Azacitidine in 302 patients with WHO-defined acute myeloid leukemia: results from the Austrian Azacitidine Registry of the AGMT-Study Group

Real-World Outcome and Prognostic Factors in MDS Patients Treated with Azacitidine-A Retrospective Analysis

Azacitidine (AZA) is recognized as a vital drug used in the therapy of myelodysplastic syndromes (MDS) due to its beneficial effect on survival and quality of life. Nevertheless, many patients fail to respond to AZA treatment, as prognostic factors still are not identified. The present retrospective analysis included 79 patients with MDS treated with AZA as first-line therapy in a real-life setting. The percentage of patients with good, intermediate, and poor cytogenetics was 46.8%, 11.4%, and 34.2%, respectively. The overall response rate (complete remission [CR], partial remission [PR], and hematological improvement [HI]) was 24%. The CR, PR, and HI rates were 13.9%, 2.5%, and 7.6%, respectively. Stable disease (SD) was documented in 40.5% of patients. The median overall survival (OS) and progression-free survival (PFS) were 17.6 and 14.96 months, respectively. Patients with ORR and SD had a significantly longer median OS (23.8 vs. 5.7 months, p = 0.0005) and PFS (19.8 vs. 3.5 months, p < 0.001) compared to patients who did not respond to AZA. In univariate analysis, only an unfavorable cytogenetic group was a prognostic factor of a lower response rate (p = 0.03). In a multivariate model, older age (p = 0.047), higher IPSS (International Prognostic Scoring System) risk (p = 0.014), and higher IPSS-R cytogenetic risk (p = 0.004) were independent factors of shorter OS. Independent prognostic factors for shorter PFS were age (p = 0.001), IPSS risk (p = 0.02), IPSS cytogenetic risk (p = 0.002), and serum ferritin level (p = 0.008). The safety profile of AZA was predictable and consistent with previous studies. In conclusion, our study confirms the efficacy and safety of AZA in a real-world population and identifies potential biomarkers for response and survival.

Spectrum of infections in different regimens of post-induction chemotherapy in acute myeloid leukemia (de-novo): A comparative retrospective study

Background

Patients diagnosed with acute myeloid leukemia (AML) face a heightened susceptibility to infections, which significantly elevates their risk of mortality and disability. The intensity of the chemotherapy treatment and its specific focus on inhibiting myeloid cell divisions render patients especially vulnerable, particularly during the early stages of chemotherapy. This vulnerability is compounded by the occurrence of repeated episodes of prolonged neutropenia, leaving patients highly susceptible to infections. The compromised immune systems of these individuals make them more susceptible to infections, which adversely affect their physical health and overall well-being. Consequently, our study aimed to investigate the range of infections experienced by patients with newly diagnosed AML undergoing different induction chemotherapy.

Methods

This was a comparative retrospective study, conducted at a tertiary hospital providing comprehensive cancer care in North India. All newly diagnosed patients with AML, who received induction chemotherapy from January 1, 2012 to November 1, 2022, were identified from the hospital database and included in this study.

Results

Four hundred and twenty AML patients treated with either high-intensity or low-intensity induction chemotherapy was observed in this study. It was found that patients who received high-intensity treatment had a higher rate of clinically and microbiologically documented infections, fever without a known cause, and more cases of febrile neutropenia than those who got low-intensity treatment. These differences between the two groups were particularly evident on day 14 (p = 0.0002) and persisted through day 28 (p = 0.005).

Conclusions

These findings underscore the effectiveness and downside of high-intensity induction chemotherapy regimens, as evidenced by the higher incidence of infections observed. Further investigation through prospective clinical studies is warranted to better evaluate and validate the efficacy of this approach.

Cox proportional hazards deep neural network identifies peripheral blood complete remission to be at least equivalent to morphologic complete remission in predicting outcomes of patients treated with azacitidine-A prospective cohort study by the AGMT

The current gold standard of response assessment in patients with myelodysplastic syndromes (MDS), chronic myelomonocytic leukemia (CMML), and acute myeloid leukemia (AML) is morphologic complete remission (CR) and CR with incomplete count recovery (CRi), both of which require an invasive BM evaluation. Outside of clinical trials, BM evaluations are only performed in ~50% of patients during follow-up, pinpointing a clinical need for response endpoints that do not necessitate BM assessments. We define and validate a new response type termed "peripheral blood complete remission" (PB-CR) that can be determined from the differential blood count and clinical parameters without necessitating a BM assessment. We compared the predictive value of PB-CR with morphologic CR/CRi in 1441 non-selected, consecutive patients diagnosed with MDS (n = 522; 36.2%), CMML (n = 132; 9.2%), or AML (n = 787; 54.6%), included within the Austrian Myeloid Registry (aMYELOIDr; NCT04438889). Time-to-event analyses were adjusted for 17 covariates remaining in the final Cox proportional hazards (CPH) model. DeepSurv, a CPH neural network model, and permutation-based feature importance were used to validate results. 1441 patients were included. Adjusted median overall survival for patients achieving PB-CR was 22.8 months (95%CI 18.9-26.2) versus 10.4 months (95%CI 9.7-11.2) for those who did not; HR = 0.366 (95%CI 0.303-0.441; p < .0001). Among patients achieving CR, those additionally achieving PB-CR had a median adjusted OS of 32.6 months (95%CI 26.2-49.2) versus 21.7 months (95%CI 16.9-27.7; HR = 0.400 [95%CI 0.190-0.844; p = .0161]) for those who did not. Our deep neural network analysis-based findings from a large, prospective cohort study indicate that BM evaluations solely for the purpose of identifying CR/CRi can be omitted.

Adverse Event Profile of Azacitidine: Analysis by Route of Administration Using Japanese Pharmacovigilance Database

INTRODUCTION

Azacitidine is a useful drug for myelodysplastic syndromes and acute myeloid leukemia. In clinical trials, hematologic toxicity and infection have been observed as adverse events (AEs) of this drug. However, information on the time to onset of high risk AEs and subsequent outcomes, as well as differences in the frequency of AEs due to the route of administration is lacking. In this study, we investigated azacitidine-induced AEs comprehensively using the Japanese Adverse Event Reporting Database (JADER) published by the Pharmaceuticals and Medical Devices Agency, with disproportionate analysis of AE incidence trends, time to onset, and subsequent outcomes. In addition, we analyzed the differences in AEs by route of administration and the number of days until the occurrence of AEs and generated hypotheses.

METHODS

The study used JADER data reported from April 2004 to June 2022. Risk estimation was conducted using reported odds ratio. A signal was detected when the lower limit of the 95% confidence interval of the calculated ROR was ≥1.

RESULTS

A total of 34 signals were detected as AEs due to azacitidine. Among them, 15 were hematologic toxicities and 10 were infections, which demonstrated a particularly high rate of death. Signals of AEs such as tumor lysis syndrome (TLS) and cardiac failure, which have been described in case reports, were also detected, and the rate of death after onset was high. In addition, more AEs generally occurred within the first month of treatment.

CONCLUSION

The results of this study suggest that more attention should be paid to cardiac failure, hematologic toxicity, infection, and TLS. Because many patients in clinical trials have discontinued treatment due to serious AEs before the therapeutic effect became apparent, appropriate supportive care, dose reduction, and drug withdrawal are important for the continuation of treatment.

