Comparative clinical effectiveness of azacitidine versus decitabine in older patients with myelodysplastic syndromes

Clinical activity, pharmacokinetics, and pharmacodynamics of oral hypomethylating agents for myelodysplastic syndromes/neoplasms and acute myeloid leukemia: A multidisciplinary review

OBJECTIVE

To review the pharmacokinetic (PK)-pharmacodynamic (PD) profiles, disease setting, dosing, and safety of oral and parenteral hypomethylating agents (HMAs) for the treatment of myelodysplastic syndromes/neoplasms (MDS) and acute myeloid leukemia (AML), and to provide a multidisciplinary perspective on treatment selection and educational needs relating to HMA use.

DATA SOURCES

Clinical and real-world data for parenteral decitabine and azacitidine and two oral HMAs: decitabine-cedazuridine (DEC-C) for MDS and azacitidine (CC-486) for AML maintenance therapy.

DATA SUMMARY

Differences in the PK-PD profiles of oral and parenteral HMA formulations have implications for their potential toxicities and planned use. Oral DEC-C (decitabine 35 mg and cedazuridine 100 mg) has demonstrated equivalent systemic area under the concentration-time curve (AUC) exposure to a 5-day regimen of intravenous (IV) decitabine 20 mg/m2 and showed no significant difference in PD. The AUC equivalence of oral DEC-C and IV decitabine means that these regimens can be treated interchangeably (but must not be substituted within a cycle). Oral azacitidine has a distinct PK-PD profile versus IV or subcutaneous azacitidine, and the formulations are not bioequivalent or interchangeable owing to differences in plasma time-course kinetics and exposures. Clinical trials are ongoing to evaluate oral HMA combinations and novel oral HMAs, such as NTX-301 and ASTX030.

CONCLUSIONS

Treatment with oral HMAs has the potential to improve quality of life, treatment adherence, and disease outcomes versus parenteral HMAs. Better education of multidisciplinary teams on the factors affecting HMA treatment selection may help to improve treatment outcomes in patients with MDS or AML.

Treatment of Myelodysplastic Syndromes for Older Patients: Current State of Science, Challenges, and Opportunities

PURPOSE OF REVIEW

Myelodysplastic syndromes/neoplasms (MDS) represent a diverse group of pathologically distinct diseases with varying prognoses and risks of leukemia progression. This review aims to discuss current treatment options for elderly patients with MDS, focusing on patients ineligible for intensive chemotherapy or allogenic hematopoietic stem cell transplantation (HSCT). The challenges associated with treatment in this population and emerging therapeutic prospects are also explored.

RECENT FINDINGS

Recent advancements in molecular diagnostics have enhanced risk stratification by incorporating genetic mutations, notably through the molecular International Prognostic Scoring System (IPSS-M). Lower-risk MDS (LR-MDS) treatment ranges from observation to supportive measures and erythropoiesis-stimulating agents (ESAs), with emerging therapies like luspatercept showing promise. High-risk MDS (HR-MDS) is treated with hypomethylating agents (HMAs) or allogenic HSCT, but outcomes remain poor. Elderly MDS patients, often diagnosed after 70, pose challenges in treatment decision-making. The IPSS-M aids risk stratification, guiding therapeutic choices. For LR-MDS, supportive care, ESAs, and novel agents like luspatercept are considered. Treatment of HR-MDS involves HMAs or allogenic HSCT. Emerging treatments, including oral HMAs and novel agents targeting FLT3, and IDH 1/2 mutations, show promise. Future research should refine treatment strategies for this elderly population focusing on quality-of-life improvement.

Real-world study of the use of azacitidine in myelodysplasia in Australia

Hypomethylating agents are the most widely used upfront therapy for patients with myelodysplastic syndrome (MDS) who are not suitable for hematopoietic stem cell transplantation. In Australia, azacitidine was, until recently, the only approved and subsidized treatment for patients with intermediate-2 and high-risk MDS, chronic myelomonocytic leukemia, and low blast acute myeloid leukemia. We analyzed prescription data to evaluate the real-world persistence and overall survival (OS) of patients prescribed azacitidine for the first time in Australia. A retrospective cohort analysis of patients who had been prescribed Pharmaceutical Benefits Scheme (PBS)-listed azacitidine for the first time, between January 2016 and April 2021, was conducted using the PBS 10% dataset. Treatment persistence and OS were estimated using Kaplan-Meier methods. The impact of the number of treatment cycles and treatment adherence on OS was also estimated. There were 351 patients in the PBS 10% dataset who initiated treatment with azacitidine. The average age (standard deviation [SD]) at azacitidine initiation was 71.9 (11.1) years and the average number (SD) of azacitidine prescriptions was 5.6 (0.2). The median persistence on azacitidine was 15.6 months, and the OS was 13.4 months. The median OS for patients who had six or more cycles of azacitidine treatment was greater compared to patients who had five or less cycles of treatment. The data from this real-world study illustrate the unmet medical needs of patients with MDS treated with azacitidine in Australia. The majority of patients are not treated with the optimal number of cycles of azacitidine, which is negatively correlated with patient outcomes.

Clinical Outcomes in Patients With Refractory Anemia With Excess Blasts (RAEB) Who Receive Hypomethylating Agents (HMAs)

BACKGROUND

We sought to understand the clinical effectiveness associated with use of hypomethylating agents (HMAs) azacitidine (AZA) and decitabine (DEC) for patients with refractory anemia with excess blasts (RAEB; an established proxy for higher-risk myelodysplastic syndromes/neoplasms) in contemporary and representative real-world settings.

PATIENTS AND METHODS

We used the Surveillance, Epidemiology and End Results (SEER)-Medicare database, a linkage of cancer registry and Medicare claims data, to identify patients aged ≥ 66 years diagnosed with RAEB, between 2009 and 2017 in the United States, and who received AZA or DEC as first-line therapy. Outcomes measured were overall survival (OS), event-free survival (EFS), and incidence of progression-related acute myeloid leukemia (AML).

RESULTS

Of 973 eligible patients, 738 (75.8%) received AZA and 235 (24.2%) received DEC; 6.4% received hematopoietic cell transplantation during follow-up. In the overall population, median OS was 13.9 months (95% confidence interval [CI]: 12.9-15.0), median EFS was 5.2 months (95% CI: 4.9-5.7), and 38.0% of patients progressed to AML. Incidences of AML progression and death were 25.6% and 29.9%, respectively, at Year 1, and 34.3% and 44.8%, respectively, at Year 2. There were no significant differences in clinical benefits between AZA and DEC.

CONCLUSION

Median OS with both HMAs remained significantly shorter than in the AZA-001 clinical trial, highlighting how patient outcomes vary between clinical and real-world settings. Further research is required to understand why these disparities exist.

Real-world data of MDS and CMML in Japan: results of JALSG clinical observational study-11 (JALSG-CS-11)

We conducted a multicenter, prospective observational study of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), and chronic myelomonocytic leukemia (CMML) in Japan. From August 2011 to January 2016, we enrolled 6568 patients. Herein, we report the results for MDS (n = 2747) and CMML (n = 182). The percentage of patients aged 65 years or older was 79.5% for MDS and 79.7% for CMML. The estimated overall survival (OS) rate and cumulative incidence of AML evolution at 5 years were 32.3% (95% confidence interval: 30.2-34.5%) and 25.7% (23.9-27.6%) for MDS, and 15.0% (8.9-22.7%) and 39.4% (31.1-47.6%) for CMML. Both diseases were more common in men. The most common treatment for MDS was azacitidine, which was used in 45.4% of higher-risk and 12.7% of lower-risk MDS patients. The 5-year OS rate after treatment with azacitidine was 12.1% (9.5-15.1%) for of higher-risk MDS patients and 33.9% (25.6-42.4%) for lower-risk patients. The second most common treatment was erythropoiesis-stimulating agents, given to just 20% of lower-risk patients. This is the first paper presenting large-scale, Japanese data on survival and clinical characteristics in patients with MDS and CMML.

