older AML patients and describe our approach to their management. In each case, up-to-date data on relevant agents to be offered to a particular patient are discussed. The current review is limited to the drugs, available and approved in the Western world and many promising agents, still under investigation, are not discussed.

Immune escape and immunotherapy of acute myeloid leukemia

In spite of the recent approval of new promising targeted therapies, the clinical outcome of patients with acute myeloid leukemia (AML) remains suboptimal, prompting the search for additional and synergistic therapeutic rationales. It is increasingly evident that the bone marrow immune environment of AML patients is profoundly altered, contributing to the severity of the disease but also providing several windows of opportunity to prompt or rewire a proficient antitumor immune surveillance. In this Review, we present current evidence on immune defects in AML, discuss the challenges with selective targeting of AML cells, and summarize the clinical results and immunologic insights from studies that are testing the latest immunotherapy approaches to specifically target AML cells (antibodies, cellular therapies) or more broadly reactivate antileukemia immunity (vaccines, checkpoint blockade). Given the complex interactions between AML cells and the many components of their environment, it is reasonable to surmise that the future of immunotherapy in AML lies in the rational combination of complementary immunotherapeutic strategies with chemotherapeutics or other oncogenic pathway inhibitors. Identifying reliable biomarkers of response to improve patient selection and avoid toxicities will be critical in this process.

The efficacy and toxicity of induction chemotherapy plus concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma: A meta-analysis of randomized controlled trials

BACKGROUND

A systemic review and meta-analysis of randomized controlled trials (RCTs) was performed to compare the efficacy, toxicity and safety of concurrent chemoradiotherapy (CCRT) with or without induction chemotherapy (IC) for locoregionally advanced nasopharyngeal carcinoma (NPC).

METHODS

Research searching was performed in Web of Science, PubMed, The Cochrane Library, Embase, Chinese Biomedical Database, Chinese National Knowledge Infrastructure, Chongqing VIP Database for Chinese Technical Periodicals and Wanfang Database. RCTs including patients diagnosed with locoregionally advanced NPC without metastasis and randomly treated with IC plus CCRT and CCRT alone were included. Survival and outcome data were extracted and meta-analysis was performed using the Revman 5.3.0 software.

RESULTS

Ten RCTs (2280 patients) were selected and used for pooled meta-analysis. In comparison with CCRT, IC plus CCRT treatment significantly improved the overall survival (OS; HR = 0.70, 95%CI 0.56-0.87, P = .002), progression-free survival (PFS; HR = 0.75, 95%CI 0.65-0.87, P < .0001), distant metastasis failure-free survival (DMFS; HR = 0.71, 95%CI 0.58-0.85, P = .0003) and loco-regional failure-free survival (LFES; HR = 0.72, 95%CI 0.59-0.88, P = .002) of patients with locoregionally advanced NPC. Patients treated with IC and CCRT had higher incidence of grade 3-4 leucopenia and thrombocytopenia than patients treated with CCRT alone (P < .0001). No significant difference in other grade 3-4 adverse events and radiation toxicity was observed between the two groups. IC combined with CCRT improved the survival of patients with locoregionally advanced NPC.

CONCLUSIONS

Combined IC and CCRT therapy was an efficacy treatment regimen for locoregionally advanced NPC.

Mutational profile and benefit of gemtuzumab ozogamicin in acute myeloid leukemia

Acute myeloid leukemia (AML) is a highly heterogeneous disease both in terms of genetic background and response to chemotherapy. Although molecular aberrations are routinely used to stratify AML patients into prognostic subgroups when receiving standard chemotherapy, the predictive value of the genetic background and co-occurring mutations remains to be assessed when using newly approved antileukemic drugs. In the present study, we retrospectively addressed the question of the predictive value of molecular events on the benefit of the addition of gemtuzumab ozogamicin (GO) to standard front-line chemotherapy. Using the more recent European LeukemiaNet (ELN) 2017 risk classification, we confirmed that the benefit of GO was restricted to the favorable (hazard ratio [HR], 0.54, 95% confidence interval [CI], 0.30-0.98) and intermediate (HR, 0.57; 95% CI, 0.33-1.00) risk categories, whereas it did not influence the outcome of patients within the adverse risk subgroup (HR, 0.93; 95% CI, 0.61-1.43). Interestingly, the benefit of GO was significant for patients with activating signaling mutations (HR, 0.43; 95% CI, 0.28-0.65), which correlated with higher CD33 expression levels. These results suggest that molecular aberrations could be critical for future differentially tailored treatments based on integrated genetic profiles that are able to predict the benefit of GO on outcome.