Hypomethylating agent-based therapies in older adults with acute myeloid leukemia - A joint review by the Young International Society of Geriatric Oncology and European Society for Blood and Marrow Transplantation Trainee Committee

Acute myeloid leukemia (AML) is associated with poor outcomes in older adults. A major goal of treatment is to balance quality of life and functional independence with disease control. With the approval of new, more tolerable regimens, more older adults are able to receive AML-directed therapy. Among these options are hypomethylating agents (HMAs), specifically azacitidine and decitabine. HMAs have become an integral part of AML therapy over the last two decades. These agents are used either as monotherapy or nowadays more commonly in combination with other agents such as the Bcl-2 inhibitor venetoclax. Biological AML characteristics, such as molecular and cytogenetic risk factors, play crucial roles in guiding treatment decisions. In patients with high-risk AML, HMAs are increasingly used rather than intensive chemotherapy, although further trials based on a risk-adapted approach using patient- and disease-related factors are needed. Here, we review trials and evidence for the use of HMA monotherapy and combination therapy in the management of older adults with AML. Furthermore, we discuss the use of HMAs and HMA combination therapies in AML, mechanisms of action, their incorporation into hematopoietic stem cell transplantation strategies, and their use in patients with comorbidities and reduced organ function.

Clinical Utility of Azacitidine in the Management of Acute Myeloid Leukemia: Update on Patient Selection and Reported Outcomes

Acute myeloid leukemia (AML) is predominantly a disease of the elderly, and a significant proportion of these patients are not candidates for intensive, curative-intent therapies. Epigenetic dysregulation resulting in abnormal DNA hypermethylation is one of the hallmarks of AML pathogenesis. For the past two decades, hypomethylating agents including azacitidine (AZA) have been the mainstay of treatment for AML patients who are ineligible to receive intensive chemotherapies. As our understanding of AML disease biology has improved, several novel treatment combinations have been developed to improve the outcome of AML patients, with remarkable success. A considerable proportion of these novel combinations have utilized AZA as the backbone of their treatment scheme. In this review, we have highlighted the evolution of AML treatment, focusing on novel AZA-based treatment combinations and their clinical efficacy.

Adverse Events in 1406 Patients Receiving 13,780 Cycles of Azacitidine within the Austrian Registry of Hypomethylating Agents-A Prospective Cohort Study of the AGMT Study-Group

Simple Summary

Azacitidine is thus far the only drug shown to prolong overall survival and is, therefore, the recommended (backbone) treatment in patients diagnosed with myelodysplastic syndromes, chronic myelomonocytic leukemia and acute myeloid leukemia who are not eligible for intensive chemotherapy. Detailed reports on adverse events are often lacking. We performed a thorough analysis of the adverse events that occur during treatment with azacitidine in the largest cohort of patients treated with this drug published so far. We also compared the frequency of adverse events documented in our cohort to published data from randomized clinical trials with an azacitidine monotherapy arm. Adverse event documentation in the Austrian Registry was high. Hematologic adverse events occurred at a similar rate compared to published trials, whereas gastrointestinal toxicities were significantly less commonly reported. Our data complement results from clinical trials with real-world evidence and form a reference for future combination strategies with azacitidine.

Abstract

Background: Azacitidine is the treatment backbone for patients with acute myeloid leukemia, myelodysplastic syndromes and chronic myelomonocytic leukemia who are considered unfit for intensive chemotherapy. Detailed reports on adverse events in a real-world setting are lacking. Aims: To analyze the frequency of adverse events in the Austrian Registry of Hypomethylating agents. To compare real-world data with that of published randomized clinical trials. Results: A total of 1406 patients uniformly treated with a total of 13,780 cycles of azacitidine were analyzed. Hematologic adverse events were the most common adverse events (grade 3–4 anemia 43.4%, grade 3–4 thrombopenia 36.8%, grade 3–4 neutropenia 36.1%). Grade 3–4 anemia was significantly more common in the Registry compared to published trials. Febrile neutropenia occurred in 33.4% of patients and was also more common in the Registry than in published reports. Other commonly reported adverse events included fatigue (33.4%), pain (29.2%), pyrexia (23.5%), and injection site reactions (23.2%). Treatment termination due to an adverse event was rare (5.1%). Conclusion: The safety profile of azacitidine in clinical trials is reproducible in a real-world setting. With the use of prophylactic and concomitant medications, adverse events can be mitigated and azacitidine can be safely administered to almost all patients with few treatment discontinuations.

Low serum albumin level deteriorates prognosis in azacitidine-treated myelodysplastic syndromes patients - results of the PALG study 'PolAZA'

BACKGROUND

Azacitidine (AZA) is the standard of care for higher-risk myelodysplastic syndrome (HR-MDS) patients ineligible for intensive therapy. Clinical outcome discrepancies reported in clinical trials and real-life settings stimulate the search for new prognostic factors.

METHODS

We retrospectively evaluated 315 MDS, 20-30% blast acute myeloid leukemia (AML) and chronic myelomonocytic leukemia (CMML) patients treated with azacitidine in 12 centers cooperating within the Polish Adult Leukemia Group (PALG).

RESULTS

The median number of AZA cycles was 7 (1-69) and 24% patients received fewer than 4 cycles (early failure, EF). Serum albumin level was an independent predictor of EF occurrence. Complete remission (CR) was obtained in 20% and partial remission (PR) in 12% of patients. Hematologic improvement - erythroid (HI-E), neutrophil (HI-N), or platelet (HI-P) was achieved in 51%, 36%, and 48% of patients, respectively. No factors significantly predicted CR or PR in the multivariate analysis. For HI-E and HI-P, lower LDH level predicted response. Median survival was 15 (13-19) months. Lower serum albumin level, serious infection and receiving <4 AZA cycles independently predicted a worse overall survival (OS) (p < 0.05).

CONCLUSION

Serum albumin assessment before azacitidine treatment can help to identify patients with higher risk of early failure and worse clinical outcome.

Resistance to venetoclax and hypomethylating agents in acute myeloid leukemia

Despite the success of the combination of venetoclax with the hypomethylating agents (HMA) decitabine or azacitidine in inducing remission in older, previously untreated patients with acute myeloid leukemia (AML), resistance - primary or secondary - still constitutes a significant roadblock in the quest to prolong the duration of response. Here we review the proposed and proven mechanisms of resistance to venetoclax monotherapy, HMA monotherapy, and the doublet of venetoclax and HMA for the treatment of AML. We approach the mechanisms of resistance to HMAs and venetoclax in the light of the agents' mechanisms of action. We briefly describe potential therapeutic strategies to circumvent resistance to this promising combination, including alternative scheduling or the addition of other agents to the HMA and venetoclax backbone. Understanding the mechanisms of action and evolving resistance in AML remains a priority in order to maximize the benefit from novel drugs and combinations, identify new therapeutic targets, define potential prognostic markers, and avoid treatment failure.