Full-Dose Azacitidine in 5 Days Versus 7 Days With a Weekend Break in Myelodysplastic Syndromes: A Retrospective Cohort Study

INTRODUCTION

Apart from transplantation, only azacitidine demonstrated a survival benefit in a phase III study in higher-risk myelodysplastic syndromes (MDS). The approved regimen is 75 mg/m2/day for 7 consecutive days, imposing a logistic challenge for outpatient weekend administration. Schedules with 5 days and 7 days with a weekend break (5 + 2) have been used for convenience despite the lack of strong scientific support. Most studies of alternative schedules were performed in lower-risk MDS and with dose reduction in the 5-day schedules.

METHODS

We performed a single-center, retrospective cohort study to compare full-dose azacitidine (7 × 75 mg/m2) administration in 5-day and 5 + 2-day schedules in a higher-risk MDS cohort. We evaluated 100 patients for overall survival and a subsample (49 patients) for acute myeloid leukemia-free survival (AMLFS), probability of infections and transfusion burden. Kaplan-Meier analysis and Cox models were used for survival analyses. Linear and logistic regressions were applied for univariate and multivariate assessment.

RESULTS

After a median follow-up of 10.8 months, patients treated with a 5-day schedule had a median overall survival of 12.5 months versus 15.0 months in the 5+2 group: HR 0.95 (95% CI, 0.57-1.56); P= .83. AMLFS was also similar between groups: HR 1.70 (95% CI, 0.70-4.14); P = .24. Azacitidine schedules were not predictive of infections nor number of red blood cell or platelet transfusions in multivariate analyses.

CONCLUSIONS

In higher-risk MDS, full-dose azacitidine (7 × 75 mg/m2) can be administered both in 5 days and in 7 days with a weekend break with no significant difference in survival, infection or transfusional outcomes.

A Personalized Risk Model for Azacitidine Outcome in Myelodysplastic Syndrome and Other Myeloid Neoplasms Identified by Machine Learning Model Utilizing Real-World Data

Azacitidine is an approved therapy for higher-risk myelodysplastic syndrome (MDS). However, only 30-40% patients respond to azacitidine, and the responses may take up to six cycles to become evident. Delayed responses and the myelosuppressive effects of azacitidine make it challenging to predict which patients will benefit. This is further compounded by a lack of uniform prognostic tools to identify patients at risk of early treatment failure. Hence, we performed a retrospective analysis of 273 consecutive azacytidine-treated patients. The median overall survival was 16.25 months with only 9% alive at 5 years. By using pre-treatment variables incorporated into a random forest machine learning model, we successfully identified those patients unlikely to benefit from azacytidine upfront (7.99 vs. 22.8 months, p < 0.0001). This model also identified those who required significantly more hospitalizations and transfusion support. Notably, it accurately predicted survival outcomes, outperforming the existing prognostic scoring system. By integrating somatic mutations, we further refined the model and identified three distinct risk groups with significant differences in survival (5.6 vs. 10.5 vs. 43.5 months, p < 0.0001). These real-world findings emphasize the urgent need for personalized prediction tools tailored to hypomethylating agents, reducing unnecessary complications and resource utilization in MDS treatment.

Considerations for Drug Development in Myelodysplastic Syndromes

Myelodysplastic syndromes (MDS) have historically been challenging diseases for drug development due to their biology, preclinical modeling, and the affected patient population. In April 2022, the FDA convened a panel of regulators and academic experts in MDS to discuss approaches to improve MDS drug development. The panel reviewed challenges in MDS clinical trial design and endpoints and outlined considerations for future trial design in MDS to facilitate drug development to meaningfully meet patient needs. Challenges for defining clinical benefit in patients with MDS include cumbersome response criteria, standardized transfusion thresholds, and application and validation of patient reported outcome instruments. Clinical trials should reflect the biology of disease evolution, the advanced age of patients with MDS, and how patients are treated in real-world settings to maximize the likelihood of identifying active drugs. In patients with lower-risk disease, response criteria for anemic patients should be based on baseline transfusion dependency, improvement in symptoms, and quality of life. For higher-risk patients with MDS, trials should include guidance to prevent dose reductions or delays that could limit efficacy, specify minimal durations of treatment (in the absence of toxicity or progression), and have endpoints focused on overall survival and durable responses. MDS trials should be designed from the outset to allow the practicable application of new therapies in this high-needs population, with drugs that can be administered and tolerated in community settings, and with endpoints that meaningfully improve patients' lives over existing therapies.

Magrolimab in Combination With Azacitidine in Patients With Higher-Risk Myelodysplastic Syndromes: Final Results of a Phase Ib Study

PURPOSE

Magrolimab is a monoclonal antibody that blocks cluster of differentiation 47, a don't-eat-me signal overexpressed on cancer cells. Cluster of differentiation 47 blockade by magrolimab promotes macrophage-mediated phagocytosis of tumor cells and is synergistic with azacitidine, which increases expression of eat-me signals. We report final phase Ib data in patients with untreated higher-risk myelodysplastic syndromes (MDS) treated with magrolimab and azacitidine (ClinicalTrials.gov identifier: NCT03248479).

PATIENTS AND METHODS

Patients with previously untreated Revised International Prognostic Scoring System intermediate-/high-/very high-risk MDS received magrolimab intravenously as a priming dose (1 mg/kg) followed by ramp-up to a 30 mg/kg once-weekly or once-every-2-week maintenance dose. Azacitidine 75 mg/m2 was administered intravenously/subcutaneously once daily on days 1-7 of each 28-day cycle. Primary end points were safety/tolerability and complete remission (CR) rate.

RESULTS

Ninety-five patients were treated. Revised International Prognostic Scoring System risk was intermediate/high/very high in 27%, 52%, and 21%, respectively. Fifty-nine (62%) had poor-risk cytogenetics and 25 (26%) had TP53 mutation. The most common treatment-emergent adverse effects included constipation (68%), thrombocytopenia (55%), and anemia (52%). Median hemoglobin change from baseline to first postdose assessment was -0.7 g/dL (range, -3.1 to +2.4). CR rate and overall response rate were 33% and 75%, respectively. Median time to response, duration of CR, duration of overall response, and progression-free survival were 1.9, 11.1, 9.8, and 11.6 months, respectively. Median overall survival (OS) was not reached with 17.1-month follow-up. In TP53-mutant patients, 40% achieved CR with median OS of 16.3 months. Thirty-four patients (36%) had allogeneic stem-cell transplant with 77% 2-year OS.

CONCLUSION

Magrolimab + azacitidine was well tolerated with promising efficacy in patients with untreated higher-risk MDS, including those with TP53 mutations. A phase III trial of magrolimab/placebo + azacitidine is ongoing (ClinicalTrials.gov identifier: NCT04313881 [ENHANCE]).

Evolution of Therapeutic Benefit Measurement Criteria in Myelodysplastic Syndromes/Neoplasms

ABSTRACT

Myelodysplastic syndromes/neoplasms (MDS) are heterogeneous, clonal myeloid neoplasms characterized by ineffective hematopoiesis, progressive cytopenias, and an increased risk of progression to acute myeloid leukemia. The diversity in disease severity, morphology, and genetic landscape challenges not only novel drug development but also therapeutic response assessment. The MDS International Working Group (IWG) response criteria were first published in the year 2000 focusing on measures of blast burden reduction and hematologic recovery. Despite revision of the IWG criteria in 2006, correlation between IWG-defined responses and patient-focused outcomes, including long-term benefits, remains limited and has potentially contributed to failures of several phase III clinical trials. Several IWG 2006 criteria also lacked clear definitions leading to problems in practical applications and interobserver and intraobserver consistency of response reporting. Although the 2018 revision addressed lower-risk MDS, the most recent update in 2023 redefined responses for higher-risk MDS and has set out to provide clear definitions to enhance consistency while focusing on clinically meaningful outcomes and patient-centered responses. In this review, we analyze the evolution of the MDS response criteria, limitations, and areas of improvement.

