Outcomes after induction chemotherapy in patients with acute myeloid leukemia arising from myelodysplastic syndrome

Survival difference between secondary and de novo acute myeloid leukemia by age, antecedent cancer types, and chemotherapy receipt

BACKGROUND

This study compared the survival of persons with secondary acute myeloid leukemia (sAML) to those with de novo AML (dnAML) by age at AML diagnosis, chemotherapy receipt, and cancer type preceding sAML diagnosis.

METHODS

Data from Surveillance, Epidemiology, and End Results 17 Registries were used, which included 47,704 individuals diagnosed with AML between 2001 and 2018. Multivariable Cox proportional hazards regression was used to compare AML-specific survival between sAML and dnAML. Trends in 5-year age-standardized relative survival were examined via the Joinpoint survival model.

RESULTS

Overall, individuals with sAML had an 8% higher risk of dying from AML (hazard ratio [HR], 1.08; 95% confidence interval [CI], 1.05-1.11) compared to those with dnAML. Disparities widened with younger age at diagnosis, particularly in those who received chemotherapy for AML (HR, 1.14; 95% CI, 1.10-1.19). In persons aged 20-64 years and who received chemotherapy, HRs were greatest for those with antecedent myelodysplastic syndrome (HR, 2.04; 95% CI, 1.83-2.28), ovarian cancer (HR, 1.91; 95% CI, 1.19-3.08), head and neck cancer (HR, 1.55; 95% CI, 1.02-2.36), leukemia (HR, 1.45; 95% CI, 1.12-1.89), and non-Hodgkin lymphoma (HR, 1.42; 95% CI, 1.20-1.69). Among those aged ≥65 years and who received chemotherapy, HRs were highest for those with antecedent cervical cancer (HR, 2.42; 95% CI, 1.15-5.10) and myelodysplastic syndrome (HR, 1.28; 95% CI, 1.19-1.38). The 5-year relative survival improved 0.3% per year for sAML slower than 0.86% per year for dnAML. Consequently, the survival gap widened from 7.2% (95% CI, 5.4%-9.0%) during the period 2001-2003 to 14.3% (95% CI, 12.8%-15.8%) during the period 2012-2014.

CONCLUSIONS

Significant survival disparities exist between sAML and dnAML on the basis of age at diagnosis, chemotherapy receipt, and antecedent cancer, which highlights opportunities to improve outcomes among those diagnosed with sAML.

Real-world treatment outcomes from a retrospective cohort of patients with acute myeloid leukemia from an urban safety net hospital

INTRODUCTION

While continual advancements in acute myeloid leukemia have augmented response rates and survival, outcomes in clinical trials may not correlate with real-world practice as trials may underrepresent individuals with comorbidities, decreased performance status, and older age. Additionally, clinical trials may underrepresent certain ethnicities, and disparities based on ethnicity, socioeconomic status, and insurance have been demonstrated in acute myeloid leukemia.

METHODS

We performed a retrospective chart review of adult patients with acute myeloid leukemia who were treated at Harbor-UCLA from 2014 to 2022 to examine patient characteristics, management patterns, and outcomes in a safety net hospital setting.

RESULTS

The median age was 56 years old (range 18-84). In regards to risk stratification, 22%, 33%, and 41% had favorable, intermediate, and adverse risk acute myeloid leukemia, respectively. The most common induction regimens included 7 + 3 (55%), azacitidine (10%), azacitidine + venetoclax (7%), and 7 + 3 + midostaurin (7%). The complete remission rate was 51%. Among patients who received intensive induction chemotherapy, 15% underwent re-induction with a second cycle, 51% received consolidation therapy, and 5% received maintenance therapy with a targeted agent. Overall, 12% of patients received allogeneic stem cell transplant. Median overall survival was 12.2 months, and 5-year overall survival was 18%.

CONCLUSIONS

Suboptimal response rates and survival in this population may be related to low rates of re-induction and allogeneic transplant in addition to high rates of adverse cytogenetics, secondary acute myeloid leukemia, and supportive care only. Efforts to increase access to clinical trials, novel therapies, and transplants for diverse and underinsured populations are essential.

Poor post-induction outcomes in patients with acute myeloid leukemia previously treated with hypomethylating agents

Patients with acute myeloid leukemia (AML) who have failed hypomethylating agents (HMA) have a poor prognosis. We examined whether high intensity induction chemotherapy could abrogate negative outcomes in 270 patients with AML or other high-grade myeloid neoplasms. Prior HMA therapy was significantly associated with a lower overall survival (OS) as compared to a reference group of patients with secondary disease without prior HMA therapy (median 7.2 vs 13.1 months). In patients with prior HMA therapy, high intensity induction was associated with a non-significant trend toward longer OS (median 8.2 vs 4.8 months) and decreased rates of treatment failure (39% vs 64%). These results redemonstrate poor outcomes in patients with prior HMA and suggest possible benefit of high intensity induction that should be evaluated in future studies.

Understanding the Continuum between High-Risk Myelodysplastic Syndrome and Acute Myeloid Leukemia

Myelodysplastic syndrome (MDS) is a clonal hematopoietic neoplasm characterized by bone marrow dysplasia, failure of hematopoiesis and variable risk of progression to acute myeloid leukemia (AML). Recent large-scale studies have demonstrated that distinct molecular abnormalities detected at earlier stages of MDS alter disease biology and predict progression to AML. Consistently, various studies analyzing these diseases at the single-cell level have identified specific patterns of progression strongly associated with genomic alterations. These pre-clinical results have solidified the conclusion that high-risk MDS and AML arising from MDS or AML with MDS-related changes (AML-MRC) represent a continuum of the same disease. AML-MRC is distinguished from de novo AML by the presence of certain chromosomal abnormalities, such as deletion of 5q, 7/7q, 20q and complex karyotype and somatic mutations, which are also present in MDS and carry crucial prognostic implications. Recent changes in the classification and prognostication of MDS and AML by the International Consensus Classification (ICC) and the World Health Organization (WHO) reflect these advances. Finally, a better understanding of the biology of high-risk MDS and the mechanisms of disease progression have led to the introduction of novel therapeutic approaches, such as the addition of venetoclax to hypomethylating agents and, more recently, triplet therapies and agents targeting specific mutations, including FLT3 and IDH1/2. In this review, we analyze the pre-clinical data supporting that high-risk MDS and AML-MRC share the same genetic abnormalities and represent a continuum, describe the recent changes in the classification of these neoplasms and summarize the advances in the management of patients with these neoplasms.