Predictive factors for response and survival in elderly acute myeloid leukemia patients treated with hypomethylating agents: a real-life experience

Predictive factors of response to hypomethylating agents (HMA) in elderly acute myeloid leukemia (AML) patients remain unclear in the real-life setting and no direct comparison between azacitidine (AZA) and decitabine (DEC) has been carried out. We retrospectively evaluated 110 AML patients treated with HMA (78 AZA, 32 DEC) as first-line therapy outside of clinical trials. Median age was 75 years (range 58-87). The median overall survival (OS) of the entire cohort was 8.0 months (95% CI 6.1-10), without significant differences among the subgroups: AZA 8.8 months vs DEC 6.3 months (p = 0.291). HMA treatment yielded an overall response rate (ORR) of 40% (AZA 37% vs DEC 47%, p = 0.237). A stable disease (SD) after 4 HMA cycles was not associated with a worse survival outcome compared with an early optimal response. Factors independently associated with a better OS were transfusion independence during treatment (p = 0.049), achievement of an optimal response to treatment (p < 0.001), and a baseline hemoglobin level ≥ 9.25 (p = 0.018). A bone marrow (BM) blast count ≥ 30% (p < 0.001) and a therapy-related AML (p = 0.008) remain poor survival predictors. Of the available biologic features, an adverse risk category according to the ELN classification was significantly associated with a shorter survival over the intermediate risk category (p = 0.034). Disease progression remains the primary cause of death. Infectious complications were more severe (p = 0.036) and occurred earlier (p = 0.006) in the DEC group compared with that of the AZA group. In conclusion, clinical prognostic factors associated to response and survival have been identified without significant associations concerning overall outcomes between the two HMAs.

Estimated glomerular filtration rate independently predicts outcome of azacitidine therapy in higher-risk Myelodysplastic syndromes. Results from 536 patients of the Hellenic National Registry of Myelodysplastic and Hypoplastic syndromes

Higher-risk Myelodysplastic syndromes (MDS) patients undergoing treatment with 5-azacytidine (AZA) are typically elderly with several comorbidities. However, the effect of comorbidities on the effectiveness and safety of AZA in real-world settings remains unclear. We analyzed data from 536 AZA-treated patients with higher-risk MDS, Myelodysplastic/Myeloproliferative neoplasms and low blast count Acute Myeloid Leukemia enrolled to the Hellenic National Registry of Myelodysplastic and Hypoplastic Syndromes. Multivariate analysis adjusted also for the International Prognostic Scoring System (IPSS), its revised version (IPSS-R) and the French Prognostic Scoring System (FPSS), demonstrated independent associations of overall and leukemia-free survival with estimated glomerular filtration rate (eGFR) <45 mL min^-1 /1.73 m² (P = .039, P = .023, respectively), ECOG performance status <2 (P = .015, P = .006), and presence of peripheral blood blasts (P = .008, P = .034), while secondary MDS also correlated with significantly shorter leukemia-free survival (P = .039). Addition of eGFR <45 mL min^-1 /1.73 m² , in IPSS-R and FPSS increased the predictive power of both models. Only FPSS ≤2 and eGFR <45 mL min^-1 /1.73 m² predicted worse response to AZA in multivariate analysis, whereas eGFR <45 mL min^-1 /1.73 m² correlated significantly with death from hemorrhage (P = .003) and cardiovascular complications (P = .006). In conclusion, in the second largest real-world series of AZA-treated MDS patients, we show that an eGFR <45 mL min^-1 /1.73 m² is an independent predictor of worse response and survival. This higher cut-off, instead of the commonly used serum creatinine >2 mg/dL, can be utilized as a more precise indicator of renal comorbidity during AZA therapy. Incorporation of eGFR in the prognostic assessment of AZA-treated MDS patients may prove useful not only in routine practice, but also for the appropriate patient stratification in clinical trials with AZA combinations.

Low-intensity regimens versus standard-intensity induction strategies in acute myeloid leukemia

Treatment options for elderly patients with acute myeloid leukemia (AML) remain limited. In this age group, AML is frequently associated with poor-risk features, while patients’ present comorbidities and reduced functional reserves. As such, intensive chemotherapy (ICT) is frequently too toxic or ineffective in elderly patients and is restricted to a select minority, though it is standard therapy for the youngest and fittest patients or for those belonging to either the favorable or intermediate-risk groups. The use of hypomethylating agents represent an effective alternative for patients who are unfit for ICT, yet the results remain unsatisfactory. In recent years, prognostic scores were developed that include geriatric assessment tools and improved risk-stratification. In addition, several effective new drugs have emerged. The combination of these drugs with hypomethylating agents or low-dose cytarabine has produced encouraging preliminary results that may change standard practices and offer an alternative to the dilemma of ICT versus low-intensity therapies.

Pracinostat plus azacitidine in older patients with newly diagnosed acute myeloid leukemia: results of a phase 2 study

Pracinostat, a potent oral pan-histone deacetylase inhibitor with modest single-agent activity in acute myeloid leukemia (AML), has shown synergistic antitumor activity when combined with azacitidine. This single-group, multicenter phase 2 study assessed the safety and efficacy of pracinostat combined with azacitidine in patients who were at least 65 years old with newly diagnosed AML and who were ineligible for standard induction chemotherapy. Patients received pracinostat 60 mg/d, 3 d/wk, for 3 consecutive weeks, plus azacitidine 75 mg/m² daily for 7 days in a 28-day cycle. Primary endpoints were complete remission (CR), CR with incomplete count recovery (CRi), and morphologic leukemia-free state (MLFS) rates of the combination. Secondary endpoints included safety, progression-free survival (PFS), and overall survival (OS) of the regimen. Fifty patients (33 de novo, 12 secondary, and 5 therapy-related AML) were enrolled. Twenty-six patients (52%) achieved the primary endpoint of CR (42%), CRi (4%), and MLFS (6%). Median OS and PFS were 19.1 months (95% confidence interval [CI], 10-26.5 months) and 12.6 months (95% CI, 10-17.7 months), respectively, with a 1-year OS rate of 62%. Forty-three patients (86%) experienced at least 1 grade 3 or worse treatment-emergent adverse event with the combination, with infections (52%), thrombocytopenia (46%), and febrile neutropenia (44%) reported as the most common toxicities. The 30- and 60-day all-cause mortality rates were 2% and 10%, respectively. DNA sequencing revealed somatic mutations at baseline, and clearance rates correlated with response to treatment. Pracinostat plus azacitidine is a well-tolerated and active regimen in the frontline treatment of older patients with AML unfit for intensive therapy. A larger controlled trial is ongoing. This trial was registered at www.clinicaltrials.gov as #NCT01912274.

Hypomethylating Agents Use in Acute Myeloid Leukemia: A Single-Center Experience

Context: Acute myeloid leukemia (AML) is a heterogeneous disease. Approximately 80% of older AML patients will die of their disease or its treatment with currently available antileukemic therapy because of the adverse prognostic risk factors. In elderly patients who are not candidates for induction chemotherapy (IC) or who declines IC, the preferred induction regimen is with hypomethylating agents (HMAs). In India, data regarding therapy with HMA, response to therapy and overall survival (OS) is seldom reported. Aims: This study aims to study the response rate and survival of patients treated with HMAs in whom IC was not feasible. Settings and Design: This is retrospective and descriptive single-center study. Subjects and Methods: Data of newly diagnosed AML patients who were unfit for IC and treated with HMA in our institution was collected retrospectively and analyzed. Results: Twenty-three patients received HMAs as a treatment for AML. Eight (34.7%) of 23 patients had initial response to therapy (two [25%] had complete remission [CR], four [50%] had CR with incomplete hematologic recovery, one [12.5%] had partial remission) and one (12.5%) had stable disease. The median progression-free survival and OS observed are 6.06 ± 0.65 months and 7 ± 1.32 months, respectively. Conclusions: HMAs provide an important additional treatment option in newly diagnosed AML patients who are older, with poor performance status, higher comorbidity indices, and who refuse IC.

