A randomized study of decitabine versus conventional care for maintenance therapy in patients with acute myeloid leukemia in complete remission

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

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

Survival outcomes in patients with acute myeloid leukaemia who received subsequent therapy for relapse in QUAZAR AML-001

In the phase 3 QUAZAR AML-001 trial (NCT01757535) of patients with acute myeloid leukaemia (AML) in remission following intensive chemotherapy (IC) and ineligible for haematopoietic stem cell transplant (HSCT), oral azacitidine (Oral-AZA) maintenance significantly prolonged overall survival (OS) versus placebo. The impact of subsequent treatment following maintenance has not been evaluated. In this post hoc analysis, OS was estimated for patients who received subsequent AML therapy, and by regimen received (IC or lower-intensity therapy). First subsequent therapy (FST) was administered after treatment discontinuation in 134/238 Oral-AZA and 173/234 placebo patients. OS from randomization in patients who received FST after Oral-AZA versus placebo was 17.8 versus 12.9 months (HR: 0.82 [95% CI: 0.64-1.04], median follow-up: 56.7 months); OS from FST was similar between arms. Among patients who received injectable hypomethylating agents as FST, median OS was 8.2 versus 4.9 months in the Oral-AZA versus placebo groups (HR: 0.66 [95% CI: 0.41-1.06]). Forty-eight patients (16/238 Oral-AZA, 32/234 placebo) received HSCT following treatment discontinuation, including six Oral-AZA patients still in first remission; Oral-AZA OS benefit persisted when censoring these patients. Oral-AZA maintenance can prolong AML remission duration without negatively impacting survival outcomes after salvage therapies.

Efficacy of Yisui granule on myelodysplastic syndromes in SKM-1 mouse xenograft model through suppressing Wnt/β-catenin signaling pathway

OBJECTIVE

To unmask the underlying mechanisms of Yisui granule (, YSG) for the treatment of Myelodysplastic syndromes (MDS).

METHODS

Our study used an SKM-1 mouse xenograft model of MDS to explore the anti-tumor potential of YSG and its safety, assess its effect on overall survival (OS), and evaluate whether its mechanism is associated with the demethylation of the secreted frizzled related protein 5 (sFRP5) gene and suppressing Wnt/β-catenin pathway. Bisulfite amplicon sequencing was applied to detect the level of methylation of the sFRP5 gene; western blotting, immunofluorescence staining, and real-time Polymerase Chain Reaction were performed to detect DNA methyltransferase 1 (DNMT1), sFRP5, and other Wnt/β-catenin pathway-related mRNA and protein expression.

RESULTS

The results showed that high-dosage YSG exerted an anti-tumor effect similar to that of decitabine, improved OS, and reduced long-term adverse effects in the long term. Mechanically, YSG reduced the expression of DNMT1 methyltransferase, decreased the methylation, and increased the expression of the Wnt/β-catenin pathway antagonist-sFRP5. Furthermore, components of the Wnt/β-catenin pathway, including Wnt3a, β-catenin, c-Myc, and cyclinD1, were down-regulated in response to YSG, suggesting that YSG could treat MDS by demethylating the sFRP5 gene and suppressing the Wnt/β-catenin pathway.

CONCLUSIONS

Our findings demonstrated that YSG could be used alone or in combination with decitabine to improve outcomes in the MDS animal model, providing an alternative solution for treating MDS.

Maintenance therapy in acute myeloid leukemia: advances and controversies

The last decade has seen steadfast progress in drug development in acute myeloid leukemia (AML) which has moved progressively towards genomic-based therapy. With these advances, outcomes in AML have improved but remains far from satisfactory. One approach towards preventing relapse in AML is to use maintenance therapy in patients, after attaining remission. Allogeneic hematopoietic stem cell transplantation (HSCT) is an effective post-remission therapy that has been proven to reduce the risk of relapse. However, in patients who are ineligible for HSCT or have a high risk of relapse, other effective measures to prevent relapse are needed. There is also a need for post-HSCT maintenance to reduce relapse in high-risk subsets. Over the last 3 decades maintenance therapy in AML has evolved from the use of chemotherapeutic agents to more targeted therapies and better modulation of the immune system. Unfortunately, improvements in survival outcomes as a result of using these agents have not been consistently demonstrated in clinical trials. To derive the optimum benefit from maintenance therapy the time points of therapy initiation need to be defined and therapy must be selected precisely with respect to the AML genetics and risk stratification, prior treatment exposure, transplant eligibility, expected toxicity and the patient's clinical profile and desires. The far-reaching goal is to facilitate patients with AML in remission to achieve a normal quality of life while improving remission duration and overall survival. The QUAZAR trial was a welcome step towards a safe maintenance drug that is easy to administer and showed survival benefit but leaves many open issues for discussion. In this review we will discuss these issues, highlighting the development of AML maintenance therapies over the last 3 decades.

Overcoming relapse: prophylactic or pre-emptive use of azacitidine or FLT3 inhibitors after allogeneic transplantation for AML or MDS

Relapse remains the most critical obstacle in treatment by allogeneic hematopoietic stem cell transplantation (HSCT). Non-relapse mortality has improved annually, but relapse mortality remains high. Post-transplant maintenance treatment, such as hypomethylating agents and FMS-like tyrosine kinase 3 (FLT3) inhibitors, has been investigated for decades as a means of preventing disease relapse after HSCT. Other factors besides the relapse tendency of the primary disease that can affect the transition of estimated disease burden in patients undergoing HSCT are disease status at HSCT (non-remission, remission with minimal/measurable residual disease (MRD), and remission without MRD) and conditioning regimen intensity. Optimal selection of patients at high risk for relapse who can tolerate a long duration of therapy is pivotal for successful post-transplant maintenance therapy. In this review, we provide an overview of current progress in research on post-transplant maintenance treatment using azacitidine or FLT3 inhibitors for preventing disease relapse after HSCT for AML or MDS, and discuss the future outlook in this area.