EGR1 Haploinsufficiency Confers a Fitness Advantage to Hematopoietic Stem Cells Following Chemotherapy

Therapy-related myeloid neoplasms (t-MNs) share many clinical and molecular characteristics with AML de novo in the elderly. One common factor is that they arise in the setting of chronic inflammation, likely because of advanced age or chemotherapy-induced senescence. Here, we examined the effect of haploinsufficient loss of the del(5q) tumor suppressor gene, EGR1, commonly deleted in high-risk MNs. In mice, under the exogenous stress of either serial transplant or successive doses of the alkylating agent N-ethyl-nitrosourea (ENU), Egr1-haploinsufficient hematopoietic stem cells (HSCs) exhibit a clonal advantage. Complete loss of EGR1 function is incompatible with transformation; mutations of EGR1 are rare and are not observed in the remaining allele in del(5q) patients, and complete knockout of Egr1 in mice leads to HSC exhaustion. Using chromatin immunoprecipitation sequencing (ChIP-seq), we identified EGR1 binding sites in human CD34+ cord blood-derived stem and progenitor cells (HSPCs) and found that EGR1 binds genes critical for stem cell differentiation, inflammatory signaling, and the DNA damage response. Notably, in the chromosome 5 sequences frequently deleted in patients, there is a significant enrichment of innate and inflammatory genes, which may confer a fitness advantage in an inflammatory environment. Short hairpin RNA (shRNA)-mediated silencing of EGR1 biases HSPCs toward a self-renewal transcriptional signature. In the absence of EGR1, HSPCs are characterized by upregulated MYC-driven proliferative signals, downregulated CDKN1A (p21), disrupted DNA damage response, and downregulated inflammation-adaptations anticipated to confer a relative fitness advantage for stem cells especially in an environment of chronic inflammation.

Flow Cytometric Identification of Hematopoietic and Leukemic Blast Cells for Tailored Clinical Follow-Up of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a myeloid malignancy that is characterized by the accumulation of leukemic blast cells, which originate from hematopoietic stem cells that have undergone leukemic transformation and/or are more mature progenitors that have gained stemness features. Currently, no consensus exists for the flow cytometric identification of normal blast cells and their leukemic counterparts by their antigenic expression profile. Differentiating between the benign cells and the malignant cells is crucial for the further deployment of immunophenotype panels for the clinical follow-up of AML patients. This review provides an overview of immunophenotypic markers that allow the identification of leukemic blast cells in the bone marrow with multiparameter flow cytometry. This technique allows the identification of hematopoietic blast cells at the level of maturing cells by their antigen expression profile. While aberrant antigen expression of a single immunophenotypic marker cell cannot be utilized in order to differentiate leukemic blast cells from normal blast cells, combinations of multiple immunophenotypic markers can enable the distinction of normal and leukemic blast cells. The identification of these markers has provided new perspectives for tailored clinical follow-up, including therapy management, diagnostics, and prognostic purposes. The immunophenotypic marker panels, however, should be developed by carefully considering the variable antigen marker expression profile of individual patients.

Oncology stewardship in acute myeloid leukemia

In recent years, an explosion of novel agents has shifted the treatment paradigm for patients with acute myeloid leukemia. The optimal place in therapy for many of these novel agents remains unknown due to limited guidance from national guidelines and the way these agents were studied prior to entering the market. A critical evaluation of the literature and incorporation of oncology stewardship principles can be helpful in determining an optimal place for these agents while being mindful of the overall cost that is associated with therapies. The purpose of this review is to critically evaluate the efficacy and safety data for five controversial agents and provide examples of the use of stewardship practices in determining their place in the treatment of acute myeloid leukemia.

Therapy-related myeloid neoplasms with different latencies: a detailed clinicopathologic analysis

Therapy-related myeloid neoplasm (t-MN) arising in patients with prior cytotoxic treatments is considered a distinct entity due to its unfavorable prognosis. Latencies between the initial cytotoxic therapy and the occurrence of t-MNs vary but usually fall between 1 and 10 years. t-MNs with unusually short or long latencies are not well characterized. It is unclear if they are biologically similar to the ones with ordinary latencies and should be kept in the t-MN entity. We compiled a cohort of t-MN cases including short (<1 year), ordinary (1-10 years), and extended (>10 years) latencies from two tertiary medical centers. Both the t-MNs with ordinary and extended latencies showed high likelihood of high-risk genetic abnormalities and demonstrated no significant survival differences. But the t-MNs with extended latencies were more likely associated with history of multiple cancers (p = 0.007) and were younger at the time of cytotoxic treatments (p < 0.001) when compared to the t-MNs with ordinary latencies. The t-MN with short latencies appears to be a very rare and highly heterogeneous group. In summary, the genetic composition appears similar in the t-MNs with ordinary and extended latencies. However, the association between the t-MN with extended latencies and history of multiple cancers raises a possibility that cancer predisposition may contribute to the accumulation of genetic abnormalities in these patients. Investigation into potential germline mutations in the t-MN patients with extended latencies may provide important information for related family members.

Phase 1/2 study of uproleselan added to chemotherapy in patients with relapsed or refractory acute myeloid leukemia

Uproleselan (GMI-1271) is a novel E-selectin antagonist that disrupts cell survival pathways, enhances chemotherapy response, improves survival in mouse xenograft and syngeneic models, and decreases chemotherapy toxicity in vivo. A phase 1/2 study evaluated the safety, tolerability, and antileukemic activity of uproleselan (5-20 mg/kg) with MEC (mitoxantrone, etoposide, and cytarabine) among patients with relapsed/refractory (R/R) acute myeloid leukemia (AML). Among the first 19 patients, no dose-limiting toxicities were observed. The recommended phase 2 dose (RP2D) was 10 mg/kg twice daily. An additional 47 patients with R/R AML were treated with uproleselan at the RP2D plus MEC. At the RP2D, the remission rate (complete response [CR]/CR with incomplete count recovery [CRi]) was 41% (CR, 35%), and the median overall survival (OS) was 8.8 months. In a separate cohort, 25 newly diagnosed patients age ≥60 years received uproleselan at the RP2D plus cytarabine and idarubicin (7 + 3). In these frontline patients, the CR/CRi rate was 72% (CR, 52%), and the median OS was 12.6 months. The addition of uproleselan was associated with low rates of oral mucositis. E-selectin ligand expression on leukemic blasts was higher in patients with relapsed vs primary refractory AML and in newly diagnosed older patients with high-risk cytogenetics and secondary AML. In the R/R cohort, E-selectin expression >10% was associated with a higher response rate and improved survival. The addition of uproleselan to chemotherapy was well tolerated, with high remission rates, low induction mortality, and low rates of mucositis, providing a strong rationale for phase 3 randomized confirmatory studies. This trial was registered at www.clinicaltrials.gov as #NCT02306291.

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.

Impact of induction chemotherapy with intermediate-dosed cytarabine and subsequent allogeneic stem cell transplantation on the outcome of high-risk acute myeloid leukemia

Background

Acute myeloid leukemia (AML) with antecedent hematological disease (s-AML) and treatment-related AML (t-AML) predicts poor prognosis. Intensive treatment protocols of those high-risk patients should consider allogeneic stem cell transplantation (allo-HSCT) in first complete remission (CR). Despite allo-HSCT, relapse rate remains high. Induction chemotherapy with liposomal cytarabine and daunorubicin (CPX-351) has been approved for patients with AML with myeloid-related changes (AML-MRC) or t-AML based on improved survival and remission rates compared to standard 7 + 3 induction.