What's Next after Hypomethylating Agents Failure in Myeloid Neoplasms? A Rational Approach

Hypomethylating agents (HMA) such as azacitidine and decitabine are a mainstay in the current management of patients with myelodysplastic syndromes/neoplasms (MDS) and acute myeloid leukemia (AML) as either single agents or in multidrug combinations. Resistance to HMA is not uncommon, and it can result due to several tumor cellular adaptations. Several clinical and genomic factors have been identified as predictors of HMA resistance. However, the management of MDS/AML patients after the failure of HMA remains challenging in the absence of standardized guidelines. Indeed, this is an area of active research with several potential therapeutic agents currently under development, some of which have demonstrated therapeutic potential in early clinical trials, especially in cases with particular mutational characteristics. Here, we review the latest findings and give a rational approach for such a challenging scenario.

Advances in myelodysplastic syndromes: promising novel agents and combination strategies

INTRODUCTION

Myelodysplastic syndromes (MDS) are heterogeneous group of clonal hematopoietic stem cell neoplasms that have limited approved treatment options. Multiple novel agents are currently being tested in a clinical trial setting. From a therapeutic perspective, MDS is generally divided into lower-risk and higher-risk disease. In this review, we summarize some of the most prominent novel agents currently in development.

AREAS COVERED

This review focuses on select clinical trials in both lower- and higher-risk MDS, elucidating the mechanisms of action and rationale for drug combinations and summarizing early safety and efficacy data using novel agents in MDS.

EXPERT OPINION

Advances in understanding the innate immune system, telomere biology, as well as genomic drivers of the disease have led to the development of multiple novel agents that are currently in late stages of clinical development in MDS. Imetelstat is being tested in lower-risk disease and the phase III clinical trial recently completed accrual. Magrolimab, sabatolimab, and venetoclax in addition to novel oral hypomethylating agents (HMA) are being investigated in higher-risk MDS. These advances will hopefully bring better treatment options to patients and lead to a shift in the treatment paradigm. Post HMA therapy remains an area of dire unmet need.

How I Manage Transplant Ineligible Patients with Myelodysplastic Neoplasms

Myelodysplastic neoplasms, formerly known as myelodysplastic syndromes (MDS), represent a group of clonal disorders characterized by a high degree of clinical and molecular heterogeneity, and an invariable tendency to progress to acute myeloid leukemia. MDS typically present in the elderly with cytopenias of different degrees and bone marrow dysplasia, the hallmarks of the disease. Allogeneic hematopoietic stem cell transplant is the sole curative approach to date. Nonetheless, given the disease’s demographics, only a minority of patients can benefit from this procedure. Currently used prognostic schemes such as the Revised International Prognostic Scoring System (R-IPSS), and most recently the molecular IPSS (IPSS-M), guide clinical management by dividing MDS into two big categories: lower- and higher-risk cases, based on a cut-off score of 3.5. The main clinical problem of the lower-risk group is represented by the management of cytopenias, whereas the prevention of secondary leukemia progression is the goal for the latter. Herein, we discuss the non-transplant treatment of MDS, focusing on current practice and available therapeutic options, while also presenting new investigational agents potentially entering the MDS therapeutic arsenal in the near future.

Impact of Hypomethylating Agent Use on Hospital and Emergency Room Visits, and Predictors of Early Discontinuation in Patients With Higher-Risk Myelodysplastic Syndromes

BACKGROUND

Previous analyses using the SEER-Medicare database have reported substantial underutilization of hypomethylating agents (HMAs) among patients with higher-risk myelodysplastic syndromes (MDS), and an association between poor HMA persistence and high economic burden. We aimed to compare rates of hospitalizations and emergency room (ER) visits among patients with higher-risk MDS according to use or non-use of HMA therapy, and to explore factors associated with early discontinuation of HMA therapy.

PATIENTS AND METHODS

We used the 2010-2016 SEER-Medicare database to identify patients aged ≥66 years with a new diagnosis of refractory anemia with excess blasts (RAEB; a surrogate for higher-risk MDS) between 2011 and 2015. New hospitalizations and ER visits during the 12 months following MDS diagnosis were determined. Treatment discontinuation was defined as stopping HMA therapy before 4 cycles.

RESULTS

Overall, 664 (55.8%) patients were HMA users and 526 (44.2%) non-users. Non-users had more hospitalizations (mean 0.47 vs. 0.30, P < .001) and ER visits (mean 0.69 vs. 0.41, P = .005) per month than HMA users. Among HMA users, 193 (29.1%) discontinued HMA therapy before 4 cycles, and 91 (47.2%) of these after 1 cycle. Older age and poor performance status were associated with higher risk of HMA discontinuation.

CONCLUSION

An increased rate of hospitalizations and ER visits occurred in HMA non-users vs. HMA users. Approximately one-third of patients discontinued HMA therapy early. Predictors of discontinuation included older age and poor performance status. Novel approaches are needed to improve utilization and persistence with HMA therapy and associated outcomes, particularly among these higher-risk groups.

Treatment of myelodysplastic syndromes in the era of precision medicine and immunomodulatory drugs: a focus on higher-risk disease

Myelodysplastic syndromes (MDS) are a heterogeneous clonal disease of myeloid neoplasms characterized by ineffective hematopoiesis, variable degree of cytopenias, and an increased risk of progression to acute myeloid leukemia (AML). Molecular and genetic characterization of MDS has led to a better understanding of the disease pathophysiology and is leading to the development of novel therapies. Targeted and immune therapies have shown promising results in different hematologic malignancies. However, their potential use in MDS is yet to be fully defined. Here, we review the most recent advances in therapeutic approaches in MDS, focusing on higher-risk disease. Allogeneic hematopoietic cell transplantation is beyond the scope of this article.

Pevonedistat plus azacitidine vs azacitidine alone in higher-risk MDS/chronic myelomonocytic leukemia or low-blast percentage AML

PANTHER was a global, randomized phase 3 trial of pevonedistat plus azacitidine (n = 227) vs azacitidine monotherapy (n = 227) in patients with newly diagnosed higher-risk myelodysplastic syndromes (MDS) (n = 324), higher-risk chronic myelomonocytic leukemia (n = 27), or acute myeloid leukemia (AML) with 20-30% blasts (n = 103). The primary endpoint was event-free survival (EFS). In the intent-to-treat (ITT) population median EFS was 17.7 months with pevonedistat plus azacitidine vs 15.7 months with azacitidine (hazard ratio [HR], 0.968 [95% confidence interval (CI), 0.757-1.238], P = 0.557) and in the higher-risk MDS cohort median EFS was 19.2 vs 15.6 months (HR, 0.887 [95% CI, 0.659-1.193, P = 0.431). Median overall survival (OS) in the higher-risk MDS cohort was 21.6 vs 17.5 months (HR, 0.785, P = 0.092]), and in patients with AML with 20-30% blasts was 14.5 vs 14.7 months (HR, 1.107, P = 0.664). In a post-hoc analysis, median OS in the higher-risk MDS cohort for patients receiving >3 cycles was 23.8 vs 20.6 months (P = 0.021) and for >6 cycles was 27.1 vs 22.5 months (P = 0.008). No new safety signals were identified, and azacitidine dose intensity was maintained. Common hematologic grade ≥3 treatment emergent adverse events were anemia (33% vs 34%), neutropenia (31% vs 33%), and thrombocytopenia (30% vs 30%). These results underscore the importance of large, randomized controlled trials in these heterogeneous myeloid diseases and the value of remaining on therapy >3 cycles. (ClinicalTrials.gov, NCT03268954).