SOHO State of the Art Updates and Next Questions |The Role of Maintenance Therapy in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is an aggressive disease predominantly affecting the elderly population. Although, up to 65% of patients with AML achieve a complete remission with standard induction chemotherapy, the majority of patients will relapse and succumb to the disease. Although maintenance therapy is a component of standard management for various hematological malignancies, such as acute lymphoblastic leukemia (ALL), acute promyelocytic leukemia (APL) or multiple myeloma, past studies investigating the role of maintenance therapy in AML were unable to demonstrate an advantage in overall survival, and therefore, it has not been an established practice in the treatment of AML. For patients, who are not candidates for stem cell transplant, effective AML maintenance therapies are needed in order to reduce the risk of relapse. Over the past decades, many investigators have examined the role of various maintenance strategies in AML; with the intention to prolong remission and overall survival. This review will provide an overview of prior and ongoing approaches and strategies to maintenance therapy for AML.

Activity of decitabine as maintenance therapy in core binding factor acute myeloid leukemia

Background

Posttherapy measurable residual disease (MRD) positivity in core binding factor acute myeloid leukemia (CBF‐AML) is associated with shorter relapse‐free survival (RFS). Elimination of MRD measured via quantitative reverse transcription polymerase chain reaction (qRTPCR) for disease specific transcripts can potentially lead to better outcomes in CBF‐AML.

Methods

We prospectively monitored the MRD using qRTPCR and flow cytometry on bone marrow samples in patients with newly diagnosed CBF‐AML who received decitabine (DAC) maintenance therapy after fludarabine/cytarabine/G‐CSF (FLAG)‐based induction/consolidation regimen. Negative qRTPCR (CMR) was defined as fusion transcript <0.01%.

Results

Thirty‐one patients with CBF‐AML including 14 with t(8;21) and 17 with inv(16) received parenteral DAC as maintenance therapy. Fifteen patients (48.3%) had completed FLAG‐based induction/consolidation but with positive MRD (0.35%, range = 0.01%–0.91%) (Group 1). Sixteen patients (51.7%) could not complete recommended consolidations with FLAG‐based regimen (due to older age or complications) and were switched to DAC maintenance (Group 2). In Group 2, eight patients (50%) had undetectable MRD (Group 2A) (all had qRTPCR ≤ 0.01%) and the other eight patients (50%) had residual fusion product by qRTPCR (0.1%, range = 0.02%–0.36%) (Group 2B) prior to starting DAC. Amongst the 23 patients who had a PCR ≥ 0.01% before maintenance therapy (Groups 1 and 2B), 12 patients (52%) attained a CMR as their best response (responders). The median pre‐DAC qRTPCR amongst responders were 0.03% compared to 0.14% in nonresponders (p = .002). The median estimated molecular RFS amongst responders were 93.9 months. At a median follow‐up of 59.3 months (13.2–106 months) from DAC initiation, 16 patients (51.6%) had to be initiated on a second line of therapy (40%, 25%, and 100% patients, respectively, in Groups1, 2A, and 2B). The median estimated time to new treatment between responders was 112.4 versus 5.8 months in nonresponders (hazard ratio = 0.16, 95% confidence interval = 0.04–0.54); however, there were no difference in overall survival between these groups (p = .37).

Conclusion

DAC is an effective maintenance therapy for CBF‐AML patients with persistent fusion transcript at a low level after FLAG‐based regimen. Attainment of CMR with DAC maintenance can lead to long‐term remission in patients who have persistent MRD positive after FLAG‐based regimen or are unable to receive the full course of consolidation therapy.

Oral azacitidine prolongs survival of patients with AML in remission independent of measurable residual disease status

Measurable residual disease (MRD) in patients with acute myeloid leukemia (AML) in remission after intensive chemotherapy is predictive of early relapse and poor survival. Post-remission maintenance therapy that prolongs MRD negativity or converts MRD positive (MRD+) patients to MRD negative (MRD-) status may delay or prevent relapse and improve overall survival (OS). In the phase 3 QUAZAR AML-001 trial, oral azacitidine (Oral-AZA; formerly CC-486), a hypomethylating agent, significantly prolonged OS and relapse-free survival (RFS) compared with placebo in patients aged ≥55 years with AML in first remission after intensive chemotherapy who were not candidates for hematopoietic stem cell transplantation. In this trial, MRD (≥0.1% leukemic cells in bone marrow) was assessed by multiparameter flow cytometry in serial samples collected at baseline and on day 1 of every 3 cycles. As expected, baseline MRD status was significantly associated with both OS and RFS. Multivariate analyses showed Oral-AZA significantly improved OS and RFS vs. placebo independent of baseline MRD status. Oral-AZA treatment also extended the duration of MRD negativity by 6 months vs. placebo, and resulted in a higher rate of conversion from MRD+ at baseline to MRD- during treatment: 37% vs. 19%, respectively. In the Oral-AZA arm, 24% of MRD responders achieved MRD negativity >6 months after treatment initiation. While presence or absence of MRD was a strong prognostic indicator of OS and RFS, there were added survival benefits with Oral-AZA maintenance therapy compared with placebo, independent of patients' MRD status at baseline. NCT01757535 Clinicaltrials.gov.

Tipifarnib as maintenance therapy did not improve disease-free survival in patients with acute myelogenous leukemia at high risk of relapse: Results of the phase III randomized E2902 trial

PURPOSE

Despite the achievement of complete remission with chemotherapy in patients with acute myeloid leukemia (AML), relapse is common and the majority of patients will die of their disease. Patients who achieve a remission after refractory or relapsed disease as well as elderly patients have a very high rate of relapse even if they achieve a complete remission. A phase 3 randomized ECOG-ACRIN-led intergroup study was conducted to determine whether post-remission therapy with the farnesyl transferase inhibitor, tipifarnib (R115777), improved the disease-free survival (DFS) of adult patients with AML in complete remission (CR), at high risk for relapse.

PATIENTS AND METHODS

Adult patients with AML in remission after salvage therapy and/or over age 60 in first remission were enrolled in this study. They were randomly assigned to treatment with tipifarnib or observation (control). The primary objective was to compare the disease-free survival (DFS) between the two arms based on intention to treat, which includes all randomized patients.

RESULTS

One hundred and forty-four patients were enrolled on the study. Median DFS was 8.9 vs 5.3 months, for tipifarnib vs observation (one-sided p = 0.026) and did not cross the pre-specified boundary to call the study positive. For the 134 eligible patients, median DFS was 10.8 vs 5.3 months for those randomized to tipifarnib vs observation (one-sided p = 0.008). Moreover in an ad hoc evaluation of all women (n = 71) median DFS was 12.1 vs 3.9 months for tipifarnib vs observation (one-sided p = 0.0004) while median OS was 26.5 vs 8.4 months respectively (one-sided p = 0.001).