Patients and methods

110 patients with newly diagnosed s-AML or t-AML at a university hospital were analyzed retrospectively. Median age was 62 years (24–77 years). A total of 65 patients with s-AML after MDS (59%) and 23 patients (20.9%) with t-AML were included. Induction chemotherapy consisted of intermediate-dosed cytarabine (ID-AraC) in combination with idarubicin (patients up to 60 years) or mitoxantrone (patients over 60 years). In patients subsequently undergoing allo-HSCT, reduced conditioning regimens (RIC) were applied prior to transplantation in 47 of 62 patients (76%).

Results

Induction chemotherapy with ID-AraC resulted in an overall response rate of 83% including complete remission (CR/CRi) in 69 patients (63%) with a low rate of early death (2.7%). Most relevant non-hematologic toxicity consisted of infectious complications including sepsis with need of intensive care treatment in five patients (4.5%) and proven or probable invasive fungal disease in eight patients (7.2%). Relapse-free survival (RFS), event-free survival (EFS) and overall survival (OS) of the whole cohort were 19 months (0–167), 10 months (0–234) and 15 months (0–234), respectively (p < 0.0001). A significant improvement of OS was observed in patients who underwent allo-HSCT compared to those without subsequent allo-HSCT: 9 vs. 46 months, p < 0.0001. Rate of transplantation-related mortality (TRM) in the early phase post allo-HSCT was low (0.9% at day 30 and 1.8% at day 90, respectively). RIC conditioning results in OS rate of 60% after 60 months post allo-HSCT (median OS not reached).

Conclusion

S-AML and t-AML patients receiving induction chemotherapy with intermediate-dosed cytarabine showed satisfactory response rate and consolidation therapy with allo-HSCT after full or reduced-intensity conditioning further improved survival in these patients with similar outcome as reported for CPX-351.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03733-0.

Case Report: Combination Therapy With PD-1 Blockade for Acute Myeloid Leukemia After Allogeneic Hematopoietic Stem Cell Transplantation Resulted in Fatal GVHD

Background: Azacitidine is commonly used in the treatment of relapsed acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), but the effectiveness of this monotherapy is still very low. A possible mechanism of resistance to hypomethylating agents (HMAs) is the upregulation of the expression of inhibitory checkpoint receptors and their ligands, making the combination of HMAs and immune checkpoint blockade therapy a rational approach. Although the safety of anti-programmed cell death protein (PD)-1 antibodies for patients with post-allo-HSCT remains a complicated issue, the preliminary clinical result of combining azacitidine with anti-PD-1 antibodies is encouraging; however, the safety and efficacy of this approach need further investigation. Case Presentation: We reported a case of treated secondary (ts)-AML in a patient who received tislelizumab (an anti-PD-1 antibody) in combination with azacitidine. The patient relapsed after allo-HSCT and was previously exposed to HMAs-based therapy. The patient received tislelizumab for compassionate use. After the combination treatment, the patient achieved complete remission with incomplete hematologic recovery, negative minimal residual disease (MRD) by flow cytometry (FCM), and negative Wilms' tumor protein 1 (WT1). However, the patient successively developed serious immune-related adverse events (irAEs) and graft vs. host disease (GVHD) and eventually died from complications of GVHD. Conclusion: To our knowledge, this is the first case to report the combined use of tislelizumab and azacitidine to treat relapsed AML posttransplantation. This report highlights the safety concerns of using an anti-PD-1 antibody in combination with azacitidine after allo-HSCT, especially the risk of GVHD, and provides a basis for future studies.

Secondary AML Emerging After Therapy with Hypomethylating Agents: Outcomes, Prognostic Factors, and Treatment Options

PURPOSE OF REVIEW

Secondary AML (s-AML) encompasses a distinct subgroup of AML with either therapy-related AML or AML arising from preexisting myeloid neoplasms. Despite recent advances in the treatment armamentarium of AML, outcomes remain poor in s-AML. The purpose of this review is to highlight distinct characteristics, prognostic factors, and treatment options for patients with s-AML. Further, we focus on a distinctly poor-risk subgroup of s-AML with previous exposure to hypomethylating agents (HMAs) and describe ongoing clinical trials in this patient population.

RECENT FINDINGS

CPX-351 (liposomal daunorubicin and cytarabine) is the first drug approved for s-AML and represents an advancement in the management of fit patients with this subtype of AML. Despite incremental improvement in remission rates and survival, long-term survival remains poor. Patients who have received prior HMAs for antecedent MDS rarely benefit from CPX-351 or other cytotoxic chemotherapy regimens. The approval of venetoclax in combination with azacitidine has led to a paradigm shift in the management of newly diagnosed older unfit AML patients; however, patients with s-AML and prior HMA therapy were excluded from the landmark randomized phase 3 study. Several early phase clinical trials with both low- and high-intensity therapies are ongoing for s-AML patients, though prior HMA exposure limits inclusion in many of these studies that include HMAs. Patients with s-AML previously treated with an HMA have dismal outcomes with standard therapeutic options and are under-represented in clinical trials. Trials investigating novel therapeutic options in this population are critically needed.

Case report of combination therapy with Azacytidine, Enasidenib and Venetoclax in primary refractory AML

Optimal treatment of acute myeloid leukemia (AML) arising in elderly patients remains a challenge. FDA approval of Ivosidenib and Enasidenib, small molecule inhibitors of isocitrate dehydrogenase enzymes (IDH1 and 2) have opened new avenues of treatment. We present a 60-year-old woman with refractory AML, achieving complete response to the combination therapy of hypomethylating agent, Azacytidine with the IDH2 inhibitor, Enasidenib, and BCL2 inhibitor, Venetoclax. To our knowledge, this is the first case report of a patient with IDH2 mutated refractory AML achieving complete response to combination therapy with azacytidine, enasidenib and venetoclax.

How to address second and therapy-related acute myelogenous leukaemia

Secondary acute myelogenous leukaemia (AML), as compared to de novo AML, occurs in the more elderly population, is independently more resistant to cytotoxic chemotherapy, has a higher relapse rate, and a worse prognosis. Secondary AML (sAML) is a heterogeneous disease, both biologically and clinically, even within the World Health Organization subgroups of sAML. Outcomes are the poorest in subgroups with sAML arising from an antecedent haematologic disorder which has been previously treated (ts-AML), and sAML in patients <55 years of age. This review describes the suboptimal outcomes of contemporary therapy, to support the notion of an unmet need for innovative treatment strategies in sAML. Despite the recent approval of CPX-351, long-term outcomes for this high-risk disease remain dismal. Resistance mechanisms to intensive chemotherapy contribute to relapse. Targeted immune therapy may avoid multidrug resistance mechanisms, but are unlikely to provide long-term remission due to a complex and rapidly evolving clonal disease profile. Advances for sAML will likely be accomplished by CAR T cell therapy or bispecific antibodies providing a bridge to allogeneic stem cell transplantation. Therefore, focus should be placed on novel strategies that can augment the untargeted effector function of allogeneic grafts.