Impact of infectious comorbidity and overall time of hospitalization in total outpatient management of acute myeloid leukemia patients following venetoclax and hypomethylating agents

Venetoclax (VEN) and hypomethylating agent (HMAs) regimens are emerging as the standard of care for unfit for chemotherapy acute myeloid leukemia (AML) patients, but the safety and feasibility of a total outpatient management have not been fully investigated. Fifty‐nine AML patients with active disease received VEN and HMAs. Nineteen out of 59 (32.2%) patients received the first cycle as inpatients, whereas 40/59 (67.8%) patients were treated in the outpatient setting. No significant differences were observed with regard to incidence of adverse events (AEs), including tumor lysis syndrome (TLS), and the 30‐day and 60‐day mortality was comparable. Notably, an infectious prophylaxis inspired to that adopted during intensive chemotherapy resulted in a low infection rate with a reduced bacterial infections incidence in out‐ versus hospitalized patients (p < .0001). The overall time of hospitalization was significantly shorter in patients who received a total outpatient treatment as compared to those who received the first cycle as inpatients (5.9 vs. 39.7 days, p < .0001). Despite the adopted differences in treatment management, the efficacy was similar. These data indicate that a total outpatient management of VEN and HMAs is feasible in AML patients without negatively impacting on treatment efficacy and may yield pharmacoeconomic and quality‐of‐life benefits.

Azacitidine vs. Decitabine in Unfit Newly Diagnosed Acute Myeloid Leukemia Patients: Results from the PETHEMA Registry

The hypomethylating agents, decitabine (DEC) and azacitidine (AZA), allowed more elderly acute myeloid leukemia (AML) patients to be treated. However, there are little direct comparative data on AZA and DEC. This multicenter retrospective study compared the outcomes of AZA and DEC in terms of response and overall survival (OS). Potential predictors associated with response and OS were also evaluated. A total of 626 AML patients were included (487 treated with AZA and 139 with DEC). Response rates were similar in both groups: CR was 18% with AZA vs. 23% with DEC (p = 0.20), CR/CRi was 20.5% vs. 25% (p = 0.27) and ORR was 32% vs. 39.5% (p = 0.12), respectively. Patients with leukocytes < 10 × 109/L, bone marrow blasts < 50% and ECOG ≥ 2 had higher ORR with DEC than with AZA. OS was similar in both groups: 10.4 months (95% CI: 9.2−11.7) vs. 8.8 months (95% CI: 6.7−11.0, p = 0.455), for AZA and DEC, respectively. Age (≥80 years), leukocytes (≥ 10 × 109/L), platelet count (<20 × 109/L) and eGFR (≥45 mL/min/1.73 m2) were associated with higher OS with AZA compared to DEC. In conclusion, we found no differences in response and OS rates in AML patients treated with AZA or DEC.

The Contrasting Delayed Effects of Transient Exposure of Colorectal Cancer Cells to Decitabine or Azacitidine

Simple Summary

Decitabine and azacitidine are cytosine analogs representing the class of drugs interfering with DNA methylation. Due to their molecular homology and similar clinical application these drugs are viewed as interchangeable. Despite their unique epigenetic mechanism of action, the studies of the prolonged activity of decitabine and azacitidine are rare. Our head-to-head comparison revealed profound differences in the activities of decitabine and azacitidine important in their anti-cancer potential and clinical application. We show that azacitidine, despite significant immediate toxicity, has negligible long-term effects. Contrary, decitabine, which does not exert initial toxicity, profoundly worsened the condition of the cancer cells over time. The effects of decitabine need a relatively long time to develop. This property is crucial for the proper design of studies or therapy involving decitabine. It undermines opinion about the similar therapeutic mechanism and interchangeability of decitabine and azacitidine.

Abstract

(1) Background: Decitabine and azacitidine are cytosine analogues representing the class of drugs interfering with DNA methylation. Due to their molecular homology and similar clinical application, both drugs are often regarded as interchangeable. Despite their unique mechanism of action the studies designed for observation and comparison of the prolonged activity of these drugs are rare. (2) Methods: The short-time (20–72 h) and long-term (up to 20 days) anti-cancer activity of decitabine and azacitidine has been studied in colorectal cancer cells. We observe the impact on cell culture’s viability, clonogenicity, proliferation, and expression of CDKN1A, CCND1, MDM2, MYC, CDKN2A, GLB1 genes, and activity of SA-β-galactosidase. (3) Results: Decitabine has much stronger anti-clonogenic activity than azacitidine. We show that azacitidine, despite significant immediate toxicity, has negligible long-term effects. Contrary, decitabine, which does not exert initial toxicity, profoundly worsened the condition of the cells over time. On the 13th day after treatment, the viability of cells was decreased and proliferation inhibited. These functional changes were accompanied by up-regulation of expression CDKN1A, CCND1, and CDKN2A genes and increased activation of SA-β-galactosidase, indicating cellular senescence. (4) Conclusions: Our head-to-head comparison revealed profound differences in the activities of decitabine and azacitidine important in their anti-cancer potential and clinical application. The effects of decitabine need relatively long time to develop. This property is crucial for proper design of studies and therapy concerning decitabine and undermines opinion about the similar therapeutic mechanism and interchangeability of these drugs.

Differential Histone Posttranslational Modifications Induced by DNA Hypomethylating Agents

Introduction

The prototype DNA hypomethylating agents 5-azacytidine (5AC) and decitabine (DAC) are currently FDA-approved for treatment of blood and bone marrow disorders like myelodysplastic syndrome. 5AC and DAC are considered similar drugs and were shown to induce histone modifications that modulate gene expression. The aim of this study is to compare the effect of both drugs on histone acetylation and methylation at multiple histone amino acids residues.

Methods

Mass spectrometry was used to compare the effect of both drugs on 95 different histone posttranslational modifications (PTMs) in leukemia cells. ChIP-Seq analysis was used to compare the impact of both drugs on the genome-wide acetylation of the H3K9 mark using primary leukemia cells from six de-identified AML patients.

Results

Both DAC and 5AC induced histone PTMs in different histone isoforms like H1.4, H2A, H3, H3.1, and H4. Changes in both histone methylation and acetylation were observed with both drugs; however, there were distinct differences in the histone modifications induced by the two drugs. Since both drugs were shown to increase the activity of the HDAC SIRT6 previously, we tested the effect of 5AC on the acetylation of H3K9, the physiological substrate SIRT6, using ChIP-Seq analysis and compared it to the previously published DAC-induced changes. Significant H3K9 acetylation changes (P< .05) were detected at 925 genes after 5AC treatment vs only 182 genes after DAC treatment. Nevertheless, the gene set modified by 5AC was different from that modified by DAC with only ten similar genes modulated by both drugs.

Conclusion

Despite similarity in chemical structure and DNA hypomethylating activity, 5AC and DAC induced widely different histone PTMs and considering them interchangeable should be carefully evaluated. The mechanism of these histone PTM changes is not clear and may involve modulation of the activity or the expression of the enzymes inducing histone PTMs.

A Randomized Phase 2 Trial of Azacitidine ± Durvalumab as First-line Therapy for Higher-Risk Myelodysplastic Syndromes

This is the first reported randomized trial of immune checkpoint inhibitor therapy in HR-MDS.

Azacitidine combined with the PD-L1 inhibitor durvalumab was feasible but did not improve outcomes over azacitidine alone.