CONCLUSION

This study was not able to demonstrate a benefit to tipifarnib as maintenance therapy in patients with AML in remission. While subsets of patients may indeed benefit, additional studies would be needed to elucidate that benefit which is unlikely given that other seemingly better options have since become available.

Oral Azacitidine (CC-486) for the Treatment of Myeloid Malignancies

Epigenetic dysregulation leads to aberrant DNA hypermethylation and is common in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). A large number of clinical trials in AML, MDS, and other hematologic malignancies have assessed hypomethylating agents (HMAs), used alone or in combination with other drugs, in the frontline, maintenance, relapsed/refractory, and peritransplant settings. Effective maintenance therapy has long been a goal for patients with AML in remission. Previous large, randomized clinical trials of maintenance with HMAs or other agents had not shown meaningful improvement in overall survival. Oral azacitidine (Oral-AZA [CC-486]) is approved in the United States, Canada, and European Union for treatment of adult patients with AML in first complete remission (CR) or CR with incomplete blood count recovery (CRi) following intensive induction chemotherapy who are ineligible for hematopoietic cell transplant. Regulatory approvals of Oral-AZA were based on outcomes from the randomized, phase III QUAZAR AML-001 trial, which showed a median overall survival advantage of 9.9 months with Oral-AZA versus placebo. Oral-AZA allows convenient extended AZA dosing for 14 days per 28-day treatment cycle, which is not feasible with injectable AZA. Focusing on AML and MDS, this report reviews the rationale for the use of orally bioavailable AZA and its potential use in all-oral combination therapy regimens; the unique pharmacokinetic and pharmacodynamic profile of Oral-AZA compared with injectable AZA; the clinical safety and efficacy of Oral-AZA maintenance therapy in patients with AML in first remission and for treatment of patients with active MDS; and ongoing Oral-AZA clinical trials.

Maintenance therapies in acute myeloid leukemia: the renaissance of an old therapeutic concept

PURPOSE OF REVIEW

Disease relapse remains the major cause of death in patients with acute myeloid leukemia (AML) and is driven by the persistence of leukemic cells following induction chemotherapy or allogeneic hematopoietic cell transplant (allo-HCT). Maintenance therapies to extend the duration of remission and to improve survival have been proposed for several years with mixed results but have experienced a renaissance recently.

RECENT FINDINGS

The oral hypomethylating agent CC-486 has been the first agent to show an overall survival (OS) benefit compared with observation in AML patients in remission following intensive chemotherapy who are not proceeding to allo-HCT. In the realm of postallo-HCT maintenance therapy, the FLT3 inhibitor sorafenib has yielded superior results in terms of OS and relapse-free survival in randomized trials compared with observation. Several open questions remain regarding patient selection, timing, duration and safety of maintenance therapies. Various targeted agents are currently tested in clinical trials and could potentially enable an even more individualized therapeutic approach.

SUMMARY

Maintenance therapies following intensive chemotherapy or allo-HCT offer a new therapeutic paradigm for an increasing number of AML patients and have been shown to result in an OS benefit in selected patients.

AML and the art of remission maintenance

Relapse in acute myeloid leukemia (AML) is common, especially in older patients, and there is currently no standard of care maintenance therapy for those who achieve complete remission. Finding effective, tolerable maintenance therapy to prolong remission has been a goal for decades, but early clinical trials testing a variety of agents demonstrated disappointing results with no overall survival benefit. CC-486, an oral hypomethylating agent, was recently approved in the United States for maintenance treatment in patients with AML in first remission following chemotherapy. A number of ongoing studies are assessing various therapeutics in the maintenance setting, including other hypomethylating agents, targeted small-molecule inhibitors, monoclonal antibodies, and immunomodulators. New strategies are needed to identify patients most likely to benefit from maintenance therapy, including those for whom a preemptive approach reliant on monitoring of measurable residual disease would be advantageous.

Maintenance therapy for acute myeloid leukemia: sustaining the pursuit for sustained remission

PURPOSE OF REVIEW

Maintenance therapy for acute myeloid leukemia (AML) has been studied for decades with mixed results. However, the application of modern agents has renewed interest and the recent data from randomized trials has provided evidence for the use of maintenance therapy in certain populations of AML patients.

RECENT FINDINGS

Unselected patients are unlikely to benefit from maintenance therapy as has been previously and consistently demonstrated. The increasing availability of newer and targeted agents like oral hypomethylating agents, protein modifiers, as well as FLT3, IDH1/2 BCL-2 and immune checkpoint inhibitors have restoked interest in maintenance therapy for which randomized, placebo-controlled trials have recently demonstrated benefits, including in the post-transplant setting. Patients with high-risk disease, suboptimal consolidation or remission associated with measurable residual disease (MRD) appear to be beneficiaries of this strategy. The influence of MRD status and the platform by which it is measured are important factors in the current understanding of when maintenance therapy works and how future studies should be designed.

SUMMARY

The recent positive findings in support of maintenance therapy for certain AML patient populations are practice changing and bolster the need for properly designed, randomized studies using unified and standardized MRD techniques.

Maintenance Therapy in AML

Recent advances in therapeutics coupled with steady improvements in supportive care for patients with acute myeloid leukemia (AML) have led to improved outcomes. Despite these advances, even in patients that achieve a complete remission with initial therapy high rates of relapse remain a clinical dilemma. For decades, investigators have attempted strategies of maintenance therapy to prolong both remission duration and overall survival in patients with AML. These approaches have included cytotoxic chemotherapy, immunotherapy, hypomethylating agents, and targeted small molecule therapy. Overall, the evidence in favor of maintenance therapy is limited. Recent strategies, especially with hypomethylating agents have begun to show promise as maintenance therapy in improving clinical outcomes. Ongoing and future studies will continue to elucidate the true role for maintenance therapy options in patients with AML. In this review we summarize prior and ongoing maintenance therapy approaches in AML and highlight some of the most promising strategies.

Phase 2 study of lenalidomide maintenance for patients with high-risk acute myeloid leukemia in remission

BACKGROUND

New drug combinations have led to significant improvements in remission rates for patients with acute myeloid leukemia (AML). However, many patients with high-risk AML who respond to their initial treatment and are not candidates for allogeneic stem cell transplantation (ASCT) will eventually relapse with poor outcomes.