A phase 1 study of azacitidine with high-dose cytarabine and mitoxantrone in high-risk acute myeloid leukemia

In this phase 1 study, azacitidine (AZA) was given before high-dose cytarabine (HiDAC) and mitoxantrone (mito) based on the hypothesis that epigenetic priming with a hypomethylating agent before cytotoxic chemotherapy would improve response rates in patients with high-risk acute myeloid leukemia (AML), including relapsed/refractory disease. The primary objective was to establish the recommended phase 2 dose of AZA given before standard HiDAC/mito. In a dose escalation scheme, 46 patients (median age, 66 years) received AZA at 37.5, 50, or 75 mg/m2 subcutaneously or IV once daily on days 1 to 5 followed by HiDAC (3000 mg/m2) and mitoxantrone (30 mg/m2) once each on days 6 and 10 (the HiDAC/mito dose was reduced 33% in elderly subjects). Two dose-limiting toxicities occurred (both in the same patient): acute liver failure and kidney injury at the 50 mg/m2 dose. The 30-day induction death rate was 2.2% (1 of 46). The overall response rate, including complete remission and complete remission with incomplete count recovery, was 61% (28 of 46). Previously untreated patients aged ≥60 years with therapy-related AML and de novo AML were more likely to respond than untreated patients with AML progressing from an antecedent hematologic disorder (myelodysplastic syndrome and chronic myelomonocytic leukemia). Patients with favorable European Leukemia Network risk (P = .008), NPM1 mutations (P = .007), or IDH2 mutations (P = .03) were more likely to respond, and those with TP53 mutations (P = .03) were less likely to respond. The recommended phase 2 dose of AZA is 75 mg/m2 per day on days 1 to 5 followed by HiDAC (3000 mg/m2) and mitoxantrone (30 mg/m2) once each on days 6 and 10. This trial was registered at www.clinicaltrials.gov as #NCT01839240.

Comparisons of commonly used front-line regimens on survival outcomes in patients aged 70 years and older with acute myeloid leukemia

In older patients with acute myeloid leukemia, the more frequent presence of biologically inherent therapy-resistant disease and increased comorbidities translate to poor overall survival and therapeutic challenges. Optimal front-line therapies for older patients with acute myeloid leukemia remain controversial. We retrospectively evaluated survival outcomes in 980 elderly (≥70 years) acute myeloid leukemia patients from a single institution between 1995 and 2016. Four treatment categories were compared: high-intensity (daunorubicin/cytarabine or equivalent), hypomethylating agent, low-intensity (low-dose cytarabine or similar without hypomethylating agents), and supportive care therapy (including hydroxyurea). At a median follow up of 20.5 months, the median overall survival for the entire cohort was 7.1 months. Multivariate analysis identified secondary acute myeloid leukemia, poor-risk cytogenetics, performance status, front-line therapy, age, white blood cell count, platelet count, and hemoglobin level at diagnosis as having an impact on survival. High-intensity therapy was used in 360 patients (36.7%), hypomethylating agent in 255 (26.0%), low-intensity therapy in 91 (9.3%), and supportive care in 274 (28.0%). Pairwise comparisons between hypomethylating agent therapy and the three other treatment groups demonstrated statistically significant superior median overall survival with hypomethylating agent [14.4 months) vs. high-intensity therapy 10.8 months, hazard ratio 1.35, 95% confidence interval (CI): 1.10-1.65; P =0.004], low-intensity therapy (5.9 months, hazard ratio 2.01, 95%CI: 1.53-2.62; P<0.0001), and supportive care (2.1 months, hazard ratio 2.94, 95%CI: 2.39-3.61; P<0.0001). Our results indicate a significant survival benefit with hypomethylating agents compared to high-intensity, low-intensity, or supportive care. Additionally, high-intensity chemotherapy resulted in superior overall outcomes compared to low-intensity therapy and supportive care. Results from this study highlight the need for novel therapeutic approaches besides utilization of intensive chemotherapy in this specific aged population.

Metformin inhibits cell proliferation in SKM-1 cells via AMPK-mediated cell cycle arrest

Metformin, a widely used antidiabetic drug, has previously been demonstrated to exert anti-cancer effects in certain hematological malignancies, but its effects on the transformation of myelodysplastic syndromes to acute myeloid leukemia (AML-MDS) remain unclear. The present study aimed to investigate the effects of metformin on SKM-1 cells (an AML-MDS cell line) and its underlying mechanisms. SKM-1 cells were treated with different concentrations of metformin. Cell proliferation was assayed by CCK-8. Apoptosis and cell cycle phases were detected by flow cytometry, while cell cycle related proteins and AMPK were tested by Western blot. SKM-1 cells were transfected with LV-AMPKα1-RNAi to reduce the expression of AMPK. Metformin inhibited cell proliferation in a dose and time dependent manner by inducing G0/G1 phase arrest rather than apoptosis induction. Metformin promoted the expression of p-AMPK, P53, P21^CIP1 and P27^KIP1, while inhibited the expression of CDK4 and CyclinD1. AMPK knockdown attenuated the effects of metformin on SKM-1 cells. These findings suggested that metformin inhibited proliferation of SKM-1 cells, potentially through an AMPK-mediated cell cycle arrest.

Evaluation of induction chemotherapies after hypomethylating agent failure in myelodysplastic syndromes and acute myeloid leukemia

Hypomethylating agent (HMA) failure in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) carries a poor prognosis with limited treatment options. Although intensive, remission induction chemotherapy is often used subsequently, in particular to bridge to allogeneic transplantation, it is not clear whether an advantage exists for any particular regimen. Based on an international collaboration, we retrospectively analyzed induction response rate and survival in 366 patients after HMA failure. Patients received 7+3, intermediate- to high-dose cytarabine (IDAC), or purine nucleoside analog-based regimens. For the MDS cohort (n = 307), the overall response rate (ORR) was 41%; median overall survival (OS) was 10.8 months, and 40% of responding patients bridged to allogeneic stem cell transplant (allo-SCT). For the AML cohort (n = 59), the ORR was 32%, OS 6 months, and 42% of responding patients bridged to allo-SCT. Prognostic factors for response in MDS included adverse cytogenetics (odds ratio [OR], 0.46, P = .01), age ≥65 years (OR, 0.47; P < .01), and use of IDAC (OR, 2.91, P = .01). Shorter survival was associated with adverse cytogenetics (hazard ratio [HR], 1.43; P = .06). In the AML cohort, OS was decreased by disease progression at time of HMA failure (HR, 2.66; P = .02) and prolonged with use of an anthracycline-containing regimen (HR, 0.37; P = .01). In conclusion, intensive chemotherapy after HMA failure may be a reasonable treatment option for selected patients as a bridge to allogeneic transplantation and should be considered a potential platform for future investigations.