Azacitidine-mediated hypomethylation promotes tumor cell immune recognition but may increase the expression of inhibitory immune checkpoint molecules. We conducted the first randomized phase 2 study of azacitidine plus the immune checkpoint inhibitor durvalumab vs azacitidine monotherapy as first-line treatment for higher-risk myelodysplastic syndromes (HR-MDS). In all, 84 patients received 75 mg/m² subcutaneous azacitidine (days 1-7 every 4 weeks) combined with 1500 mg intravenous durvalumab on day 1 every 4 weeks (Arm A) for at least 6 cycles or 75 mg/m² subcutaneous azacitidine alone (days 1-7 every 4 weeks) for at least 6 cycles (Arm B). After a median follow-up of 15.25 months, 8 patients in Arm A and 6 in Arm B remained on treatment. Patients in Arm A received a median of 7.9 treatment cycles and those in Arm B received a median of 7.0 treatment cycles with 73.7% and 65.9%, respectively, completing ≥4 cycles. The overall response rate (primary end point) was 61.9% in Arm A (26 of 42) and 47.6% in Arm B (20 of 42; P = .18), and median overall survival was 11.6 months (95% confidence interval, 9.5 months to not evaluable) vs 16.7 months (95% confidence interval, 9.8-23.5 months; P = .74). Durvalumab-related adverse events (AEs) were reported by 71.1% of patients; azacitidine-related AEs were reported by 82% (Arm A) and 81% (Arm B). Grade 3 or 4 hematologic AEs were reported in 89.5% (Arm A) vs 68.3% (Arm B) of patients. Patients with TP53 mutations tended to have a worse response than patients without these mutations. Azacitidine increased programmed cell death ligand 1 (PD-L1 [CD274]) surface expression on bone marrow granulocytes and monocytes, but not blasts, in both arms. In summary, combining azacitidine with durvalumab in patients with HR-MDS was feasible but with more toxicities and without significant improvement in clinical outcomes over azacitidine alone. This trial was registered at www.clinicaltrials.gov as #NCT02775903.

Management of the Older Patient with Myelodysplastic Syndrome

No two diagnoses of myelodysplastic syndrome are genuinely alike, owing to differing and dynamic mutational topography and epigenetic aberrancy. Consequently, no two patients with myelodysplastic syndrome are identical and disease-specific and patient-specific factors are considered in formulating the optimal treatment, which includes few that are disease modifying. Age itself should not be an absolute contraindication to therapy, including intensive therapy such as allogeneic hematopoietic stem cell transplantation, which is the only curative therapy. However, age associates with an increased prevalence of frailty and comorbidities that must be considered and may preclude a path to cure. Palliative therapies are the mainstay for many patients with myelodysplastic syndrome, which is a disease of older adults with the majority of patients diagnosed at age ≥ 75 years. The older patient requires heightened attention to end organ function/reserve and drug-drug interactions as well as insurance, income, cost, and socioeconomic and psychosocial issues that influence management. Many prior studies have included relatively younger populations or have not specifically performed high-quality subgroup analyses of older patients. In this review, we discuss the available standard-of-care therapies for myelodysplastic syndrome as they specifically relate to the older population and assess the emerging therapeutics that may further the pursuit for personalized treatment and improve both the outcomes and quality of life of the older patient with myelodysplastic syndrome.

Clinical outcomes of older patients with AML receiving hypomethylating agents: a large population-based study in the United States

The hypomethylating agents (HMAs) azacitidine and decitabine have been the de facto standard of care for patients with acute myeloid leukemia (AML) who are unfit for intensive therapy. Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we identified 2263 older adults (age ≥66 years) diagnosed with AML during 2005-2015 who received a first-line HMA; 1154 (51%) received azacitidine, and 1109 (49%) received decitabine. Median survival from diagnosis was 7.1 and 8.2 months (P < .01) for azacitidine- and decitabine-treated patients, respectively. Mortality risk was higher with azacitidine vs decitabine (hazard ratio [HR], 1.11; 95% confidence interval [CI], 1.01-1.21; P = .02). The findings were similar when evaluating only patients completing ≥4 cycles (42% of patients treated with either azacitidine or decitabine). These findings lost significance when evaluating those completing a standard 7-day schedule of azacitidine (34%) vs 5-day schedule for decitabine (66%) (HR, 0.95; 95% CI, 0.83-1.08; P = .43). Red blood cell (RBC) transfusion independence (TI) was achieved in one-third of patients with no difference between the 2 HMAs. In conclusion, the majority of older AML patients did not receive the minimum of 4 cycles of HMA often needed to elicit clinical benefit. We observed no clinically meaningful differences between azacitidine- and decitabine-treated patients in their achievement of RBC TI or survival.

Cedazuridine/decitabine: from preclinical to clinical development in myeloid malignancies

Since the US Food and Drug Administration (FDA) approvals of parenteral decitabine and azacitidine, DNA methyltransferase inhibitors, otherwise referred to as DNA hypomethylating agents (HMAs), have been a mainstay in the treatment of higher-risk myelodysplastic syndromes. The development of oral HMAs has been an area of active interest; however, oral bioavailability has been quite poor due to rapid metabolism by cytidine deaminase (CDA). This led to the development of the novel CDA inhibitor cedazuridine, which was combined with an oral formulation of decitabine. Preclinical work demonstrated a pharmacokinetic and pharmacodynamic profile approximate to parenteral decitabine, leading to early-phase clinical trials of oral cedazuridine-decitabine (C-DEC) in myelodysplastic syndromes and chronic myelomonocytic leukemia (CMML). A combination of oral decitabine 35 mg with oral cedazuridine 100 mg was established as the recommended phase 2 dose. Phase 2 data confirmed bioequivalence of C-DEC when compared with parenteral decitabine, and a larger phase 3 trial has demonstrated similar results, leading to the FDA approval of C-DEC for use in intermediate/high-risk myelodysplastic syndrome (MDS) and CMML. This review will focus upon the current role of HMA therapy in MDS/CMML, preclinical and clinical development of C-DEC, and potential roles of oral HMA therapy in myeloid malignancies moving forward.

Navigating Myelodysplastic and Myelodysplastic/Myeloproliferative Overlap Syndromes

Myelodysplastic syndromes (MDS) and MDS/myeloproliferative neoplasms (MPNs) are clonal diseases that differ in morphologic diagnostic criteria but share some common disease phenotypes that include cytopenias, propensity to acute myeloid leukemia evolution, and a substantially shortened patient survival. MDS/MPNs share many clinical and molecular features with MDS, including frequent mutations involving epigenetic modifier and/or spliceosome genes. Although the current 2016 World Health Organization classification incorporates some genetic features in its diagnostic criteria for MDS and MDS/MPNs, recent accumulation of data has underscored the importance of the mutation profiles on both disease classification and prognosis. Machine-learning algorithms have identified distinct molecular genetic signatures that help refine prognosis and notable associations of these genetic signatures with morphologic and clinical features. Combined geno-clinical models that incorporate mutation data seem to surpass the current prognostic schemes. Future MDS classification and prognostication schema will be based on the portfolio of genetic aberrations and traditional features, such as blast count and clinical factors. Arriving at these systems will require studies on large patient cohorts that incorporate advanced computational analysis. The current treatment algorithm in MDS is based on patient risk as derived from existing prognostic and disease classes. Luspatercept is newly approved for patients with MDS and ring sideroblasts who are transfusion dependent after erythropoietic-stimulating agent failure. Other agents that address red blood cell transfusion dependence in patients with lower-risk MDS and the failure of hypomethylating agents in higher-risk disease are in advanced testing. Finally, a plethora of novel targeted agents and immune checkpoint inhibitors are being evaluated in combination with a hypomethylating agent backbone to augment the depth and duration of response and, we hope, improve overall survival.

Treatment patterns and outcomes in patients with myelodysplastic syndromes treated with hypomethylating agents: a SEER-Medicare analysis

To describe real-world treatment patterns and outcomes among adult patients with myelodysplastic syndromes (MDS) treated with hypomethylating agents (HMA), patients were identified in the SEER-Medicare database (01/2006-12/2016); 3,046 patients with MDS treated with HMA were included. An algorithm was developed to categorize patients into MDS risk groups: the majority of patients were classified as Higher-risk (70.9%), 8.0% as Intermediate-risk, and 21.1% as Unknown-risk. Overall, 77.4% of patients initiated azacitidine and 22.6% decitabine; they received an average of 5.1 index-HMA cycles, of which 90.9% were complete with a median cycle duration of 28 days. Median survival was 11.6, 18.4, and 19.1 months for the Higher-risk, Intermediate-risk, and Unknown-risk groups, respectively. Median time-to-AML transformation was 19.3 months for the Higher-risk group and 50.4 months for the Intermediate-risk group (not reached for Unknown-risk). Data highlight the unmet medical needs of patients with MDS treated with HMA, particularly for the Higher-risk MDS group.