Advances in non-intensive chemotherapy treatment options for adults diagnosed with acute myeloid leukemia

Acute myeloid leukemia (AML) is primarily a disease of older adults. Many older patients with AML are not candidates for intensive chemotherapy regimens aimed at inducing remission before transplantation. The prognosis for this patient population remains poor, with 5-year overall survival (OS) rates of less than 10 %. At present, there is no standard of care, and clinical trials should be considered. Hypomethylating agents often are the mainstay of treatment in this setting; however, improved genetic profiling and risk stratification based on molecular, biological, and clinical characteristics of AML enhance the ability to identify an individual patient's risk and can refine therapeutic options. Over the past 2 years, several novel agents have been approved for AML patients in either the frontline or relapsed settings. Additional agents have also shown promising activity. It is becoming a challenge for physicians to navigate these different options and select the optimal therapy or combination of therapies. The aim of this review is to summarize the available information to assist with treatment decisions for leukemia patients who are not suitable for intensive chemotherapy.

Randomized phase-II trial evaluating induction therapy with idarubicin and etoposide plus sequential or concurrent azacitidine and maintenance therapy with azacitidine

The aim of this randomized phase-II study was to evaluate the effect of substituting cytarabine by azacitidine in intensive induction therapy of patients with acute myeloid leukemia (AML). Patients were randomized to four induction schedules for two cycles: STANDARD (idarubicin, cytarabine, etoposide); and azacitidine given prior (PRIOR), concurrently (CONCURRENT), or after (AFTER) therapy with idarubicin and etoposide. Consolidation therapy consisted of allogeneic hematopoietic-cell transplantation or three courses of high-dose cytarabine followed by 2-year maintenance therapy with azacitidine in the azacitidine-arms. AML with CBFB-MYH11, RUNX1-RUNX1T1, mutated NPM1, and FLT3-ITD were excluded and accrued to genotype-specific trials. The primary end point was response to induction therapy. The statistical design was based on an optimal two-stage design applied for each arm separately. During the first stage, 104 patients (median age 62.6, range 18-82 years) were randomized; the study arms PRIOR and CONCURRENT were terminated early due to inefficacy. After randomization of 268 patients, all azacitidine-containing arms showed inferior response rates compared to STANDARD. Event-free and overall survival were significantly inferior in the azacitidine-containing arms compared to the standard arm (p < 0.001 and p = 0.03, respectively). The data from this trial do not support the substitution of cytarabine by azacitidine in intensive induction therapy.

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.

[Diagnosis and treatment of acute myeloid leukemia : The updated 2018 Onkopedia Guideline]

In April 2018, an updated version of the previously published guidelines on acute myeloid leukemia (AML) from 2010 and 2017 was released. A revision was necessary because of two positive aspects: First, new data and insights on risk stratification and monitoring, and second, the clinical development and approval of new agents. The modified genetic risk classification allows a more precise distinction of different diagnostic groups and consequently a better matched post-remission treatment. The availability of new targeted drugs such as inhibitors turns genetic analyses from a mere prognostic tool into an instrument for treatment decisions. Several recently approved agents expand the treatment options for AML and raise hope for an improved prognosis and cure in the future.

Next Generation Sequencing in AML-On the Way to Becoming a New Standard for Treatment Initiation and/or Modulation?

Acute myeloid leukemia (AML) is a clonal disease caused by genetic abberations occurring predominantly in the elderly. Next generation sequencing (NGS) analysis has led to a deeper genetic understanding of the pathogenesis and the role of recently discovered genetic precursor lesions (clonal hematopoiesis of indeterminate/oncogenic potential (CHIP/CHOP)) in the evolution of AML. These advances are reflected by the inclusion of certain mutations in the updated World Health Organization (WHO) 2016 classification and current treatment guidelines by the European Leukemia Net (ELN) and National Comprehensive Cancer Network (NCCN) and results of mutational testing are already influencing the choice and timing of (targeted) treatment. Genetic profiling and stratification of patients into molecularly defined subgroups are expected to gain ever more weight in daily clinical practice. Our aim is to provide a concise summary of current evidence regarding the relevance of NGS for the diagnosis, risk stratification, treatment planning and response assessment in AML, including minimal residual disease (MRD) guided approaches. We also summarize recently approved drugs targeting genetically defined patient populations with risk adapted- and individualized treatment strategies.

Predictive Model for Infection Risk in Myelodysplastic Syndromes, Acute Myeloid Leukemia, and Chronic Myelomonocytic Leukemia Patients Treated With Azacitidine; Azacitidine Infection Risk Model: The Polish Adult Leukemia Group Study

BACKGROUND

Myelodysplastic syndromes (MDS), chronic myelomonocytic leukemia (CMML), and acute myeloid leukemia (AML) patients, including those treated with azacitidine, are at increased risk for serious infections. The aim of our study was to identify patients with higher infectious risk at the beginning of azacitidine treatment.

PATIENTS AND METHODS

We performed a retrospective evaluation of 298 MDS/CMML/AML patients and included in the analysis 232 patients who completed the first 3 cycles of azacitidine therapy or developed Grade III/IV infection before completing the third cycle.

RESULTS

Overall, 143 patients (62%) experienced serious infection, and in 94 patients (41%) infection occurred within the first 3 cycles. The following variables were found to have the most significant effect on the infectious risk in multivariate analysis: red blood cell transfusion dependency (odds ratio [OR], 2.38; 97.5% confidence interval [CI], 1.21-4.79), neutropenia <0.8 × 10⁹/L (OR, 3.03; 97.5% CI, 1.66-5.55), platelet count <50 × 10⁹/L (OR, 2.63; 97.5% CI, 1.42-4.76), albumin level <35 g/dL (OR, 2.04; 97.5% CI, 1.01-4.16), and Eastern Cooperative Oncology Group performance status ≥2 (OR, 2.19; 97.5% CI, 1.40-3.54). Each of these variables is assigned 1 point, and the combined score represents the proposed Azacitidine Infection Risk Model. The infection rate in the first 3 cycles of therapy in lower-risk (0-2 score) and higher-risk (3-5 score) patients was 25% and 73%, respectively. The overall survival was significantly reduced in higher-risk patients compared with the lower-risk cohort (8 vs. 29 months).

CONCLUSION

We selected a subset with high early risk for serious infection and worse clinical outcome among patients treated with azacitidine.

Extended dosing with CC-486 (oral azacitidine) in patients with myeloid malignancies

CC‐486 (oral azacitidine) is an epigenetic modifier in clinical development for treatment of hematological cancers. This study of extended CC‐486 dosing included patients with myelodysplastic syndromes (MDSs), chronic myelomonocytic leukemia (CMML), or acute myeloid leukemia (AML). After a pharmacokinetic assessment period, 31 patients (MDS n = 18, CMML n = 4, and AML n = 9) entered a clinical phase in which they received CC‐486 300 mg once‐daily for 21 days of repeated 28‐day cycles. Median age was 71 years (range: 53‐93); 42% of patients were aged ≥75 years. A total of 5 patients with AML (63%) had prior MDS. Median number of CC‐486 treatment cycles was 4 (range: 1‐32). The most common treatment‐emergent adverse events (TEAEs) were gastrointestinal (84% of patients) and hematologic (81%). Most common grade 3‐4 TEAEs were neutropenia (n = 13, 42%) and anemia (n = 9, 29%). Ten patients experienced grade 4 neutropenia. Infrequently, CC‐486 dose was interrupted or reduced due to gastrointestinal (n = 5, 16%) or hematologic (n = 6, 19%) TEAEs. Overall response rate (complete remission [CR], CR with incomplete hematological recovery [CRi], partial remission [PR], marrow CR) in the MDS/CMML subgroups was 32% and in the AML subgroup (CR/CRi/PR) was 22%. Red blood cell transfusion independence rates in the MDS/CMML and AML subgroups were 33% and 25%, respectively, and 2 MDS/CMML patients attained hematologic improvement as a best response on‐study. No baseline gene mutation was predictive of response/nonresponse. CC‐486 allows flexible dosing and schedules to improve tolerability or response. Neutropenia in early treatment cycles deserves scrutiny and may warrant initiation of prophylactic antibiotics.