Can we predict responsiveness to hypomethylating agents in AML?

DNA-hypomethylating agents (HMAs) were developed as nonintensive treatment alternatives to standard chemotherapy in older, unfit patients with acute myeloid leukemia and myelodysplastic syndrome. Given their distinct effects on the methylome and transcriptome of malignant cells compared to cytarabine (Ara-C) and other cytotoxic drugs not inhibiting DNA methyltransferases, it is of great interest to define their specific clinical ``signature.'' Here, we present and discuss clinical, genetic, and epigenetic predictors of responsiveness to HMAs. Indeed, mounting evidence supports the notion that HMAs are not "just another kind of low-dose Ara-C." Not only patient factors (age, performance status, comorbidities, etc.), blast counts, and early platelet response, but also adverse genetics (monosomal karyotype and/or a TP53 mutation) have predictive potential. Given the surprising-and initially counterintuitive-responses observed in patients with the latter features, these are subject to mechanistic studies to elucidate their as yet unresolved interaction with HMAs. Finally, other potential biomarkers for HMA response such as elevated fetal hemoglobin might also contribute to overcome the present challenges in predicting responsiveness to HMAs.

Upfront allogeneic hematopoietic cell transplantation (HCT) versus remission induction chemotherapy followed by allogeneic HCT for acute myeloid leukemia with multilineage dysplasia: A propensity score matched analysis

The efficacy of induction chemotherapy before allogeneic hematopoietic cell transplantation (HCT) for patients with acute myeloid leukemia with multilineage dysplasia (AML-MLD) is unclear. Some patients with AML-MLD have received upfront HCT without prior induction chemotherapy. To compare the transplant outcomes between patients who received upfront HCT and those who received induction chemotherapy followed by allogeneic HCT for AML-MLD, we retrospectively analyzed the Japanese registration data of 1445 adult patients who had received allogeneic HCT between 2007 and 2016. Propensity score matching identified 269 patients in each cohort. There were no significant differences in overall survival between the two groups. The cumulative incidence of leukemia-related mortality was significantly lower in patients who received upfront HCT than those who received induction chemotherapy before HCT. In the subgroup analyses, upfront HCT had a significantly reduced incidence of leukemia-related mortality among patients aged between 60 and 70 years, those with a lower white blood cell count at diagnosis (<3000/μL), and poor cytogenetic risk, and those who received myeloablative conditioning and cord blood transplantation. Our results suggested that induction chemotherapy before HCT did not have any benefits of survival after HCT for AML-MLD. Upfront HCT contributed to the reduced incidence of leukemia-related mortality after HCT. Upfront HCT should be considered for patients with AML-MLD who are eligible for allogeneic HCT.

Acute myeloid leukemia: 2019 update on risk-stratification and management

Outcome in patients with acute myeloid leukemia (AML) ranges from death within a few days of beginning treatment (treatment related mortality, TRM) to likely cure. The major reason patients are not cured is resistance to treatment, often manifested as relapse from remission, rather than, even in older patients, TRM, whose incidence is decreasing. Knowledge of the pre-treatment mutation status of various genes has improved our ability to assign initial treatment and, of particular importance, knowledge of whether patients ostensibly in remission have measurable residual disease should influence subsequent management. Several new drugs have been approved by the FDA and we discuss their role in treatment.

The FOSSIL Study: FLAG or standard 7+3 induction therapy in secondary acute myeloid leukemia

Patients with secondary acute myeloid leukemia (sAML) have poor outcomes, with CR/CRi rates of 25-35% with standard 7 + 3 induction chemotherapy, while single center non-comparative analyses suggest promising outcomes with FLAG. We conducted a single-center, retrospective cohort study assessing outcomes in treatment-naïve patients with sAML treated with fludarabine, high-dose cytarabine, and granulocyte colony-stimulating factor (FLAG, n = 40) compared with 7 + 3 (n = 66). Median patient age was 63 years (range: 27-82) in the FLAG group and 60 years (range: 21-76) in the 7 + 3 group (P = 0.968). Patients treated with FLAG achieved higher overall response rates (CR + CRi + MLFS) compared to 7 + 3 (70% vs. 48%, P = 0.043). FLAG was well tolerated, with only one induction death (30-day mortality rate, 3% vs. 8%, P = 0.405) and no cases of cerebellar toxicity. Duration of neutropenia was significantly shorter with FLAG (median 16 vs. 23 days, P < 0.001). Half of the FLAG-treated patients proceeded to consolidative therapy compared with only 27% of those who received 7 + 3 (P = 0.022). Overall survival was comparable between groups (8.5 mos, FLAG vs. 9.1 mos, 7 + 3; P = 0.798). Thus, FLAG may represent a low-cost treatment strategy in sAML that produces higher response rates and promising survival outcomes with minimal treatment-related toxicity. Further studies are required to prospectively compare FLAG to the newly FDA-approved CPX-351 in sAML.

Acute Myeloid Leukemia: The Good, the Bad, and the Ugly

Acute myeloid leukemia (AML) was initially subdivided according to morphology (the French-American-British system), which proved helpful in pathologic categorization. Subsequently, clinical and genomic factors were found to correlate with response to chemotherapy and with overall survival. These included a history of antecedent hematologic disease, a history of chemotherapy or radiation therapy, the presence of various recurrent cytogenetic abnormalities, and, more recently, the presence of specific point mutations. This article reviews the biology and responses of one AML subgroup with consistent response and good outcomes following chemotherapy (core-binding factor leukemia), and two subgroups with persistently bad, and even ugly, outcomes (secondary AML and TP53-mutated AML).

Phase 1/2 trial of GCLAM with dose-escalated mitoxantrone for newly diagnosed AML or other high-grade myeloid neoplasms

Outcomes with “7+3” are often unsatisfactory in acute myeloid leukemia (AML). Trials demonstrating improved outcomes with high-dose cytarabine, addition of cladribine, or escalated anthracycline doses prompted a phase 1/2 study (NCT02044796) of G-CSF, cladribine, high-dose cytarabine, and dose-escalated mitoxantrone (GCLAM) in adults with newly-diagnosed AML or other high-grade myeloid neoplasms. 121 patients, median age 60 (range: 21–81) years, were enrolled. In phase 1, cohorts of 6–12 patients were assigned to 12–18mg/m²/day of mitoxantrone as part of GCLAM. Because all dose levels were well-tolerated, mitoxantrone at 18mg/m² was declared the recommended phase 2 dose (RP2D). 74/94 (79%) patients treated at the RP2D achieved a complete remission (CR; 67/74 without measureable residual disease [MRD]) for an overall MRD^neg CR rate of 71% (primary phase 2 endpoint). Seven patients achieved a CR with incomplete blood count recovery (CRi; 7%, 5 MRD^neg) for a CR/CRi rate of 81/94 (86%). 4-week mortality was 2%. After adjustment, the MRD^neg CR and CR/CRi rates compared favorably to 100 matched controls treated with 7+3 at our center and 245 matched patients treated with 7+3 on a cooperative group trial. Our data indicate GCLAM with mitoxantrone at 18mg/m²/day is safe and induces high-quality remissions in adults with newly-diagnosed AML.