Direct Medical Costs Associated With Treatment Nonpersistence in Patients With Higher-Risk Myelodysplastic Syndromes Receiving Hypomethylating Agents: A Large Retrospective Cohort Analysis

BACKGROUND

Suboptimal use of hypomethylating agents (HMAs) among higher-risk myelodysplastic syndrome (HR-MDS) patients can translate into worse health outcomes and economic burden. We estimated the direct medical costs associated with HMA treatment nonpersistence among HR-MDS patients.

PATIENTS AND METHODS

Using the Surveillance, Epidemiology, and End Results-Medicare linked database, a retrospective cohort of patients diagnosed with refractory anemia with excess blasts (RAEB), a diagnosis that substantially overlaps with HR-MDS, between January 2011 and December 2015 was analyzed. Patients who had ≥ 1 year of continuous Medicare enrollment before diagnosis and who did not receive stem cell transplant or lenalidomide in the follow-up period were included. Patients receiving HMAs were stratified into HMA persistent (≥4 HMA cycles) and HMA nonpersistent (<4 cycles or a gap of ≥ 90 days between cycles) groups. Healthcare resource use and costs during the follow-up period were reported descriptively as total and per patient per month (PPPM). Weighted generalized linear models (GLM) were used to compare estimated healthcare resource use and costs between HMA groups.

RESULTS

Among the 664 patients with RAEB, 295 (44.4%) were HMA nonpersistent and 369 (55.6%) HMA persistent. On the basis of weighted GLM analysis, the HMA nonpersistent group incurred significantly (P < .05) higher total PPPM costs compared to the HMA persistent group ($18,039 vs. $13,893), particularly for hospitalization ($3,375 vs. $2,131), and emergency room ($5,517 vs. $2,867) costs.

CONCLUSION

There is a substantial economic burden associated with early discontinuation of guideline-recommended HMA therapy in RAEB patients. The study findings necessitate closer care management in this population in order to improve outcomes and reduce healthcare spending.

Healthcare resource utilization and costs in patients with myelodysplastic syndromes treated with hypomethylating agents: a SEER-Medicare analysis

AIMS

To describe healthcare resource utilization (HRU) and costs in patients with myelodysplastic syndromes (MDS) treated with hypomethylating agents (HMA) based on HMA-treatment response.

MATERIALS AND METHODS

SEER-Medicare data (January 2006-December 2016) were used to identify adults diagnosed with MDS (SEER: January 2009-December 2015) initiated on HMA (index date). HMA-treatment success (indicators: ≥7 HMA cycles, stem cell transplantation, and transfusion independence) or failure (indicators: acute myeloid leukemia [AML], AML-like treatment, and death) was determined using a claim-based algorithm. HRU and costs were assessed from the index date to 1-year post-index, overall and stratified by HMA-treatment success or failure. Among patients with HMA-treatment failure, HRU and costs were also assessed from failure to 1-year post-failure.

RESULTS

The study included 3,046 patients (mean age: 77.4 years; females: 36.8%). Rates of HMA-treatment success and failure were 44.4% and 76.2%, respectively (20.6% had HMA-treatment success then failure). Overall, patients had 15.2 inpatient admissions per-100-patients-per-month (median follow-up: 5.9 months). Patients with HMA-treatment success had 7.5 inpatient admissions per-100-patients-per-month (median follow-up: 12.0 months), while those with HMA-treatment failure had 20.4 and 35.3 admissions per-100-patients-per-month pre- and post-HMA-treatment failure, respectively (median follow-up: 4.3 and 1.8 months, pre- and post-HMA-treatment failure, respectively). Mean total healthcare costs were $12,494 per-patient-per-month overall, $8,069 per-patient-per-month among patients with HMA-treatment success, and $13,809 and $19,242 per-patient-per-month pre- and post-HMA-treatment failure, respectively. Outpatient costs (68.3%) were the main contributor of total healthcare costs overall, while inpatient costs (80.3%) were the main cost driver post-HMA-treatment failure.

LIMITATIONS

Without available laboratory test results, clinical indicators observed in claims were used to assess HMA-treatment response.

CONCLUSIONS

Over 75% of patients with MDS failed HMA-treatment within 6 months of initiation and were observed with more inpatient admissions than those with HMA-treatment success, translating into substantially higher healthcare costs. HMA-treatment failure results in an important economic burden in MDS patients.

Under-use of Hypomethylating Agents in Patients With Higher-risk Myelodysplastic Syndrome in the United States: A Large Population-based Analysis

BACKGROUND

Recent data suggest significant underutilization of hypomethylating agents (HMAs) that are recommended treatments for patients with myelodysplastic syndromes (MDS) with refractory anemia with excess blasts (RAEB). The study objective was to assess the degree of HMA use and predictors of HMA underuse in this population.

PATIENTS AND METHODS

This was a retrospective study including patients diagnosed with the RAEB form of MDS between January 2011 and December 2015 using the Surveillance, Epidemiology, and End Results-Medicare linked database. Patients were excluded if they had < 1 year of continuous enrollment before diagnosis or received stem cell transplant or lenalidomide during the follow-up period. HMA non-peristence was defined as use of < 4 cycles (3-10 HMA days/28 days) of HMAs or a gap of ≥ 90 days between consecutive cycles. Patients were characterized as HMA never-users, HMA-persistent users, and HMA-non-persistent users. Descriptive statistics were used to summarize patient characteristics. Multivariable logistic regression was used to assess predictors of HMA underuse and persistence.

RESULTS

Of the 1190 patients, 526 (44%) were never-users, 295 (25%) were non-persistent users, and 369 (31%) were persistent users. Age at diagnosis (eg, 66-70 years vs. ≥ 80 years; odds ratio [OR], 2.36; 95% confidence interval [CI], 1.56-3.56), marital status (single vs. married; OR, 0.67; 95% CI, 0.51-0.89), National Cancer Institute comorbidity index (≥ 3 vs. 0-1; OR, 0.62; 95% CI, 0.46-0.83), and performance status (poor vs. good; OR, 0.67; 95% CI, 0.51-0.87) were significantly associated with HMA underuse.

CONCLUSION

Several demographic and clinical factors were associated with underuse of HMAs. There is need for a better understanding of suboptimal HMA use and its relationship with clinical response.

Hypomethylating agent (HMA) therapy use and survival in older adults with Refractory Anemia with Excess Blasts (RAEB) in the United States (USA): a large propensity score-matched population-based study†

Hypomethylating agents (HMA) showed overall survival (OS) benefits in patients with higher-risk myelodysplastic syndromes (HR-MDS) in clinical trials. We conducted a retrospective cohort study of Surveillance, Epidemiology, and End Results (SEER)-Medicare data of patients ≥66 years diagnosed with refractory anemia with excess blasts (RAEB), a proxy for HR-MDS, in 01/2001-04/2004 (pre-period) or 01/2006-12/2011 (post-period). Association between post-period diagnosis and OS was examined using propensity scores (PS)-matched samples. Among 1876 RAEB patients, median OS was 9 months and 30.8% received HMAs (3.6% in pre-period; 43.0% in post-period) with no association between post-period diagnosis and OS. In the top PS quartile, post-period diagnosis was associated with a 74% lower risk of death (Hazard ratio [HR] = 0.26, 95%-CI: 0.10-0.69, p = 0.007), while outcomes were worse in the lowest PS quartile (HR = 2.80, 95%-CI: 1.06-7.36, p = 0.037). HMA lead to a 3-month OS benefit for patients most likely to receive HMA but not for unselected RAEB cohort.