METHODS

In this phase 2 trial, the efficacy of lenalidomide maintenance was evaluated in patients with high-risk AML who had achieved their first or second remission after induction chemotherapy and at least 1 consolidation cycle and who were not candidates for immediate ASCT. Lenalidomide was given orally at 10 to 20 mg daily on days 1 to 28 of a 28-day cycle for up to 24 cycles.

RESULTS

A total of 28 patients were enrolled in this study with a median age of 61 years (range, 24-87 years). The median number of cycles was 8 (range, 1-24 cycles). Ten patients (36%) completed 24 months of maintenance treatment. With a median follow-up of 22.5 months (range, 2.6-55 months), 12 patients (43%) relapsed after a median of 3 months (range, 0.7-23 months). The median duration of remission for all patients was 18.7 months (range, 0.7-55.1 months). The 2-year overall survival and relapse-free survival rates from the time of enrollment were 63% and 50%, respectively. Overall, lenalidomide was well tolerated; serious adverse events of grade 3 or 4, including rash (n = 5), thrombocytopenia (n = 4), neutropenia (n = 4), and fatigue (n = 2), were observed in 13 patients (46%).

CONCLUSIONS

Lenalidomide is a safe and feasible maintenance strategy in patients with high-risk AML who are not candidates for ASCT, and it has beneficial effects for patients with negative measurable residual disease.

Indirect comparison of azacitidine and decitabine for the therapy of elderly patients with acute myeloid leukemia: a systematic review and network meta-analysis

Background

The DNA hypomethylating agents (HMAs) decitabine and azacitidine have been widely used in the management of elderly patients with acute myeloid leukemia (AML). However, no direct clinical trials have been carried out to compare the two agents. A systematic review and network meta-analysis were performed to indirectly compare the efficacy and safety of decitabine and azacitidine in elderly AML patients.

Methods

We systematically searched PubMed, Medline, Web of Science, Embase and Cochrane Library through May 14, 2019. Randomized controlled trials on elderly AML patients comparing the efficacy and safety between decitabine and azacitidine, or comparing one of HMAs to standard supportive care or placebo were selected. The major outcomes of interest were performed with methods of adjusted indirect comparison and the fixed effect model.

Results

Only three RCTs including a total number of 1086 patients were identified. Direct comparisons showed that azacitidine significantly reduced mortality (RR = 0.90, 95% CI 0.83–0.97) while decitabine was not significantly associated with lower mortality (RR = 0.97, 95% CI 0.92–1.02) compared to the conventional care regimen (CCR). In addition, for the indirect method, azacitidine significantly reduced mortality compared to decitabine (RR = 0.83 95% CI 0.77–0.90) and was more likely to improve complete response (CR) (RR = 1.66, 95% CI 1.17–2.35, low-certainty evidence). No statistical significance was found for the other studied outcomes.

Conclusions

Compared to CCR, decitabine and azacitidine can promote studied outcomes in elderly AML patients. Indirect evidence with low certainty was used to compare these two agents. The superiority of either agent cannot be confirmed, and head-to-head clinical trials are still required.

Maintenance therapy in AML: The past, the present and the future

Curative treatment in acute myeloid leukemia (AML) depends on successful induction therapy to achieve a complete remission (CR), and subsequent post-remission therapy to prevent relapse. High relapse rates after consolidation therapy and after allogeneic stem cell transplant contribute to suboptimal outcomes in AML patients, and continue to represent a difficult challenge. Effective maintenance therapy could play an important role in prolonging the remission interval in the post-consolidation setting, especially in high risk AML patients. Maintenance treatment approaches based on conventional chemotherapy, immunotherapy, hypomethylating agents, and targeted small molecules have been explored in this setting, but no data so far have been convincing enough to establish this approach as the standard of care. However, ongoing and future studies including novel targeted therapies may demonstrate promising efficacy that could facilitate incorporation of maintenance therapy into clinical practice. In this review we summarize previous and ongoing approaches of maintenance therapy in AML and discuss the most promising strategies.

How close are we to incorporating measurable residual disease into clinical practice for acute myeloid leukemia?

Assessment of measurable residual disease, also called "minimal residual disease," in patients with acute myeloid leukemia in morphological remission provides powerful prognostic information and complements pretreatment factors such as cytogenetics and genomic alterations. Based on data that low levels of persistent or recurrent residual leukemia are consistently associated with an increased risk of relapse and worse long-term outcomes, its routine assessment has been recommended by some experts and consensus guidelines. In addition to providing important prognostic information, the detection of measurable residual disease may also theoretically help to determine the optimal post-remission strategy for an individual patient. However, the full therapeutic implications of measurable residual disease are uncertain and thus controversy exists as to whether it should be routinely incorporated into clinical practice. While some evidence supports the use of allogeneic stem cell transplantation or hypomethylating agents for some subgroups of patients in morphological remission but with detectable residual leukemia, the appropriate use of this information in making clinical decisions remains largely speculative at present. To resolve this pressing clinical issue, several ongoing studies are evaluating measurable residual disease-directed treatments in acute myeloid leukemia and may lead to new, effective strategies for patients in these circumstances. This review examines the common technologies used in clinical practice and in the research setting to detect residual leukemia, the major clinical studies establishing the prognostic impact of measurable residual disease in acute myeloid leukemia, and the potential ways, both now and in the future, that such testing may rationally guide therapeutic decision-making.

Clinical update on hypomethylating agents

Hypomethylating agents (HMAs), azacitidine and decitabine, are standards of care in higher-risk myelodysplastic syndromes and in acute myeloid leukemia patients ineligible for intensive therapy. Over the last 10 years, research efforts have sought to better understand their mechanism of action, both at the molecular and cellular level. These efforts have yet to robustly identify biomarkers for these agents. The clinical activity of HMAs in myeloid neoplasms has been firmly established now but still remains of limited magnitude. Besides optimized use at different stages of the disease, most of the expected clinical progress with HMAs will come from the development of second-generation compounds orally available and/or with improved pharmacokinetics, and from the search, so far mostly empirical, of HMA-based synergistic drug combinations.