Therapy-related myeloid neoplasms: when genetics and environment collide

Therapy-related myeloid neoplasms (t-MN) arise as a late effect of chemotherapy and/or radiation administered for a primary condition, typically a malignant disease, solid organ transplant or autoimmune disease. Survival is measured in months, not years, making t-MN one of the most aggressive and lethal cancers. In this Review, we discuss recent developments that reframe our understanding of the genetic and environmental aetiology of t-MN. Emerging data are illuminating who is at highest risk of developing t-MN, why t-MN are chemoresistant and how we may use this information to treat and ultimately prevent this lethal disease.

Treated secondary acute myeloid leukemia: a distinct high-risk subset of AML with adverse prognosis

Secondary acute myeloid leukemia (s-AML) includes therapy-related AML and AML evolving from antecedent hematological disorder (AHD). s-AML arising after treating AHD likely represents a prognostically distinct, high-risk disease category. In this study, treated s-AML (ts-AML) was defined by: (1) prior diagnosis of myelodysplasia, myeloproliferative neoplasm, or aplastic anemia and (2) at least 1 therapy for that diagnosis. ts-AML was categorized by age (< or ≥60 years), and each cohort assessed for response rates and overall survival (OS) on various treatment regimens. Survival outcomes were compared against other high-risk prognostic subsets. Results showed that complete response and 8-week mortality rates were 32% and 27% in the younger, and 24% and 19% in the older age groups, respectively. There was a significant OS difference within s-AML based on prior treatment of AHD (ie, ts-AML vs s-AML with untreated AHD, 4.2 vs 9.2 months; P < .001). Survival in ts-AML was poor across both cohorts (younger and older, 5 and 4.7 months, respectively). In younger AML, survival was significantly inferior in ts-AML when compared with deletion 5/7, TP53, 3q abnormality, and therapy-related AML groups (median, 5 vs 7.9, 7.8, 7.9, and 11.2 months, respectively; P < .01). Additional adverse karyotype within ts-AML was associated with even worse outcomes (OS range, 1.6-2.8 months). ts-AML represents a very high-risk category, even in younger AML patients. s-AML should be further classified to describe ts-AML, an entity less responsive to currently applied treatment approaches. Future AML trial designs should accommodate ts-AML as a distinct subgroup.

Assessment of Drug Sensitivity in Hematopoietic Stem and Progenitor Cells from Acute Myelogenous Leukemia and Myelodysplastic Syndrome Ex Vivo

Current understanding suggests that malignant stem and progenitor cells must be reduced or eliminated for prolonged remissions in myeloid neoplasms such as acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS). Multicolor flow cytometry has been widely used to distinguish stem and myeloid progenitor cells from other populations in normal and malignant bone marrow. In this study, we present a method for assessing drug sensitivity in MDS and AML patient hematopoietic stem and myeloid progenitor cell populations ex vivo using the investigational Nedd8‐activating enzyme inhibitor MLN4924 and standard‐of‐care agent cytarabine as examples. Utilizing a multicolor flow cytometry antibody panel for identification of hematopoietic stem cells, multipotent progenitors, common myeloid progenitors, granulocyte‐monocyte progenitors, and megakaryocyte‐erythroid progenitors present in mononuclear cell fractions isolated from bone marrow aspirates, we compare stem and progenitor cell counts after treatment for 24 hours with drug versus diluent. We demonstrate that MLN4924 exerts a cytotoxic effect on MDS and AML stem and progenitor cell populations, whereas cytarabine has more limited effects. Further application of this method for evaluating drug effects on these populations ex vivo and in vivo may inform rational design and selection of therapies in the clinical setting. Stem Cells Translational Medicine2017;6:840–850

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.

Emerging strategies for the treatment of older patients with acute myeloid leukemia

Acute myeloid leukemia (AML) is the most common acute leukemia in adults, and its incidence increases with age. Clinical outcomes in younger patients have improved over the years but, unfortunately, there is little evidence for an equivalent improvement in outcome for older patients. Approximately 50 % of older patients who are able to receive intensive chemotherapy will achieve a complete remission; however, they face a much higher relapse rate than younger patients, and survival rates for this group are low. Therefore, there is an urgent need to improve outcomes in older patients with AML. In this article, we discuss current treatment paradigms for older patients with AML including the challenges faced when determining which patients are eligible for intensive chemotherapy. We then highlight new treatments in development that may benefit this patient group. Cytotoxic agents, hypomethylating agents, molecularly targeted agents, and cell cycle kinase inhibitors are discussed, with a focus on novel agents that have achieved an advanced stage of development. Overall, the treatment of AML in older patients remains a challenge and, whenever possible, treatment should be offered in the context of clinical trials and should be planned with curative intent.

Rigosertib versus best supportive care for patients with high-risk myelodysplastic syndromes after failure of hypomethylating drugs (ONTIME): a randomised, controlled, phase 3 trial

BACKGROUND

Hypomethylating drugs are the standard treatment for patients with high-risk myelodysplastic syndromes. Survival is poor after failure of these drugs; there is no approved second-line therapy. We compared the overall survival of patients receiving rigosertib and best supportive care with that of patients receiving best supportive care only in patients with myelodysplastic syndromes with excess blasts after failure of azacitidine or decitabine treatment.

METHODS

We did this randomised controlled trial at 74 hospitals and university medical centres in the USA and Europe. We enrolled patients with diagnosis of refractory anaemia with excess blasts (RAEB)-1, RAEB-2, RAEB-t, or chronic myelomonocytic leukaemia based on local site assessment, and treatment failure with a hypomethylating drug in the past 2 years. Patients were randomly assigned (2:1) to receive rigosertib 1800 mg per 24 h via 72-h continuous intravenous infusion administered every other week or best supportive care with or without low-dose cytarabine. Randomisation was stratified by pretreatment bone marrow blast percentage. Neither patients nor investigators were masked to treatment assignment. The primary outcome was overall survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT01241500.

FINDINGS

From Dec 13, 2010, to Aug 15, 2013, we enrolled 299 patients: 199 assigned to rigosertib, 100 assigned to best supportive care. Median follow-up was 19·5 months (IQR 11·9-27·3). As of Feb 1, 2014, median overall survival was 8·2 months (95% CI 6·1-10·1) in the rigosertib group and 5·9 months (4·1-9·3) in the best supportive care group (hazard ratio 0·87, 95% CI 0·67-1·14; p=0·33). The most common grade 3 or higher adverse events were anaemia (34 [18%] of 184 patients in the rigosertib group vs seven [8%] of 91 patients in the best supportive care group), thrombocytopenia (35 [19%] vs six [7%]), neutropenia (31 [17%] vs seven [8%]), febrile neutropenia (22 [12%] vs ten [11%]), and pneumonia (22 [12%] vs ten [11%]). 41 (22%) of 184 patients in the rigosertib group and 30 (33%) of 91 patients in the best supportive care group died due to adverse events and three deaths were attributed to rigosertib treatment.