Hypomethylating agent based combinations in higher risk myelodysplastic syndrome

For over a decade the hypomethylating agents (HMA) azacitidine and decitabine have been the mainstay of therapy for myelodysplastic syndrome (MDS). There is a critical need to improve frontline therapy, given that only up to half of high-risk MDS patients will respond to HMA therapy, and responses are short-lived. Currently, a key strategy has been to combine HMAs with other novel agents to improve patient outcomes. While synergy of agents is the goal of combination therapy, combinations often come at the cost of increased side effects that are often intolerable in this vulnerable population. The purpose of this review is to critically examine clinically relevant HMA combinations and discuss the future of MDS management.

Therapeutic strategies in low and high-risk MDS: What does the future have to offer?

Myelodysplastic syndromes (MDS) are a heterogeneous group of myeloid disorders characterized by cytopenias and increased risk of acute leukemia transformation. Prognosis of MDS patients can be assessed by various scoring systems, the most common being the International Prognostic Scoring System (IPSS) now refined by the revised version (IPSS-R). Genomic information at baseline, that is currently not included in clinical prognostic scores, will, in the future, help us to stratify patients with various prognoses. Therapy of MDS is based on risk stratification. The aim of therapy in low-risk MDS is to improve anemia or thrombocytopenia, decrease transfusion needs, improve quality of life, attempt to prolong overall survival, and reduce the risk of progression. In higher-risk MDS, the goal of therapy is to prolong survival and reduce the risk of transformation into acute leukemia. Only a few drugs are currently available for treatment, but more drugs are now under clinical investigation, in line with new, recently discovered molecular and immunological pathways. This review describes potential new drugs for low and high-risk MDS. The increasing knowledge of immunological and signalling pathways in MDS will assist us in identifying targeted patient-oriented treatments. In the near future, initial molecular stratification will lead the way to a personalized approach and targeted therapy.

Estimates of Overall Survival in Patients With Cancer Receiving Different Treatment Regimens: Emulating Hypothetical Target Trials in the Surveillance, Epidemiology, and End Results (SEER)-Medicare Linked Database

IMPORTANCE

The Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database may provide insights into the comparative effectiveness of oncological treatments for elderly individuals who are underrepresented in clinical trials.

OBJECTIVE

To evaluate the suitability of SEER-Medicare data for assessing the effectiveness of adding a drug to an existing treatment regimen on the overall survival of elderly patients with cancer.

DESIGN, SETTING, AND PARTICIPANTS

This comparative effectiveness study analyzed SEER-Medicare data from 9549 individuals who received a new diagnosis of stage II colorectal cancer (2008-2012) and 940 patients who received a new diagnosis of advanced pancreatic adenocarcinoma (2007-2012), with follow-up to December 31, 2013 (SEER-Medicare data released in 2015). Two (hypothetical) target trials were designed and emulated based on 2 existing randomized clinical trials: (1) adjuvant fluorouracil after curative surgery for individuals with stage II colorectal cancer and (2) erlotinib added to gemcitabine for individuals with advanced pancreatic adenocarcinoma. Data were analyzed January 2018 to March 2019.

EXPOSURES

The following treatment strategies were compared: (1) fluorouracil initiation vs no initiation within 3 months of tumor resection and (2) erlotinib initiation vs no initiation within 12 weeks of gemcitabine initiation.

MAIN OUTCOMES AND MEASURES

All-cause mortality within 60 months of baseline for the fluorouracil trial and within 72 weeks for the erlotinib trial.

RESULTS

Compared with 3293 individuals in the existing fluorouracil trial, 9549 eligible individuals included in the present analyses were more likely to have colon cancer (8565 [90%] vs 2291 [71%]) and were older (median [interquartile range], 79 [73-84] vs 63 [56-68] years). The 5-year risk difference for initiation vs noninitiation of fluorouracil after surgery was -3.8% (95% CI, -14.8% to 12.6%), and the mortality hazard ratio (HR) was 0.95 (95% CI, 0.85-1.04). Compared with 569 individuals in the existing erlotinib trial, 940 eligible patients included in the present analysis were older (median [range], 74 [66-93] vs 64 [36-92] years) and more likely to be male (547 [58%] vs 298 [52%]). The 1-year risk difference for initiation vs noninitiation of erlotinib was 4.7% (95% CI, -9.4% to 18.0%), and the corresponding mortality HR was 1.04 (95% CI, 0.86-1.42). In naive analyses, the mortality HR estimate was 1.14 (95% CI, 0.95-1.36) for the fluorouracil emulation and 0.68 (95% CI, 0.54-0.87) for the erlotinib emulation.

CONCLUSIONS AND RELEVANCE

The present estimates were similar to those from randomized clinical trials that studied adding the same cancer drugs to existing regimens. The published HR was 1.02 (95% CI, 0.70-1.48) in the fluorouracil trial for individuals aged 70 or older and 0.96 (95% CI, 0.74-1.24) in the erlotinib trial for individuals aged 65 years or older. The SEER-Medicare database may be adequate for studying the real-world effectiveness of adding a drug to treatment regimens used for elderly individuals with cancer.

Comparison between 5-day decitabine and 7-day azacitidine for lower-risk myelodysplastic syndromes with poor prognostic features: a retrospective multicentre cohort study

Numerous studies have analysed the clinical efficacies of hypomethylating agents (HMAs) in patients with myelodysplastic syndromes (MDS). However, reports that compare the two HMAs, decitabine and azacitidine, in patients with lower-risk (low and intermediate-1) MDS are limited. We compared 5-day decitabine and 7-day azacitidine regimens in terms of treatment responses, survival outcomes, and adverse events in patients with lower-risk MDS with poor prognostic features. The overall response rates (ORRs) were 67.2% and 44.0% in the patients treated with decitabine and azacitidine, respectively (P = 0.014). While the median progression-free survival (PFS) was significantly better in the patients treated with decitabine than in those treated with azacitidine (P = 0.019), no significant differences in event-free and overall survival rates were observed between the two groups. Multivariate analysis revealed that compared with azacitidine treatment, decitabine treatment is significantly associated with a higher ORR (P = 0.026) and longer PFS (P = 0.037). No significant differences were observed in the incidence of grade 3 or higher haematologic adverse events in response to the two HMAs. In conclusion, in lower-risk MDS, especially with poor prognostic features, ORR and PFS were significantly better with 5-day decitabine treatment than with 7-day azacitidine treatment, with comparable safety.

Hypomethylating agents in the treatment of acute myeloid leukemia: A guide to optimal use

The hypomethylating agents (HMAs), decitabine and azacitidine, are valuable treatment options in acute myeloid leukemia patients who are not eligible for intensive chemotherapy. Both agents are generally well tolerated, and complications most commonly relate to myelosuppression. Antibiotic / antifungal use, regular monitoring, and proactive patient education are important to minimize these events, and reduce the need for dose delay. Responses to HMAs are often not evident for up to 6 cycles, and there is currently no validated clinical marker for predicting response. Hence, treatment should be continued for at least 4-6 cycles to ensure that patients have sufficient opportunity to respond. Delivery of insufficient numbers of cycles is a key reason for HMA failure, and premature discontinuation must be avoided. Genetic factors offer potential for better predicting responders to HMAs in future, but require further study.

What are the most promising new agents in myelodysplastic syndromes?

PURPOSE OF REVIEW

Myelodysplastic syndromes (MDS) are a diverse group of clonal disorders of hematopoietic stem or progenitor cells that represent the most common class of acquired bone marrow failure syndromes in adults. Despite significant improvement in the pathologic insight into this group of disorders, therapeutic options remain limited and allogeneic hematopoietic stem-cell transplantation is the only treatment that can induce long-term remission in patients with MDS. The goals of therapy for MDS are based on disease prognostication, with a focus of minimizing transfusion dependence and preserving quality of life in low-risk groups and preventing progression of disease to acute myeloid leukemia in high-risk groups. Given the dearth of approved treatment options, there is a marked need for novel therapies across the board, and there are several novel agents currently in the pipeline.

RECENT FINDINGS

Among the promising agents with preclinical and early phase efficacy in higher risk MDS, apoptosis targeting with BCL-2 inhibitors have been a standout. There is also a keen interest in immunotherapy, and targeted agents (genetic, signaling pathways, bispecific antibodies, antibody-drug conjugates, and others described in this review).