The Time Has Come for Targeted Therapies for AML: Lights and Shadows

Acute myeloid leukemia (AML) is a complex disease characterized by genetic and clinical heterogeneity and high mortality. After 40 years during which the standard of care for patients evolved very little, the therapeutic landscape has recently seen rapid changes, with the approval of eight new drugs by the Food and Drug Administration (FDA) within the last 2 years, providing new opportunities, as well as new challenges, for treating clinicians. These therapies include FLT3 inhibitors midostaurin and gilteritinib, CPX-351 (liposomal cytarabine and daunorubicin), gemtuzumab ozogamicin (GO, anti-CD33 monoclonal antibody conjugated with calicheamicin), IDH1/IDH2 inhibitors ivosidenib and enasidenib, Hedgehog inhibitor glasdegib, and BCL-2 inhibitor venetoclax. In this review, we summarize currently available data on these new drugs and discuss the rapidly evolving therapeutic armamentarium for AML, focusing on targeted therapies.

Reinforcing the primary immunotherapy modulators against acute leukemia; monoclonal antibodies in AML

Recent therapeutic advances in cancer treatment recruit immune system potentiation against malignant cells. Numerous ongoing clinical trials on immunotherapy methods, either monotherapy or combination therapy, are investigating the impeding factors on the way of acute myeloid leukemia (AML) treatment. Due to the genetic diversity in AML progenitors, combining various strategies is more likely to be useful for improving patient outcomes. This review describes the details of applying monoclonal antibodies against AML, focusing on CD33, CD123, FLT3, CD45 and CD66 targeting. Furthermore, it clarifies the importance of immunotoxins, bispecific antibodies, chimeric antigen receptor (CAR)-T cells and T cell receptor-modified cells as reinforcing agents for monoclonal antibodies.

Single-agent and combination biologics in acute myeloid leukemia

Acute myeloid leukemia (AML) is a heterogeneous malignancy characterized by recurrent genetic, epigenetic, and metabolic abnormalities. As a result of our increasing knowledge of the underlying biology of AML leading to rational drug development, several new targeted agents have been recently added to our therapeutic arsenal. The BCL2 inhibitor venetoclax in combination with low-dose cytarabine (LDAC) or hypomethylating agents (HMAs) is safe and effective in older patients with newly diagnosed AML ineligible for intensive chemotherapy. Glasdegib, a hedgehog pathway inhibitor, may be used in combination with LDAC for the same indication and improves survival compared with LDAC alone. In newly diagnosed, fit, older patients with therapy-related AML or AML with myelodysplasia-related changes, the liposome-encapsulated combination of daunorubicin and cytarabine (CPX-351) has shown superiority over the 7 + 3 regimen. The presence of an IDH1 or IDH2 mutation can be effectively targeted by ivosidenib or enasidenib, respectively. Gemtuzumab ozogamicin improves event-free survival in CD33+ patients with favorable or intermediate-risk cytogenetics. With new targeted agents available, comprehensive genomic characterization of AML at diagnosis and relapse is increasingly necessary to select optimal treatment. Herein, we review the new single-agent and combination biologics (omitting FLT3 inhibitors, which are discussed separately) and provide recommendations on how to best use and manage patients on these regimens in clinical practice.

Gemtuzumab ozogamicin and novel antibody-drug conjugates in clinical trials for acute myeloid leukemia

Targeted agents are increasingly used for the therapy of acute myeloid leukemia (AML). Gemtuzumab ozogamicin (GO) is the first antibody-drug conjugate (ADC) approved for induction therapy of AML. When used in fractionated doses, GO combined with the conventional cytarabine/anthracycline-based induction chemotherapy significantly improves the outcome of previously untreated AML patients. Single-agent GO is effective and safe for AML patient ineligible for intensive chemotherapy. Multiple combination regimens incorporating GO have also been recommended as potential alternative options. In addition, several novel ADCs targeting CD33, CD123 and CLL-1 are currently undergoing preclinical or early clinical investigations. In this review, we summarized the efficacy and limitations of GO as well as novel ADCs for adult AML patients.

CPX-351 (vyxeos) in AML

For decades, the standard induction for patients with acute myeloid leukemia (AML) has been the combination of cytarabine with anthracycline (7 + 3 regimen). In August 2017 the US FDA approved CPX-351 (vyxeos), a liposomal formulation of cytarabine and daunorubicin at a fixed 5:1 molar ratio, for the treatment of adults with newly diagnosed AML with myelodysplasia-related changes (AML-MRC) and therapy-related AML (t-AML). This is the first approved treatment specifically for patients with this subgroup of AML. The approval was based on findings from a multicenter, randomized, open-label, phase III study of CPX-351 Versus 7 + 3 in patients 60-75 years old with newly diagnosed AML-MRC or t-AML. In this study CPX-351 had a higher median OS than 7 + 3 (9.56 vs 5.95 months, HR 0.69; 95% CI: 0.52 to 0.90, p = 0.005). In this profile, we review preclinical and clinical data, and discuss limitations and future directions with CPX-351 use in AML.