INTERPRETATION

Rigosertib did not significantly improve overall survival compared with best supportive care. A randomised phase 3 trial of rigosertib (NCT 02562443) is underway in specific subgroups of patients deemed to be at high risk, including patients with very high risk per the Revised International Prognostic Scoring System criteria.

FUNDING

Onconova Therapeutics, Leukemia & Lymphoma Society.

Prior hypomethylating agent use lacks impact on clinical outcome in patients with secondary acute myeloid leukemia arising from myelodysplastic syndromes treated with standard induction chemotherapy

Patients with secondary acute myeloid leukemia (sAML) arising from prior myelodysplastic syndromes have poor prognosis. Anthracycline plus cytarabine (7 + 3) is a standard treatment option for patients who are fit for intensive therapy. In the present study, 22 of 96 sAML patients (23 %) were treated with 7 + 3 and achieved median overall survival (OS) of 9.8 months. Hypomethylating agents (HMA) were given for MDS in 6/22 (28 %) of the patients. When evaluating the prior HMA group, CR/CRi was 50 % for those with prior HMA exposure and 63 % for those without HMA exposure (P = 0.6). Median OS was 14 months for prior HMA exposure vs 10 months for no prior HMA (P = 0.9). The outcome of sAML patients who were treated with 7 + 3 continues to be poor. No statistical significant difference was found between response rates and mOS between prior HMA exposure or not. Additional larger studies are needed to confirm our results.

Searching for a Light at the End of the Tunnel? Beyond Hypomethylating Agents in Myelodysplastic Syndromes

Hypomethylating agents (HMAs) are the mainstay treatment of patients with myelodysplastic syndromes. Hypomethylating agents remain the only treatment, other than allogeneic hematopoietic stem cell transplantation (AHSCT), that improves overall survival (OS) for patients with higher-risk myelodysplastic syndromes. It is crucial to maximize the benefit of HMAs by selecting the appropriate dosing and schedule and continuing therapy until clear evidence of lack of response or failure of therapy. Strategies to improve outcome with HMAs include identifying tools and biomarkers for better patient selection, namely the ability to identify those who achieve complete response (CR) or long duration of response, combination strategies with HMAs aim to improve response rate or its duration. The outcome of patients with myelodysplastic syndromes after HMA failure is poor for both patients with higher-risk and lower-risk disease and represents an unmet medical need. The best outcomes after HMA failure are reported with AHSCT or novel agents in clinical trials. This article discusses the maximizing benefit of HMAs, offers strategies to improve outcome with HMAs, and, finally, reviews selected novel agents in development after HMA failure.

Sequential azacitidine plus lenalidomide in previously treated elderly patients with acute myeloid leukemia and higher risk myelodysplastic syndrome

The outcome of sequential azacitidine with lenalidomide has not been reported in previously treated patients with acute myeloid leukemia (AML) and higher risk myelodysplastic syndrome (MDS). This study describes a phase 2 study evaluating the safety and efficacy of this combination in elderly patients with AML and MDS with prior hypomethylating agent (HMA) and/or immunomodulatory agent exposure. Patients were treated on a 42-day cycle with azacitidine at 75 mg/m2 SQ/IV daily on days 1-7, followed by lenalidomide 50 mg orally daily on days 8-28. The median number of treatment cycles on study was two (range = 1-11). Of 32 evaluable patients, the overall response rate was 25%. Neutropenic fever was the most common serious adverse event, but overall the combination was well-tolerated. The median overall survival (OS) for responders vs non-responders was 9.8 vs 4.0 months, respectively (HR = 0.36, p = 0.016). In conclusion, this combination demonstrated modest clinical activity in this poor risk population.

Allo-SCT for myelofibrosis: reversing the chronic phase in the JAK inhibitor era?

At present, allo-SCT is the only curative treatment for patients with myelofibrosis (MF). Unfortunately, a significant proportion of candidate patients are considered transplant ineligible due to their poor general condition and advanced age at the time of diagnosis. The approval of the first JAK inhibitor, ruxolitinib, for patients with advanced MF in 2011 has had a qualified impact on the treatment algorithm. The drug affords substantial improvement in MF-associated symptoms and splenomegaly but no major effect on the natural history. There has, therefore, been considerable support for assessing the drug's candidacy in the peritransplant period. The drug's precise impact on clinical outcome following allo-SCT is currently not known; nor are the drug's long-term efficacy and safety known. Considering the rarity of MF and the small proportion of patients who undergo allo-SCT, well designed collaborative efforts are required. In order to address some of the principal challenges, an expert panel of laboratory and clinical experts in this field was established, and an independent workshop held during the 54th American Society of Hematology Annual Meeting in New Orleans, USA on 6 December 2013, and the European Hematology Association's Annual Meeting in Milan, Italy on 13 June 2014. This document summarizes the results of these efforts.

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.

Up-front allogeneic hematopoietic cell transplantation in acute myeloid leukemia arising from the myelodysplastic syndrome

In patients with secondary acute myeloid leukemia (s-AML) arising from the myelodysplastic syndrome (MDS), treatment outcome is unsatisfactory. We compared up-front allogeneic hematopoietic cell transplantation (HCT) to induction chemotherapy (IC) as an initial treatment in patients with s-AML arising from MDS. This retrospective study included 85 patients who were diagnosed with s-AML arising from MDS; 11 patients proceeded to up-front HCT without IC (HCT group) and 74 received IC (IC group) as an initial treatment for s-AML, 28 of whom subsequently underwent HCT. In the IC group, 41.9% achieved complete remission (CR) compared to 81.8% in the HCT group (p = 0.013). The HCT group showed a significantly longer event-free survival (EFS) than the IC group (median 29.2 vs. 5.2 months, p = 0.042). Overall survival of the HCT group was higher than that of the IC group, but the difference was not statistically significant (median 34.6 vs. 7.6 months, p = 0.149). After adjustment for other clinical factors, outcome in the HCT group was significantly better than in the IC group in terms of CR rate (hazard ratio, HR, 11.195; p = 0.007) and EFS (HR, 0.384; p = 0.029). Up-front HCT is a viable option in s-AML arising from MDS if an appropriate donor is available.