KEY POINTS

The safety profile of oral CC‐486 was comparable to that of injectable azacitidine; most adverse events were hematological and gastrointestinal.

Extended (21‐day/cycle) CC‐486 dosing induced responses in patients with hematological malignancies, many of whom had prior DNMTi failure.

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.

Time to repeal and replace response criteria for acute myeloid leukemia?

The International Working Group (IWG) response criteria for acute myeloid leukemia, published in 2003, have remained the standard by which the efficacy of new drugs is measured in clinical trials. Over the last decade, concepts related to treatment response have been challenged by several factors; for example, the dissociation between early clinical response and survival outcome in older patients, the recognition that epigenetic and newer differentiating-agent therapies may produce delayed responses and also hematologic improvement/transfusion independence without a morphologic response, and evidence that remissions without minimal (or measurable) residual disease (MRD) may result in outcomes superior to those of morphologic remissions with persistent MRD. The evolving role of MRD status as a potential surrogate for predicting long-term survival has enhanced the clinical need to standardize and incorporate emerging technologies that enable deeper responses beyond those recognized by the IWG, and to pre-emptively identify patients at risk of early relapse. The potential for therapeutic interventions to erase MRD and alter the natural history represents an important and open research question. Reviewed here are some of the implications and challenges associated with establishing and incorporating new treatment response criteria, initially into clinical research, and eventually into real-world practice.

Azacitidine in Lower-Risk Myelodysplastic Syndromes: A Meta-Analysis of Data from Prospective Studies

BACKGROUND

After erythropoiesis-stimulating agent (ESA) failure, lenalidomide and hypomethylating agents are the only remaining treatment options for most patients with lower-risk myelodysplastic syndromes (LR-MDS). Optimal choice of these agents as front-line therapy in non-del(5q) LR-MDS is unclear. Because azacitidine clinical data mainly describe experience in higher-risk MDS, we performed a meta-analysis of patient-level data to evaluate azacitidine in patients with red blood cell (RBC) transfusion-dependent LR-MDS.

MATERIALS AND METHODS

We searched English-language articles for prospective phase II and III azacitidine clinical trials and patient registries published between 2000 and 2015, and Embase abstracts from 2015 conferences. Patient-level data from identified relevant studies were provided by investigators. Meta-analyses followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Efficacy endpoints were RBC transfusion independence (TI) and Clinical Benefit (RBC-TI, erythroid response, and complete or partial remission, per International Working Group 2006 criteria for MDS).

RESULTS

Data for 233 patients from 6 clinical studies and 1 registry study met criteria for inclusion in analyses. Overall, 90.3% of patients had non-del(5q) LR-MDS. Pooled estimates from random-effects models of RBC-TI and Clinical Benefit were 38.9% and 81.1%, respectively; for the ESA-refractory subgroup, they were 40.5% and 77.3%; and for patients with isolated anemia, they were 41.9% and 82.5%. In multivariate analyses, planned use of ≥6 azacitidine treatment cycles was significantly predictive of response.

CONCLUSION

Azacitidine effects in these patients, most with non-del(5q) LR-MDS, were promising and generally similar to those reported for lenalidomide in similar patients. The choice of initial therapy is important because most patients eventually stop responding to front-line therapy and alternatives are limited.

IMPLICATIONS FOR PRACTICE

Lower-risk myelodysplastic syndromes (LR-MDS) are primarily characterized by anemia. After erythropoiesis-stimulating agent (ESA) failure, lenalidomide and hypomethylating agents are the only remaining treatment options for most patients. This meta-analysis of 233 azacitidine-treated red blood cell (RBC) transfusion-dependent patients with LR-MDS (92.3% non-del[5q]) from 7 studies showed 38.9% became RBC transfusion-independent. There is no clear guidance regarding the optimal choice of lenalidomide or hypomethylating agents for patients with non-del(5q) LR-MDS following ESA failure. Clinical presentation (e.g., number of cytopenias) and potential outcomes after hypomethylating agent failure are factors to consider when making initial treatment decisions for LR-MDS patients.

Pevonedistat, a first-in-class NEDD8-activating enzyme inhibitor, combined with azacitidine in patients with AML

Pevonedistat (TAK-924/MLN4924) is a novel inhibitor of NEDD8-activating enzyme (NAE) with single-agent activity in relapsed/refractory acute myeloid leukemia (AML). We performed a phase 1b study of pevonedistat (PEV) with azacitidine (AZA) based on synergistic activity seen preclinically. Primary objectives included safety and tolerability, and secondary objectives included pharmacokinetics (PK) and disease response. Patients ≥60 years with treatment-naive AML (unfit for standard induction therapy) received PEV 20 or 30 mg/m² IV on days 1, 3, and 5 combined with fixed-dose AZA (75 mg/m² IV/subcutaneously) on days 1 to 5, 8, and 9, every 28 days. The most common treatment-emergent adverse events were constipation (48%), nausea (42%), fatigue (42%), and anemia (39%). In total, 11 deaths were observed and considered unrelated to study therapy by the investigators. Transient elevations in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were dose limiting. The recommended phase 2 dose (RP2D) of PEV in this combination is 20 mg/m² PEV PK was not altered by the addition of AZA. Overall response rate (ORR) based on an intent-to-treat analysis was 50% (20 complete remissions [CRs], 5 complete remission with incomplete peripheral count recovery, 7 partial remissions [PRs]), with an 8.3-month median duration of remission. In patients receiving ≥6 cycles of therapy (n = 23, 44%), ORR was 83%. In patients with TP53 mutations, the composite CR/PR rate was 80% (4/5). Two of these patients stayed on study for >10 cycles. Baseline bone marrow blast percentage or cytogenetic/molecular risk did not influence ORR. This study was registered at www.clinicaltrials.gov as #NCT01814826.

Risk of infection in elderly patients with AML and MDS treated with hypomethylating agents

The aim of this small volume is to raise awareness among Italian hematologists using hypomethylating drugs about risk - and even more important about “risk management” - and the treatment of the infectious events that may arise during therapy with these drugs. Since we wanted this review to be an extremely practical tool, we have included the most recent clinical case studies, the indications provided by the guidelines and expert opinions. Infectious complications are among the most common adverse events that can arise during treatment with hypomethylating drugs. For this reason, a large portion of the chapters of this small volume has been dedicated to a detailed description (on the basis of an attentive review of the literature) of what the hematologist can expect to encounter in terms of risk of infection, in patients treated with azacitidine or decitabine, and to the preventive investigations to carry out and the active prophylaxis measures recommended before commencing treatment with these drugs. What led us to write this book was the conviction that the critical sharing of the studies published in literature and of our personal experiences could contribute to prompting reflection on how we operate and that this, in turn, would lead to the best possible management of these treatments, both in patients with myelodysplasia and in patients with acute myeloid leukemia, preventing - and efficiently managing - infectious events - during therapy. We should not be misled by the fact that the treatments are prevalently administered on an outpatient basis; these patients due to their disease and, in particular, to their age, are extremely frail, and infectious and hemorrhagic complications are the main causes of their admissions to hospital. But expert knowledge and management of the risks of infection can guarantee better management of their needs on an outpatient basis, with undeniable advantages for the clinic but, first and foremost, for the patients. (www.actabiomedica.it)