Azacitidine maintenance after intensive chemotherapy improves DFS in older AML patients

The prevention of relapse is the major therapeutic challenge in older patients with acute myeloid leukemia (AML) who have obtained a complete remission (CR) on intensive chemotherapy. In this randomized phase 3 study (HOVON97) in older patients (≥60 years) with AML or myelodysplastic syndrome with refractory anemia with excess of blasts, in CR/CR with incomplete hematologic recovery (CRi) after at least 2 cycles of intensive chemotherapy, we assessed the value of azacitidine as postremission therapy with respect to disease-free survival (DFS; primary end point) and overall survival (OS; secondary end point). In total, 116 eligible patients were randomly (1:1) assigned to either observation (N = 60) or azacitidine maintenance (N = 56; 50 mg/m2, subcutaneously, days 1-5, every 4 weeks) until relapse, for a maximum of 12 cycles. Fifty-five patients received at least 1 cycle of azacitidine, 46 at least 4 cycles, and 35 at least 12 cycles. The maintenance treatment with azacitidine was feasible. DFS was significantly better for the azacitidine treatment group (logrank; P = .04), as well as after adjustment for poor-risk cytogenetic abnormalities at diagnosis and platelet count at randomization (as surrogate for CR vs CRi; Cox regression; hazard ratio, 0.62; 95% confidence interval, 0.41-0.95; P = .026). The 12-month DFS was estimated at 64% for the azacitidine group and 42% for the control group. OS did not differ between treatment groups, with and without censoring for allogeneic hematopoietic cell transplantation. Rescue treatment was used more often in the observation group (n = 32) than in the azacitidine maintenance group (n = 9). We conclude that azacitidine maintenance after CR/CRi after intensive chemotherapy is feasible and significantly improves DFS. The study is registered with The Netherlands Trial Registry (NTR1810) and EudraCT (2008-001290-15).

Is it time to routinely incorporate MRD into practice?

Interest in detecting minimal/measurable residual disease (MRD) in acute myeloid leukemia (AML) has been increasing, but numerous issues need to be addressed if MRD assessment is to be routinely incorporated into practice. Assays, their reliability, standardization, and availability all must be considered, and a strategy developed to eradicate residual leukemia. This paper reviews some issues surrounding the routine incorporation of MRD assessment into practice.

Incidence and risk of hematologic toxicities with hypomethylating agents in the treatment of myelodysplastic syndromes and acute myeloid leukopenia: A systematic review and meta-analysis

BACKGROUND

Hypomethylating agents (HMAs) are believed to have reliable efficacy in treating myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Meanwhile, the adverse events of HMAs have become an increasing concern. There is, however, no systematic meta-analysis available to evaluate overall hematologic toxicities for HMAs. In this meta-analysis, we aim to determine the risk of hematologic toxicities in patients treated with HMAs.

METHODS

Relevant studies were identified from PubMed, Embase, Cochrane Library, and the Clinical Trials. gov databases incepted to February 2018. All phase II and III trials meeting the inclusion criteria included adequate safety data. We calculated the relative risk (RR) of high-grade hematologic toxicities (HTEs) with corresponding 95% CI using Review Manager. The incidences of HTEs were also evaluated by R. Heterogeneity was calculated and reported mainly via I analyses.

RESULTS

A total of 2337 MDS or AML patients from 14 studies were identified in this meta-analysis. The overall incidences of high-grade hematologic toxicities in patients who received HMAs were: 27% of the patients with anemia, 45% with neutropenia, 38% with thrombocytopenia, and 25% with febrile neutropenia, respectively. There was a significantly increased RR of neutropenia and thrombocytopenia using HMAs, in comparison with conventional care regimens (CCR) based on the drug type (decitabine vs azacitidine).

CONCLUSIONS

We conclude that the use of HMAs are associated with an increased risk of neutropenia and thrombocytopenia in MDS or AML patients, and our results also demonstrate that HMAs exposure does not significantly increase the risk of high-grade anemia, leukopenia, or febrile neutropenia compared with CCR.

Acute myeloid leukemia in the elderly: therapeutic options and choice

Acute myeloid leukemia (AML) therapies are rapidly evolving with novel targeted therapies showing high-level responses in a notoriously difficult to treat group of patients - the elderly and unfit. This review will examine the outcomes of older AML patients (>60 years old) with conventional induction strategies, and published literature on risks of pursuit of induction. Low-intensity combination therapy response rates appear to be approaching that of induction regimens, and with lower toxicity, low-intensity therapy likely represents the future standard approach in this age group. Lastly, allogeneic transplant appears to have a role in increasing durable remissions regardless of age and should be considered in patients with limited comorbidities.

Minimal residual disease eradication with epigenetic therapy in core binding factor acute myeloid leukemia

Recurrent translocations, t(8;21) or inv(16), in core binding factor acute myeloid leukemia (CBF-AML) are amenable to monitoring for minimal residual disease (MRD) with reverse transcriptase polymerase chain reaction (RTPCR). Despite a favorable prognosis, disease relapse remains the single cause of treatment failure in CBF-AML. Fusion products of these translocations recruit epigenetic silencing complexes resulting in hematopoietic maturation arrest. We hypothesized that maintenance therapy with hypomethylating agents (HMA), including decitabine (DAC) and azacitidine (AZA) after induction/consolidation, can be used for MRD elimination to ultimately prolong relapse free survival. Real-time quantitative (RTPCR) trends were reviewed in 23 patients (median age 53 years) with CBF-AML that received HMA therapy following induction/consolidation with fludarabine, cytarabine, and G-CSF (FLAG) with low dose gemtuzumab or idarubicin (NCT00801489). Of the 23 patients evaluated, 17 had a detectable RTPCR at HMA initiation. Five patients had progressive disease and a notable increase in RTPCR values over 1-2 cycles of HMA therapy. Twelve patients did not fail HMA and had a median RTPCR at HMA initiation of 0.06 (range, 0.01-0.91). Unlike the HMA failure subset, 11 of these patients had a reduction in RTPCR after the first or second cycle of HMA. Our data suggests that CBF-AML patients with low levels of RTPCR (between 0.01 and 0.05) at the conclusion of induction/consolidation chemotherapy benefit most from maintenance HMA, particularly those that have a reduction in the RTPCR within the first two cycles of HMA therapy.