SUMMARY

In this review, we will highlight some of the promising new agents currently under investigation for the management of MDS.

Systematic review and meta-analysis of the effect of iron chelation therapy on overall survival and disease progression in patients with lower-risk myelodysplastic syndromes

The impact of iron chelation therapy (ICT) on overall survival (OS) and progression to acute myeloid leukemia (AML) in patients with iron overload and International Prognostic Scoring System low- or intermediate-risk myelodysplastic syndromes (MDS) is not well understood. We conducted a systematic review and meta-analysis of published studies of ICT in patients with MDS to better elucidate these relationships. We searched PubMed, EMBASE, Cochrane databases, and the World Health Organization Clinical Trial Registry for studies reporting the impact of ICT on OS in patients with low- or intermediate-risk MDS. Studies were examined for demographics, effect measures, and potential bias risk. Fixed and random-effects models were used to calculate adjusted OS and adjusted hazards ratio (aHR) estimates, respectively, among the different studies. Nine observational studies (four prospective and five retrospective) were identified. For patients with MDS, ICT was associated with an overall lower risk of mortality compared with no ICT (aHR 0.42; 95% confidence interval (CI) 0.28-0.62; P < 0.01); however, there was significant heterogeneity across the studies. In studies reporting progression to AML, ICT was not associated with decreased risk of progression (odds ratio 0.68; 95% CI 0.31-1.43; P < 0.030). This systematic review and meta-analysis of nine nonrandomized trials demonstrated significant reduction in risk of mortality in patients with iron overload and low- or intermediate-risk MDS treated with ICT; however, a causal relationship cannot be established. Randomized, controlled trials are needed to more definitively evaluate the relationship between ICT and survival in patients with iron overload and low- or intermediate-risk MDS.

Immunosuppressive therapy in myelodysplastic syndromes: a borrowed therapy in search of the right place

INTRODUCTION

Myelodysplastic syndromes (MDS) encompass a heterogenous collection of clonal hematopoietic stem cell disorders defined by dysregulated hematopoiesis, peripheral cytopenias, and a risk of leukemic progression. Increasing data support the role of innate and adaptive immune pathways in the pathogenesis and disease course of MDS. The role of immunosuppressive therapy has an established role in the treatment of other hematologic diseases, such as aplastic anemia whose pathogenesis is postulated to reflect that of MDS with regards to many aspects of immune activation. Areas covered: This paper discusses the current understanding of immune dysregulation as it pertains to MDS, the clinical experience with immunosuppressive therapy in the management of MDS, as well as future prospects which will likely improve therapeutic options and outcomes for patients with MDS. Expert commentary: Though limited by paucity of high quality data, immunomodulatory and immunosuppressive therapies for the treatment of MDS have shown meaningful clinical activity in selected patients. Continued clarification of the immune pathways that are dysregulated in MDS and establishing predictors for clinical benefit of immunosuppressive therapy are vital to improve the use and outcomes with these therapies.

Beyond the Edge of Hypomethylating Agents: Novel Combination Strategies for Older Adults with Advanced MDS and AML

Higher-risk myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) of the elderly exhibit several commonalities, including first line treatment with hypomethylating agents (HMA) like azacitidine (AZA) or decitabine (DAC). Until today, response to treatment occurs in less than 50 percent of patients, and is often short-lived. Moreover, patients failing HMA have a dismal prognosis. Current developments include combinations of HMA with novel drugs targeting epigenetic or immunomodulatory pathways. Other efforts focus on the prevention of resistance to HMA using checkpoint inhibitors to enhance immune attack. This review focuses on recent advances in the field of HMA-based front-line therapies in elderly patients with myeloid diseases.

DNA Methyltransferase Inhibitors in Myeloid Cancer: Clonal Eradication or Clonal Differentiation?

DNA methyltransferase inhibitors, so-called hypomethylating agents (HMAs), are the only drugs approved for the treatment of higher-risk myelodysplastic syndromes and are widely used in this context. However, it is still unclear why some patients respond to HMAs, whereas others do not. Recent sequencing efforts have identified molecular disease entities that may be specifically sensitive to these drugs, and many attempts are being made to clarify how HMAs affect the malignant clone during treatment. Here, we review the most recent data on the clinical effects of HMAs in myeloid malignancies.

More is less, less is more, or does it really matter? The curious case of impact of azacitidine administration schedules on outcomes in patients with myelodysplastic syndromes

Myelodysplastic syndromes (MDS) encompass a diverse group of hematologic disorders characterized by ineffective and malignant hematopoiesis, peripheral cytopenias and significantly increased risk of progression to acute myeloid leukemia (AML). The hypomethylating agents (HMA) azacitidine and decitabine induce meaningful clinical responses in a significant subset of patients with MDS. Though never compared directly with decitabine, only azacitidine has improved overall survival (OS) compared to conventional care in a randomized trial in patients with higher-risk MDS. The azacitidine regimen used in this pivotal trial AZA-001 included administration at 75 mg/m2/day for 7 consecutive days in 28-day cycles (7-0 regimen). Given the logistical difficulties of weekend administration in the 7-0 regimen, as well as in efforts to improve response rates, alternative dosing schedules have been used. In a typical 28-day cycle, administration schedules of 3, 5, 10, and (with the oral version of azacitidine) 14 and 21 days have been used in clinical trials. Most trials that evaluated alternative administration schedules of azacitidine did so in lower-risk MDS and did not directly compare to the 7-0 schedule. Given the lack of randomized prospective studies comparing the 7-0 schedule to the other regimens of azacitidine in MDS, Shapiro et al. conducted a systematic review in an attempt to answer this question. Here we place the findings of this important work in clinical context and review the current knowledge and unresolved issues regarding the impact of administration schedules of azacitidine on outcomes of patients with both lower-risk and higher-risk MDS.

NY-ESO-1 Vaccination in Combination with Decitabine Induces Antigen-Specific T-lymphocyte Responses in Patients with Myelodysplastic Syndrome

Purpose: Treatment options are limited for patients with high-risk myelodysplastic syndrome (MDS). The azanucleosides, azacitidine and decitabine, are first-line therapy for MDS that induce promoter demethylation and gene expression of the highly immunogenic tumor antigen NY-ESO-1. We demonstrated that patients with acute myeloid leukemia (AML) receiving decitabine exhibit induction of NY-ESO-1 expression in circulating blasts. We hypothesized that vaccinating against NY-ESO-1 in patients with MDS receiving decitabine would capitalize upon induced NY-ESO-1 expression in malignant myeloid cells to provoke an NY-ESO-1-specific MDS-directed cytotoxic T-cell immune response.Experimental Design: In a phase I study, 9 patients with MDS received an HLA-unrestricted NY-ESO-1 vaccine (CDX-1401 + poly-ICLC) in a nonoverlapping schedule every four weeks with standard-dose decitabine.Results: Analysis of samples serially obtained from the 7 patients who reached the end of the study demonstrated induction of NY-ESO-1 expression in 7 of 7 patients and NY-ESO-1-specific CD4⁺ and CD8⁺ T-lymphocyte responses in 6 of 7 and 4 of 7 of the vaccinated patients, respectively. Myeloid cells expressing NY-ESO-1, isolated from a patient at different time points during decitabine therapy, were capable of activating a cytotoxic response from autologous NY-ESO-1-specific T lymphocytes. Vaccine responses were associated with a detectable population of CD141^Hi conventional dendritic cells, which are critical for the uptake of NY-ESO-1 vaccine and have a recognized role in antitumor immune responses.Conclusions: These data indicate that vaccination against induced NY-ESO-1 expression can produce an antigen-specific immune response in a relatively nonimmunogenic myeloid cancer and highlight the potential for induced antigen-directed immunotherapy in a group of patients with limited options. Clin Cancer Res; 24(5); 1019-29. ©2017 AACRSee related commentary by Fuchs, p. 991.