How and when to decide between epigenetic therapy and chemotherapy in patients with AML

Remission induction with chemotherapy has long been the frontline treatment of acute myeloid leukemia (AML). However, intensive therapy is limited in frail patients by its associated toxicity and higher rates of failure or relapse in patients with chemoresistant disease, such as secondary AML or poor-risk cytogenetics. Frailty and chemoresistance are more frequent in older adults with AML. In recent years, epigenetic therapies with the hypomethylating agents decitabine and azacitidine have been thoroughly explored in AML. The results of two pivotal studies carried out with these agents in older adults with newly diagnosed AML have challenged the role of intensive chemotherapy as the frontline treatment option in this high-risk population. Here, we review the results of treatment with intensive chemotherapy and hypomethylating agents in older patients with AML; discuss the patient- and disease-specific criteria to integrate into treatment decision making; and also, highlight the methodological limitations of cross-study comparison in this population.

Outcome of Azacitidine Therapy in Acute Myeloid Leukemia Is not Improved by Concurrent Vorinostat Therapy but Is Predicted by a Diagnostic Molecular Signature

Purpose: Azacitidine (AZA) is a novel therapeutic option in older patients with acute myeloid leukemia (AML), but its rational utilization is compromised by the fact that neither the determinants of clinical response nor its mechanism of action are defined. Co-administration of histone deacetylase inhibitors, such as vorinostat (VOR), is reported to improve the clinical activity of AZA, but this has not been prospectively studied in patients with AML.Experimental Design: We compared outcomes in 259 adults with AML (n = 217) and MDS (n = 42) randomized to receive either AZA monotherapy (75 mg/m2 × 7 days every 28 days) or AZA combined with VOR 300 mg twice a day on days 3 to 9 orally. Next-generation sequencing was performed in 250 patients on 41 genes commonly mutated in AML. Serial immunophenotyping of progenitor cells was performed in 47 patients.Results: Co-administration of VOR did not increase the overall response rate (P = 0.84) or overall survival (OS; P = 0.32). Specifically, no benefit was identified in either de novo or relapsed AML. Mutations in the genes CDKN2A (P = 0.0001), IDH1 (P = 0.004), and TP53 (P = 0.003) were associated with reduced OS. Lymphoid multipotential progenitor populations were greatly expanded at diagnosis and although reduced in size in responding patients remained detectable throughout treatment.Conclusions: This study demonstrates no benefit of concurrent administration of VOR with AZA but identifies a mutational signature predictive of outcome after AZA-based therapy. The correlation between heterozygous loss of function CDKN2A mutations and decreased OS implicates induction of cell-cycle arrest as a mechanism by which AZA exerts its clinical activity. Clin Cancer Res; 23(21); 6430-40. ©2017 AACR.

Hypomethylating Agents as a Therapy for AML

Acute myeloid leukemia (AML) is predominantly a disease of older adults associated with poor long-term outcomes with available therapies. Used as single agents, hypomethylating agents (HMAs) induce only 15 to 25% complete remissions, but current data suggest that median OS observed after HMAs is comparable to that observed after more intensive therapies. Whether long-term cure may be obtained in some patients treated with HMAs is unknown. Combinations of HMAs to novel agents are now extensively investigated and attractive response rates have been reported when combining HMAs to different drug classes. The absence of reliable predictive biomarkers of efficacy of HMAs in AML and the uncertainties regarding their most relevant mechanisms of action hinder the rational design of the combinations to be tested in priority, usually in untreated older AML patients.

Molecular targeting in acute myeloid leukemia

Acute myeloid leukemia (AML) is a heterogenous disease associated with distinct genetic and molecular abnormalities. Somatic mutations result in dysregulation of intracellular signaling pathways, epigenetics, and apoptosis of the leukemia cells. Understanding the basis for the dysregulated processes provides the platform for the design of novel targeted therapy for AML patients. The effort to devise new targeted therapy has been helped by recent advances in methods for high-throughput genomic screening and the availability of computer-assisted techniques for the design of novel agents that are predicted to specifically inhibit the mutant molecules involved in these intracellular events. In this review, we will provide the scientific basis for targeting the dysregulated molecular mechanisms and discuss the agents currently being investigated, alone or in combination with chemotherapy, for treating patients with AML. Successes in molecular targeting will ultimately change the treatment paradigm for the disease.

Real life experience with frontline azacitidine in a large series of older adults with acute myeloid leukemia stratified by MRC/LRF score: results from the expanded international E-ALMA series (E-ALMA+)

Azacitidine (AZA) prolonged overall survival (OS) in the AZA-AML-001 trial. However, few subjects were randomized to AZA or intensive chemotherapy (IC). The Medical Research Council (MRC) and the Leukemia Research Foundation (LRF) developed a score for older AML patients receiving IC or non-intensive regimens, whereas the E-ALMA study validated a score for survival and response in elderly patients receiving AZA in daily practice. Both identified three groups with different risk estimates. This analysis evaluates the efficacy of frontline AZA in older AML patients (N = 710) unfit for IC from different national registries (E-ALMA + series) stratified by the MRC/LRF risk score. Median OS of patients categorized as good, standard and poor-risk groups by the MRC/LRF score was 13.4 (95% CI, 10.8-16), 12.4 (95% CI, 9.9-14.8), and 8.1 months (95% CI, 7-9.1), respectively (p = .0001). In conclusion, this is the largest retrospective cohort of older AML patients treated with AZA.

Treatment of Low-Blast Count AML using Hypomethylating Agents

In 2002, the WHO classification reduced the proportion of blasts in the bone marrow (BM) necessary for the diagnosis of acute myeloid leukemia (AML) from 30% to 20%, eliminating the RAEB-t subtype of myelodysplastic syndromes (MDS). However, this AML subtype, defined as low-blast count AML (LBC-AML, with 20-30% BM-blasts) is characterized by peculiar features, as increased frequency in elderly individuals and after cytotoxic treatment for a different primary disease (therapy-related), poor-risk cytogenetics, lower white blood cell counts, and less frequent mutations of NPM1 and FLT3 genes. The clinical course of this entity is often similar to MDS with 10-19% BM-blasts. The hypomethylating agents azacitidine and decitabine have been shown to induce responses and prolong survival both in MDS and LBC-AML. The role of these agents has also been demonstrated in AML with >30% BM-blasts, particularly in patients with poor-risk cytogenetics and in AML with myelodysplasia-related changes. Most recent studies are evaluating strategies to improve outcome, including combinations of hypomethylating agents with immune-response checkpoint inhibitors, which have a role in cancer immune surveillance. Efforts are also ongoing to identify mutations which may predict response and survival in these patients.

Azacitidine in adult patients with acute myeloid leukemia

Azacitidine is recommended front-line treatment for older patients with acute myeloid leukemia (AML) who are not candidates for intensive treatment regimens, and was recently granted approval in the European Union for treatment of adult AML. Reviewed here is azacitidine experience in AML, including: mechanistic and pharmacokinetic data; safety and efficacy in controlled trials; treatment effects in AML subpopulations defined by disease characteristics; experience in unselected patients treated in the community setting; clinical outcomes relative to other approved AML therapies; and experience with azacitidine-based combination treatment regimens. Collectively, these data suggest that (a) azacitidine may prolong overall survival to a similar or greater extent than do other approved AML treatments, but with less toxicity, (b) azacitidine may be the preferred treatment option for older patients with unfavorable cytogenetics, and (c) experience and outcomes with azacitidine in the clinic are similar to those seen in clinical trials. Continued investigation of combination regimens on an azacitidine backbone is warranted.