Antileukemia Efficacy and Mechanisms of Action of SL-101, a Novel Anti-CD123 Antibody Conjugate, in Acute Myeloid Leukemia

Purpose: The persistence of leukemia stem cells (LSC)-containing cells after induction therapy may contribute to minimal residual disease (MRD) and relapse in acute myeloid leukemia (AML). We investigated the clinical relevance of CD34⁺CD123⁺ LSC-containing cells and antileukemia potency of a novel antibody conjugate SL-101 in targeting CD123⁺ LSCs.Experimental Methods and Results: In a retrospective study on 86 newly diagnosed AML patients, we demonstrated that a higher proportion of CD34⁺CD123⁺ LSC-containing cells in remission was associated with persistent MRD and predicted shorter relapse-free survival in patients with poor-risk cytogenetics. Using flow cytometry, we explored the potential benefit of therapeutic targeting of CD34⁺CD38^-CD123⁺ cells by SL-101, a novel antibody conjugate comprising an anti-CD123 single-chain Fv fused to Pseudomonas exotoxin A The antileukemia potency of SL-101 was determined by the expression levels of CD123 antigen in a panel of AML cell lines. Colony-forming assay established that SL-101 strongly and selectively suppressed the function of leukemic progenitors while sparing normal counterparts. The internalization, protein synthesis inhibition, and flow cytometry assays revealed the mechanisms underlying the cytotoxic activities of SL-101 involved rapid and efficient internalization of antibody, sustained inhibition of protein synthesis, induction of apoptosis, and blockade of IL3-induced p-STAT5 and p-AKT signaling pathways. In a patient-derived xenograft model using NSG mice, the repopulating capacity of LSCs pretreated with SL-101 in vitro was significantly impaired.Conclusions: Our data define the mechanisms by which SL-101 targets AML and warrant further investigation of the clinical application of SL-101 and other CD123-targeting strategies in AML. Clin Cancer Res; 23(13); 3385-95. ©2017 AACR.

Dynamic changes in the clonal structure of MDS and AML in response to epigenetic therapy

Traditional response criteria in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) are based on bone marrow morphology and may not accurately reflect clonal tumor burden in patients treated with non-cytotoxic chemotherapy. We used next-generation sequencing of serial bone marrow samples to monitor MDS and AML tumor burden during treatment with epigenetic therapy (decitabine and panobinostat). Serial bone marrow samples (and skin as a source of normal DNA) from 25 MDS and AML patients were sequenced (exome or 285 gene panel). We observed that responders, including those in complete remission (CR), can have persistent measurable tumor burden (that is, mutations) for at least 1 year without disease progression. Using an ultrasensitive sequencing approach, we detected extremely rare mutations (equivalent to 1 heterozygous mutant cell in 2000 non-mutant cells) months to years before their expansion at disease relapse. While patients can live with persistent clonal hematopoiesis in a CR or stable disease, ultimately we find evidence that expansion of a rare subclone occurs at relapse or progression. Here we demonstrate that sequencing of serial samples provides an alternative measure of tumor burden in MDS or AML patients and augments traditional response criteria that rely on bone marrow blast percentage.

The hypomethylating agent decitabine prior to chemotherapy improves the therapy efficacy in refractory/relapsed acute myeloid leukemia patients

In this study, we investigated the effect of pre-treatment with demethylating agent decitabine on susceptibility to chemotherapeutic drugs in HL60/ADR, Kasumi-1 and primary AML cells. Cytotoxic effect was increased by decitabine through activation of p53 and inhibition of c-Myc, Survivin and Bcl-2. We demonstrated in clinic that combination of decitabine and HAA consisting of harringtonine, aclarubicin and cytarabine was effective and safe to treat patients with refractory, relapsed or high-risk AML. Decitabine prior to HAA regimen improved the first induction complete response rate, and significantly prolonged overall survival and disease-free survival in these patients compared with HAA alone. These findings support clinic protocols based on decitabine prior to chemotherapy to overcome resistance and improve therapeutic efficacy in AML patients.

Maintenance therapy with decitabine in younger adults with acute myeloid leukemia in first remission: a phase 2 Cancer and Leukemia Group B Study (CALGB 10503)

In this prospective phase 2 clinical trial conducted by Cancer and Leukemia Group B (CALGB, now the Alliance), we studied decitabine as maintenance therapy for younger adults with acute myeloid leukemia (AML) who remained in first complete remission (CR1) following intensive induction and consolidation. Given that decitabine is clinically active in AML and with hypomethylating activity distinct from cytotoxic chemotherapy, we hypothesized that one year of maintenance therapy would improve disease-free survival (DFS) for AML patients <60 years who did not receive allogeneic stem cell transplantation (alloHCT) in CR1. After blood count recovery from final consolidation, patients received decitabine at 20mg/m² IV daily for 4–5 days, every 6 weeks for 8 cycles. One-hundred-thirty-four patients received decitabine, 85 (63%) had favorable risk AML. The median number of cycles received was 7 (range, 1–8), and the primary reason for discontinuation was relapse. DFS at 1-year and 3-years was 79% and 54%, respectively. These results are similar to the outcomes in the historical control comprised of similar patients treated on recent CALGB trials. Thus, maintenance with decitabine provided no benefit overall. Standard use of decitabine maintenance in younger AML patients in CR1 is not warranted. This trial was registered at www.clinicaltrials.gov as NCT00416598.

Acute myeloid leukemia: 2016 Update on risk-stratification and management

Evidence suggest that even patients aged 70 or above benefit from specific AML therapy. The fundamental decision in AML then becomes whether to recommend standard or investigational treatment. This decision must rest on the likely outcome of standard treatment. Hence we review factors that predict treatment related mortality and resistance to therapy, the latter the principal cause of failure even in patients aged 70 or above. We emphasize the limitations of prediction of resistance based only on pre- treatment factors and stress the need to incorporate post-treatment factors, for example indicators of minimal residual disease. We review various newer therapeutic options and considerations that underlie the decision to recommend allogeneic hematopoietic cell transplant. Am. J. Hematol. 91:825-846, 2016. © 2016 Wiley Periodicals, Inc.

Are we curing more older adults with acute myeloid leukemia with allogeneic transplantation in CR1?

PURPOSE OF REVIEW

Despite the fact that acute myeloid leukemia (AML) is most common in older adults aged at least 60 years, curative therapy remains elusive in this population. Here we examine the data for predicting which patients are candidates for 'curative therapy', available therapeutic options, and the utilization of reduced intensity allogeneic stem cell transplantation in first remission.