Minimizing risk of hypomethylating agent failure in patients with higher-risk MDS and practical management recommendations

In Europe, azacitidine is the only hypomethylating agent approved for the treatment of patients with int-2-/high-risk myelodysplastic syndromes, offering significantly improved survival compared with conventional care. However, not all patients treated with azacitidine respond to treatment, and the vast majority of responders subsequently relapse. Currently, no standard care regimens have been established for patients after failure of azacitidine. Here, we discuss treatment options after loss of response or progression on azacitidine. In addition, we briefly consider optimization of first-line treatment along with potential biomarkers for identifying and monitoring response during treatment with azacitidine.

Characteristics and clinical evolution of patients with acute myeloblastic leukemia in northeast Mexico: an eight-year experience at a university hospital

BACKGROUND/OBJECTIVE

Acute myeloid leukemia (AML) is the most common acute leukemia in adults. We documented the characteristics and results of treatment of patients with AML at a single reference center.

METHODS

Patients diagnosed with AML between June 2003 and July 2011 at a university hospital in northeast Mexico were studied. Overall survival (OS) and event-free survival (EFS) were determined, and risk factors were analyzed with respect to their influence on prognosis.

RESULTS

A total of 132 AML patients were included. Median age was 32 years. Complete remission (CR) was achieved by 55% of patients. CR was achieved by 65.1% of patients <60 years (n = 109), compared to 8.7% of those >60 years (n = 23; p < 0.001). In all, 39% of patients >60 years suffered an early death, compared to 14.7% of those <60 years (p < 0.001). OS for patients with AML was 35%, whereas EFS was 32%. On multivariate analysis, patients >60 years had a lower OS and EFS (p < 0.001). A total of 28% of patients received a transplant, and they had high er OS and EFS. Conclusions: Our patients were considerably younger and had remarkably lower survival rates than reported for other populations; those >60 years had a higher early death rate, and fewer of these patients achieved CR.

Phase II clinical study of erlotinib for treatment of myelodysplastic syndromes

Outcome in patients with myelodysplastic syndrome (MDS) after azanucleoside failure is poor with unmet need for active novel agents. Preclinical data have suggested that erlotinib has in vivo and in vitro off epidermal growth factor receptor (EGFR)-target activity in MDS. We conducted a phase II study with single-agent erlotinib 150 mg/day orally in MDS patients following azanucleoside failure. All intermediate-2 or high-risk MDS patients by International Prognostic Scoring System and only those low/intermediate-1 patients with transfusion-dependent anemia or platelet counts <50 × 10(9) /L or a significant clinical hemorrhage requiring platelet transfusion or ANC <1 × 10(9) /L were eligible, with most of our patients being at high risk. In 35 eligible patients, overall best response was 14% (3 patients having marrow complete response and 2 hematological improvement). Four deaths occurred on study (sepsis, intracranial hemorrhage, sudden death, and acute myeloid leukemia (AML)). The most common observed grade 3/4 toxicities according to CTCAE v3 were diarrhea (17.1%), rash (17.1%), and infection (11.6%), accompanied by fatigue, thrombocytopenia, and anorexia at 5.7% each. Median overall survival was 6.8 months (95% CI 4.9-13.2), and leukemia-free survival was 5 months (95% CI 3.4-7.3). Erlotinib was generally well tolerated, with modest single-agent activity. Given these results and preclinical data suggesting synergistic effect with azanucleosides, the combination should be further explored.

Phase 2 trial of CPX-351, a fixed 5:1 molar ratio of cytarabine/daunorubicin, vs cytarabine/daunorubicin in older adults with untreated AML

CPX-351 is a liposomal formulation of cytarabine:daunorubicin designed to deliver synergistic drug ratios to leukemia cells. In this phase 2 study, newly diagnosed older acute myeloid leukemia (AML) patients were randomized 2:1 to first-line CPX-351 or 7+3 treatment. The goal was to determine efficacy and identify patient subgroups that may benefit from CPX-351 treatment. Response rate (complete remission + incomplete remission) was the primary end point, with event-free survival (EFS) and overall survival (OS) as secondary end points. The 126 patients entered were balanced for disease and patient-specific risk factors. Overall, CPX-351 produced higher response rates (66.7% vs 51.2%, P = .07), meeting predefined criteria for success (P < .1). Differences in EFS and OS were not statistically significant. A planned analysis of the secondary AML subgroup demonstrated an improved response rate (57.6% vs 31.6%, P = .06), and prolongation of EFS (hazard ratio [HR] = 0.59, P = .08) and OS (HR = 0.46, P = .01). Recovery from cytopenias was slower after CPX-351 (median days to absolute neutrophil count ≥1000: 36 vs 32; platelets >100 000: 37 vs 28) with more grade 3-4 infections but without increase in infection-related deaths (3.5% vs 7.3%) or 60-day mortality (4.7% vs 14.6%), indicating acceptable safety. These results suggest a clinical benefit with CPX-351, particularly among patients with secondary AML, and provide the rationale for a phase 3 trial currently underway in newly diagnosed secondary AML patients. This study is registered at Clinicaltrials.gov as #NCT00788892.

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.

Beyond hypomethylating agents failure in patients with myelodysplastic syndromes

PURPOSE OF REVIEW

Although hypomethylating agents (HMAs) significantly improve outcomes in myelodysplastic syndromes (MDS), only half the patients achieve objective responses, and most responders lose response within 1-2 years. Azacitidine prolongs survival by a median of only 9.5 months. Failure of HMA therapy is associated with a very dismal prognosis. Therefore, novel therapeutic approaches are clearly needed.

RECENT FINDINGS

The sequential use of the alternative HMA after failure of first line HMA is associated with modest efficacy. The improved understanding of the biologic underpinnings of the disease have opened the door to study investigational agents that target disrupted molecular pathways critical to the pathogenesis of MDS. Combination treatment strategies using an azacitidine backbone are demonstrating promising early results. Expanding the applicability of allogeneic stem cell transplantation (alloSCT), the only curative modality, by reducing toxicity and relapse rates is another area of active research.

SUMMARY

Sequential switching to the alternative HMA, clinical trials of novel targeted therapies, azacitidine-based combination therapeutic strategies, and improvements in the alloSCT platform are the main directions in improving outcomes of MDS post HMA failure.

How we treat higher-risk myelodysplastic syndromes

Higher-risk myelodysplastic syndromes (MDS) are defined by patients who fall into higher-risk group categories in the original or revised International Prognostic Scoring System. Survival for these patients is dismal, and treatment should be initiated rapidly. Standard therapies include the hypomethylating agents azacitidine and decitabine, which should be administered for a minimum of 6 cycles, and continued for as long as a patient is responding. Once a drug fails in one of these patients, further treatment options are limited, median survival is <6 months, and consideration should be given to clinical trials. Higher-risk eligible patients should be offered consultation to discuss hematopoietic stem cell transplantation close to the time of diagnosis, depending on patient goals of therapy, with consideration given to proceeding to transplantation soon after an optimal donor is located. In the interim period before transplantation, hypomethylating agent therapy, induction chemotherapy, or enrollment in a clinical trial should be considered to prevent disease progression, although the optimal pretransplantation therapy is unknown.