Response Rates as Predictors of Overall Survival: A Meta-Analysis of Acute Myeloid Leukemia Trials

Background: Response rates such as overall response rate (ORR), complete response (CR) and complete response with incomplete blood recovery (CRi) can be evaluated in a much shorter period of time than overall survival (OS), potentially accelerating decision making during drug development. The objective of this work was to evaluate the relationship between ORR, CR, CRi or better (CRi+CR) rates and median OS to determine whether response rates could be used as predictors of median OS in acute myeloid leukemia (AML).

Methods: A review of published literature was conducted to identify relevant AML clinical trials. Weighted linear regression was performed with various linearizing transformations of response rates and median OS. Covariates of interest were evaluated using a forward inclusion, backward elimination covariate model building procedure at α=0.01 and α=0.005, respectively.

Results: Twenty trials involving 26 cohorts were included in the meta-analysis. Azactidine treatment was a significant predictor with longer OS compared to decitabine or low dose cytarabine for a given response rate (P < 0.005). Linear regression analysis indicated that the correlation of both CRi or better rates and CR rates with median OS was higher than that of ORR with median OS. The final model showed a strong correlation between CRi or better rates and median OS (R²=0.66).

Conclusion: Significant correlation between CRi or better rates and median OS in AML highlights the potential for CRi or better rate, in addition to CR rate, to serve as surrogate markers for median OS.

A phase 1b/2b multicenter study of oral panobinostat plus azacitidine in adults with MDS, CMML or AML with ⩽30% blasts

Treatment with azacitidine (AZA), a demethylating agent, prolonged overall survival (OS) vs conventional care in patients with higher-risk myelodysplastic syndromes (MDS). As median survival with monotherapy is <2 years, novel agents are needed to improve outcomes. This phase 1b/2b trial (n=113) was designed to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D) of panobinostat (PAN)+AZA (phase 1b) and evaluate the early efficacy and safety of PAN+AZA vs AZA monotherapy (phase 2b) in patients with higher-risk MDS, chronic myelomonocytic leukemia or oligoblastic acute myeloid leukemia with <30% blasts. The MTD was not reached; the RP2D was PAN 30 mg plus AZA 75 mg/m². More patients receiving PAN+AZA achieved a composite complete response ([CR)+morphologic CR with incomplete blood count+bone marrow CR (27.5% (95% CI, 14.6–43.9%)) vs AZA (14.3% (5.4–28.5%)). However, no significant difference was observed in the 1-year OS rate (PAN+AZA, 60% (50–80%); AZA, 70% (50–80%)) or time to progression (PAN+AZA, 70% (40–90%); AZA, 70% (40–80%)). More grade 3/4 adverse events (97.4 vs 81.0%) and on-treatment deaths (13.2 vs 4.8%) occurred with PAN+AZA. Further dose or schedule optimization may improve the risk/benefit profile of this regimen.

Red blood cell alloimmunization in 184 patients with myeloid neoplasms treated with azacitidine - A retrospective single center experience

Alloimmunization to Red Blood Cell (RBC) antigens frequently occurs in patients with myeloid neoplasms (AML, MDS and CMML) and potentially poses the patient at risk for delayed hemolytic transfusion reactions and limited supply of compatible RBC-units. However, there is comparatively little data on transfusion associated characteristics in this patient cohort. We therefore retrospectively analyzed transfusion requirements and clinical outcomes of 184 patients with myloid neoplasms treated with azacitidine at the Paracelsus Medical University Salzburg, which were included in the Austrian Registry of Hypomethylating Agents. The mean blood component requirements for AML, MDS and CMML were 39.8, 67.4 and 31.4 RBC units and 31.7, 27.6 and 19.1 platelet (PLT) units respectively. In spite of an extended and stringent RBC unit matching policy (ABO, RhD, RhCcEe and K antigens), 20 (11%) patients formed at least one alloantibody ("allo-group"), whereas 164 patients (89%) did not ("non-allo-group"). The most frequent antibody specificity was anti-E, followed by anti-Wra -Lua, -D, -C and -Jka. Alloimmunization was associated with higher numbers of transfused RBC units (68 vs. 38; p=0.001), as well as with longer time under transfusion (16.7 vs. 9.4 months; p=0.014). Median overall survival (OS) did not differ significantly between the "allo"- and "non-allo-group".

Clinical Outcomes of 217 Patients with Acute Erythroleukemia According to Treatment Type and Line: A Retrospective Multinational Study

Acute erythroleukemia (AEL) is a rare disease typically associated with a poor prognosis. The median survival ranges between 3-9 months from initial diagnosis. Hypomethylating agents (HMAs) have been shown to prolong survival in patients with myelodysplastic syndromes (MDS) and AML, but there is limited data of their efficacy in AEL. We collected data from 210 AEL patients treated at 28 international sites. Overall survival (OS) and PFS were estimated using the Kaplan-Meier method and the log-rank test was used for subgroup comparisons. Survival between treatment groups was compared using the Cox proportional hazards regression model. Eighty-eight patients were treated with HMAs, 44 front line, and 122 with intensive chemotherapy (ICT). ICT led to a higher overall response rate (complete or partial) compared to first-line HMA (72% vs. 46.2%, respectively; p ≤ 0.001), but similar progression-free survival (8.0 vs. 9.4 months; p = 0.342). Overall survival was similar for ICT vs. HMAs (10.5 vs. 13.7 months; p = 0.564), but patients with high-risk cytogenetics treated with HMA first-line lived longer (7.5 for ICT vs. 13.3 months; p = 0.039). Our results support the therapeutic value of HMA in AEL.

The double-edged sword of (re)expression of genes by hypomethylating agents: from viral mimicry to exploitation as priming agents for targeted immune checkpoint modulation

Hypomethylating agents (HMAs) have been widely used over the last decade, approved for use in myelodysplastic syndrome (MDS), chronic myelomonocytic leukemia (CMML) and acute myeloid leukemia (AML). The proposed central mechanism of action of HMAs, is the reversal of aberrant methylation in tumor cells, thus reactivating CpG-island promoters and leading to (re)expression of tumor suppressor genes. Recent investigations into the mode of action of azacitidine (AZA) and decitabine (DAC) have revealed new molecular mechanisms that impinge on tumor immunity via induction of an interferon response, through activation of endogenous retroviral elements (ERVs) that are normally epigenetically silenced. Although the global demethylation of DNA by HMAs can induce anti-tumor effects, it can also upregulate the expression of inhibitory immune checkpoint receptors and their ligands, resulting in secondary resistance to HMAs. Recent studies have, however, suggested that this could be exploited to prime or (re)sensitize tumors to immune checkpoint inhibitor therapies. In recent years, immune checkpoints have been targeted by novel therapies, with the aim of (re)activating the host immune system to specifically eliminate malignant cells. Antibodies blocking checkpoint receptors have been FDA-approved for some solid tumors and a plethora of clinical trials testing these and other checkpoint inhibitors are under way. This review will discuss AZA and DAC novel mechanisms of action resulting from the re-expression of pathologically hypermethylated promoters of gene sets that are related to interferon signaling, antigen presentation and inflammation. We also review new insights into the molecular mechanisms of action of transient, low-dose HMAs on various tumor types and discuss the potential of new treatment options and combinations.