RECENT FINDINGS

Incorporation of geriatric assessment tools to assess patient frailty, in addition to evaluation of comorbid conditions, improves patient selection for intense therapy. The majority of patients eligible for and treated with induction chemotherapy achieve complete remission, and overall survival in the older AML population is superior after allogeneic stem cell transplant. However, population-based studies continue to demonstrate the undertreatment or lack of treatment of older AML patients.

SUMMARY

New patient assessment tools, ability to offer more successful outcomes after induction chemotherapy, and improved survival after allogeneic transplantation has not yet translated to increased 'curative' treatment on a population level of older AML patients. It is critical that the tools and therapies available be put into practice while older patient enrollment in well designed therapeutic clinical trials which include the option of allogeneic transplantation is increased.

Design of the randomized, Phase III, QUAZAR AML Maintenance trial of CC-486 (oral azacitidine) maintenance therapy in acute myeloid leukemia

Older patients with acute myeloid leukemia (AML) have worse rates of complete remission and shorter overall survival than younger patients. The epigenetic modifier CC-486 is an oral formulation of azacitidine with promising clinical activity in patients with AML in Phase I studies. The Phase III, randomized, double-blind, placebo-controlled QUAZAR AML Maintenance trial (CC-486-AML-001) examines CC-486 maintenance therapy (300 mg/day for 14 days of 28-day treatment cycles) for patients aged ≥55 years with AML in first complete remission. The primary end point is overall survival. Secondary end points include relapse-free survival, safety, health-related quality of life and healthcare resource utilization. This trial will investigate whether CC-486 maintenance can prolong remission and improve survival for older patients with AML.

Epigenetic synergy between decitabine and platinum derivatives

Background

Aberrant epigenetic silencing of tumor suppressor genes has been recognized as a driving force in cancer. Epigenetic drugs such as the DNA methylation inhibitor decitabine reactivate genes and are effective in myeloid leukemia, but resistance often develops and efficacy in solid tumors is limited. To improve their clinical efficacy, we searched among approved anti-cancer drugs for an epigenetic synergistic combination with decitabine.

Results

We used the YB5 cell line, a clonal derivative of the SW48 colon cancer cell line that contains a single copy of a hypermethylated cytomegalovirus (CMV) promoter driving green fluorescent protein (GFP) to screen for drug-induced gene reactivation and synergy with decitabine. None of the 16 anti-cancer drugs tested had effects on their own. However, in combination with decitabine, platinum compounds showed striking synergy in activating GFP. This was dose dependent, observed both in concurrent and sequential combinations, and also seen with other alkylating agents. Clinically achievable concentrations of carboplatin at (25 μM) and decitabine reactivated GFP in 28 % of the YB5 cells as compared to 15 % with decitabine alone. Epigenetic synergy was also seen at endogenously hypermethylated tumor suppressor genes such as MLH1 and PDLIM4. Genome-wide studies showed that reactivation of hypermethylated genes by the combination was significantly better than that induced by decitabine alone or carboplatin alone. Platinum compounds did not enhance decitabine-induced hypomethylation. Rather, we found significantly inhibited HP1α expression by carboplatin and the combination. This was accompanied by increased histone H3 lysine 4 (H3K4) trimethylation and histone H3 lysine 9 (H3K9) acetylation at reactivated genes (P < 0.0001) and reduced occupancy by methyl-binding proteins including MeCP2 and methyl-CpG-binding domain protein 2 (MBD2) (P < 0.0001).

Conclusions

Our results suggest that the combination of decitabine with platinum analogs shows epigenetic synergy that might be exploited in the treatment of different cancers.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-015-0131-z) contains supplementary material, which is available to authorized users.

A multicenter, phase II study of maintenance azacitidine in older patients with acute myeloid leukemia in complete remission after induction chemotherapy

Older patients with acute myeloid leukemia (AML) have poor outcomes, with median durations of complete remission lasting less than 1 year. Increased toxicity in older patients limits the delivery of standard consolidation therapies, such as allogeneic stem cell transplant or high-dose cytarabine. Azacitidine, a nucleoside analog/DNA methyltransferase inhibitor, has demonstrated significant activity and favorable tolerability in patients unable to tolerate intensive induction chemotherapy; however, the role of azacitidine in the maintenance setting has not been fully evaluated. We undertook a pilot study of low-dose subcutaneous azacitidine [50 mg/(m(2) day)] for 5 days every 4 weeks) in AML patients ≥60 years of age in first remission following standard induction therapy. The primary objective was to determine the 1-year disease-free survival (DFS); secondary objectives were to determine safety and tolerability. We enrolled 24 patients (median age 68, range 62-81 years), the majority of whom received anthracycline-cytarabine induction regimens. From the time of first complete remission, the estimated 1-year DFS was 50% and the median overall survival was 20.4 months. Thrombocytopenia and neutropenia were the most common grade 3/4 toxicities (50 and 58%, respectively). In our study population, maintenance therapy with subcutaneous azacitidine was safe and well tolerated.

Clinical Results of Hypomethylating Agents in AML Treatment

Epigenetic changes play an important role in the development of acute myeloid leukemia (AML). Unlike gene mutations, epigenetic changes are potentially reversible, which makes them attractive for therapeutic intervention. Agents that affect epigenetics are the DNA methyltransferase inhibitors, azacitidine and decitabine. Because of their relatively mild side effects, azacitidine and decitabine are particularly feasible for the treatment of older patients and patients with co-morbidities. Both drugs have remarkable activity against AML blasts with unfavorable cytogenetic characteristics. Recent phase 3 trials have shown the superiority of azacitidine and decitabine compared with conventional care for older AML patients (not eligible for intensive treatment). Results of treatment with modifications of the standard azacitidine (seven days 75 mg/m(2) SC; every four weeks) and decitabine (five days 20 mg/m(2) IV; every four weeks) schedules have been reported. Particularly, the results of the 10-day decitabine schedule are promising, revealing complete remission (CR) rates around 45% (CR + CRi (i.e., CR with incomplete blood count recovery) around 64%) almost comparable with intensive chemotherapy. Application of hypomethylating agents to control AML at the cost of minimal toxicity is a very promising strategy to "bridge" older patients with co-morbidities to the potential curative treatment of allogeneic hematopoietic cell transplantation. In this article, we discuss the role of DNA methyltransferase inhibitors in AML.