DNA methylation aberrancies as a guide for surveillance and treatment of human cancers

DNA methylation aberrancies are hallmarks of human cancers and are characterized by global DNA hypomethylation of repetitive elements and non-CpG rich regions concomitant with locus-specific DNA hypermethylation. DNA methylation changes may result in altered gene expression profiles, most notably the silencing of tumor suppressors, microRNAs, endogenous retorviruses and tumor antigens due to promoter DNA hypermethylation, as well as oncogene upregulation due to gene-body DNA hypermethylation. Here, we review DNA methylation aberrancies in human cancers, their use in cancer surveillance and the interplay between DNA methylation and histone modifications in gene regulation. We also summarize DNA methylation inhibitors and their therapeutic effects in cancer treatment. In this context, we describe the integration of DNA methylation inhibitors with conventional chemotherapies, DNA repair inhibitors and immune-based therapies, to bring the epigenome closer to its normal state and increase sensitivity to other therapeutic agents to improve patient outcome and survival.

Azacitidine Mitigates Graft-versus-Host Disease via Differential Effects on the Proliferation of T Effectors and Natural Regulatory T Cells In Vivo

Azacitidine (AzaC) mitigates graft-versus-host disease (GvHD) in both murine preclinical transplant models and in human clinical trials while maintaining a robust graft-versus-leukemia effect. Previous studies have failed to investigate the role of natural regulatory T cells (nTregs) on the mitigation of GvHD by AzaC, instead focusing on the generation of suppressive Tregs (CD4⁺CD25⁺FOXP3⁺) through the in vivo conversion of alloreactive donor T effectors (Teffs; CD4⁺CD25^-FOXP3^-) and the direct antiproliferative effects of AzaC on allogeneic T cells. Using B6.Foxp3^DTR/GFP mice in which Tregs can be specifically ablated through administration of diphtheria toxin, we demonstrate that natural Tregs are required in the donor graft for AzaC to optimally protect against GvHD and that nTregs, unlike Teffs (CD3⁺FOXP3^-), are resistant to the antiproliferative effects of AzaC. Gene expression analysis identified the potent cell cycle inhibitor, p21, was significantly upregulated in Teffs but not nTregs after treatment with AzaC. Furthermore, we demonstrate that Teffs deficient in p21 are less sensitive to the antiproliferative effects of AzaC. These results demonstrate that nTregs are essential for AzaC to fully protect against GvHD and have important clinical implications for future clinical trials testing AzaC as a novel method of GvHD prophylaxis in man.

Azacitidine or intensive chemotherapy for older patients with secondary or therapy-related acute myeloid leukemia

The treatment of older patients with acute myeloid leukemia that is secondary to previous myelodysplastic syndrome, myeloproliferative neoplasm, or prior cytotoxic exposure remains unsatisfactory. We compared 92 and 107 patients treated, respectively, with intensive chemotherapy or azacitidine within two centres. Diagnoses were 37.5% post-myelodysplastic syndrome, 17.4% post-myeloproliferative neoplasia, and 45.1% therapy-related acute myeloid leukemia. Patients treated by chemotherapy had less adverse cytogenetics, higher white blood-cell counts, and were younger: the latter two being independent factors entered into the multivariate analyses. Median overall-survival times with chemotherapy and azacitidine were 9.6 (IQR: 3.6-22.8) and 10.8 months (IQR: 4.8-26.4), respectively (p = 0.899). Adjusted time-dependent analyses showed that, before 1.6 years post-treatment, there were no differences in survival times between chemotherapy and azacitidine treatments whereas, after this time-point, patients that received chemotherapy had a lower risk of death compared to those that received azacitidine (adjusted HR 0.61, 95%CI: 0.38-0.99 at 1.6 years). There were no interactions between treatment arms and secondary acute myeloid leukemia subtypes in all multivariate analyses, indicating that the treatments had similar effects in all three subtypes. Although a comparison between chemotherapy and azacitidine remains challenging, azacitidine represents a valuable alternative to chemotherapy in older patients that have secondary acute myeloid leukemia because it provides similar midterm outcomes with less toxicity.

Azacitidine as a bridge to allogeneic hematopoietic cell transplantation in a pediatric patient with Fanconi anemia and acute myeloid leukemia

HCT is the definitive therapy for patients with FA and AML. Conventional cytotoxic agents cause potential DNA damage, and currently, there is no established regimen for these patients prior to HCT. A 13-year-old male with FA and refractory AML was given azacitidine, achieved morphologic remission and underwent HCT. At 95 days after HCT, he relapsed. Azacitidine along with DLI was used as first salvage therapy. Azacitidine was overall well tolerated with minimal side effects. In patients with AML and FA, azacitidine can be considered an alternative to conventional chemotherapy.

Azacitidine for Front-Line Therapy of Patients with AML: Reproducible Efficacy Established by Direct Comparison of International Phase 3 Trial Data with Registry Data from the Austrian Azacitidine Registry of the AGMT Study Group

We recently published a clinically-meaningful improvement in median overall survival (OS) for patients with acute myeloid leukaemia (AML), >30% bone marrow (BM) blasts and white blood cell (WBC) count ≤15 G/L, treated with front-line azacitidine versus conventional care regimens within a phase 3 clinical trial (AZA-AML-001; NCT01074047; registered: February 2010). As results obtained in clinical trials are facing increased pressure to be confirmed by real-world data, we aimed to test whether data obtained in the AZA-AML-001 trial accurately represent observations made in routine clinical practice by analysing additional AML patients treated with azacitidine front-line within the Austrian Azacitidine Registry (AAR; NCT01595295; registered: May 2012) and directly comparing patient-level data of both cohorts. We assessed the efficacy of front-line azacitidine in a total of 407 patients with newly-diagnosed AML. Firstly, we compared data from AML patients with WBC ≤ 15 G/L and >30% BM blasts included within the AZA-AML-001 trial treated with azacitidine ("AML-001" cohort; n = 214) with AAR patients meeting the same inclusion criteria ("AAR (001-like)" cohort; n = 95). The current analysis thus represents a new sub-analysis of the AML-001 trial, which is directly compared with a new sub-analysis of the AAR. Baseline characteristics, azacitidine application, response rates and OS were comparable between all patient cohorts within the trial or registry setting. Median OS was 9.9 versus 10.8 months (p = 0.616) for "AML-001" versus "AAR (001-like)" cohorts, respectively. Secondly, we pooled data from both cohorts (n = 309) and assessed the outcome. Median OS of the pooled cohorts was 10.3 (95% confidence interval: 8.7, 12.6) months, and the one-year survival rate was 45.8%. Thirdly, we compared data from AAR patients meeting AZA-AML-001 trial inclusion criteria (n = 95) versus all AAR patients with World Health Organization (WHO)-defined AML ("AAR (WHO-AML)" cohort; n = 193). Within the registry population, median OS for AAR patients meeting trial inclusion criteria versus all WHO-AML patients was 10.8 versus 11.8 months (p = 0.599), respectively. We thus tested and confirmed the efficacy of azacitidine as a front-line agent in patients with AML, >30% BM blasts and WBC ≤ 15 G/L in a routine clinical practice setting. We further show that the efficacy of azacitidine does not appear to be limited to AML patients who meet stringent clinical trial inclusion criteria, but instead appears efficacious as front-line treatment in all patients with WHO-AML.