Epigenetic targeting and personalized approaches for AML

Acute myeloid leukemia (AML) is a genetically heterogeneous clonal hematopoietic stem cell disorder and the majority of patients with AML die from their disease. The treatment paradigms for AML were developed decades ago and, although there have been improvements in the outcomes of selected younger patients and those with specific cytogenetic and molecular genetic characteristics, the overall survival for older patients remains dismal. Over the last few years, next-generation sequencing technologies have identified recurrent mutations in genes encoding proteins involved in the epigenetic regulation of transcription in most patients with AML. This discovery has led to new insights into the role of the epigenome in AML and opens the possibility of epigenetically targeted therapies. This chapter describes how epigenetic dysregulation plays a role in AML and highlights current and future treatment strategies that attempt to exploit epigenetic targets.

Acute myeloid leukemia: 2014 update on risk-stratification and management

OVERVIEW

Evidence suggests that even patients aged 70 or above benefit from specific AML therapy. The fundamental decision in AML then becomes whether to recommend standard or investigational treatment. This decision must rest on the likely outcome of standard treatment. Hence we review factors that predict treatment related mortality and resistance to therapy, the latter the principal cause of failure even in patients aged 70 or above. We emphasize the limitations of prediction of resistance based only on pre-treatment factors and stress the need to incorporate post-treatment factors, for example indicators of minimal residual disease. We review various newer therapeutic options and considerations that underlie the decision to recommend allogeneic hematopoietic cell transplant.

Phase I study of oral clofarabine consolidation in adults aged 60 and older with acute myeloid leukemia

Clofarabine has shown activity and tolerability in older patients with acute myeloid leukemia (AML). We investigated the safety and tolerability of an oral formulation of clofarabine for consolidation therapy of patients aged 60 and older with AML. In this phase I study, twenty-two patients older than 60 years with AML in first complete remission were treated once daily with oral clofarabine for 14 or 21 days of a 28-day cycle, for up to five cycles. Dose escalation from 1 mg to 6 mg daily using a 3 + 3 design was used to determine dose-limiting toxicities (DLT), the maximum tolerated dose (MTD), and tolerability of oral clofarabine. No DLTs or Grade 3-4 nonhematologic toxicities were observed. The primary toxicities were hematologic, including uncomplicated grade 3-4 neutropenia (50%) and thrombocytopenia (50%). Given that myelosuppression necessitating dose delays/reductions was observed more commonly at higher doses, the recommended phase II dose is 2 mg daily for 21 of 28 days. At doses equal to or greater than 2 mg, the median relapse-free survival was 28.35 months. Oral clofarabine was well-tolerated with encouraging activity in patients older than 60 years. Further investigation of oral clofarabine as a consolidation and/or maintenance therapy in AML for older individuals is warranted. (ClinicalTrials.gov:NCT00727766).

Survival improvement of poor-prognosis AML/MDS patients by maintenance treatment with low-dose chemotherapy and differentiating agents

We evaluated a maintenance, post-remission treatment with low-dose chemotherapy plus differentiating agents on poor-prognosis acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) patients ineligible to allografting. Patients had either age over 60 and/or secondary AML, therapy-related AML, previous relapse, high-risk MDS. Forty-five patients received the maintenance therapy based on two alternated schedules: (a) 6-thioguanine + 13-cis retinoic acid + dihydroxylated vitamin D3 and (b) low-dose cytarabine + 6-mercaptopurine + all-trans retinoic acid + dihydroxylated vitamin D3. We compared their outcome, at a median follow-up of 52 months, to that of a matched population of 49 patients who stopped treatments after consolidation. Maintenance group had a lower relapse incidence (70.3 vs. 86.4 % at 5 years p = 0.007) and a longer disease-free survival (median 21.2 vs. 8.7 months, p = 0.017). The relapse reduction improved overall survival: median 40.4 months (35.9 % at 5 years) for maintenance group vs. 15.8 (14.2 % at 5 years) for controls (p = 0.005). At multivariate Cox analysis, both cytogenetic and maintenance therapies resulted independent outcome predictors for overall survival. Maintenance treatment also reduced minimal residual disease (detected by WT1 and CBFβ-MYH11) in five of eight evaluable patients. The present results suggest that our strategy of maintenance therapy might improve the outcome of poor-risk AML/MDS patients.

Decitabine: a review of its use in older patients with acute myeloid leukaemia

Decitabine (Dacogen(®)) is a deoxynucleoside analogue of cytidine that selectively inhibits DNA methyltransferases. Decitabine administered at a dose of 20 mg/m(2) by a 1-h intravenous infusion for 5 consecutive days of a 4-week cycle has been approved by the European Medicines Agency (EMA) for use in adult patients aged ≥65 years with de novo or secondary acute myeloid leukaemia (AML) who are not candidates for standard induction therapy. Decitabine, compared with treatment choice (cytarabine or supportive care), did not result in a statistically significant improvement in median overall survival (OS) in older patients with AML at the pre-specified primary endpoint of a pivotal phase III trial. However, the improvement in OS was considered by the EMA to be clinically meaningful. After a further year of follow-up, an analysis of the mature survival data demonstrated a statistical significance in median OS in favour of decitabine over treatment choice. Complete remission (CR) rates in the phase III trial were significantly improved with decitabine versus treatment choice. The overall safety profile of decitabine in older patients with AML was generally similar to that of cytarabine, with pyrexia, thrombocytopenia and anaemia being the most commonly reported adverse events. In conclusion, low-dose decitabine may be considered as an effective and generally well tolerated alternative treatment to cytarabine or supportive care in older patients with AML who are not candidates for standard induction therapy.

Update on optimal management of acute myeloid leukemia

Acute myeloid leukemia (AML) represents a malignant accumulation of immature myeloid cells in the marrow, presenting with impaired hematopoiesis and its attendant complications, including bleeding, infection, and organ infiltration. Chromosomal abnormalities remain the most powerful predictors of AML prognosis and help to identify a subgroup with favorable prognosis. However, the majority of AML patients who are not in the favorable category succumb to the disease. Therefore, better efforts to identify those patients who may benefit from more aggressive and investigational therapeutic approaches are needed. Newer molecular markers aim at better characterizing the large group of intermediate-risk patients and to identify newer targets for therapy. A group that has seen little improvement over the years is the older AML group, usually defined as age ≥ 60. Efforts to develop less intensive but equally efficacious therapy for this vulnerable population are underway.