Azacitidine has limited activity in 'real life' patients with MDS and AML: a single centre experience

Analysis of 5-Azacytidine Resistance Models Reveals a Set of Targetable Pathways

The mechanisms by which myelodysplastic syndrome (MDS) cells resist the effects of hypomethylating agents (HMA) are currently the subject of intensive research. A better understanding of mechanisms by which the MDS cell becomes to tolerate HMA and progresses to acute myeloid leukemia (AML) requires the development of new cellular models. From MDS/AML cell lines we developed a model of 5-azacytidine (AZA) resistance whose stability was validated by a transplantation approach into immunocompromised mice. When investigating mRNA expression and DNA variants of the AZA resistant phenotype we observed deregulation of several cancer-related pathways including the phosphatidylinosito-3 kinase signaling. We have further shown that these pathways can be modulated by specific inhibitors that, while blocking the proliferation of AZA resistant cells, are unable to increase their sensitivity to AZA. Our data reveal a set of molecular mechanisms that can be targeted to expand therapeutic options during progression on AZA therapy.

The Impact of the Epigenetic Cancer Drug Azacitidine on Host Immunity: The Role of Myelosuppression, Iron Overload and tp53 Mutations in a Zebrafish Model

The unsatisfactory real-world efficacy of the hypomethylating agent azacitidine in treating myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) has prompted us to investigate the hematological adverse events and host variables that may compromise the use of this epigenetic drug. Using the zebrafish, we found that azacitidine destroyed their myeloid precursors and impaired myeloid function by inhibiting antigen processing, allogeneic response and phagocytic activity, resulting in increased susceptibility to infection even by the normal flora E. coli. In addition, iron overload, a MDS-associated condition following repeated transfusions, exacerbated bacterial infection especially by V. vulnificus with known iron dependence. Furthermore, we show that the tp53^M214K mutant zebrafish survived longer than the wild-type (WT) when challenged with bacteria following azacitidine treatment. This was attributed to the mutant’s hematopoietic cells rather than its general genetic background, since the WT animals reconstituted with the tp53^M214K mutant kidney marrow became more resistant to bacterial infection following treatment with azacitidine. The clinical relevance of our findings was indicated by a MDS case with severe azacitidine-induced bone marrow suppression and by the association of hyperferritinemia with bacteremia in azacitidine-treated patients, while tp53^M214K-mediated resistance to azacitidine-induced myelosuppression may explain the survival advantage of malignant MDS and AML clones over their normal counterparts under azacitidine treatment. Together, we propose that myelosuppression, iron overload and TP53 mutations may represent the host variables that compromise the azacitidine efficacy.

Treatment patterns and comparative analysis of non-intensive regimens in elderly acute myeloid leukemia patients-a real-world experience from India

Elderly patients with acute myeloid leukemia have a poor prognosis. Data from developing countries is sparse in the literature. In this retrospective study, 402 patients aged ≥ 60 years, diagnosed between Jan 2013 and Dec 2017, were analyzed for treatment patterns and survival. Median age of the whole cohort was 68 years (range 61-84). A total of 213 patients (53.3%) refused care; 188 patients (46.7%) received either BSC, LDAC, or HMA. Survival (in months) was 3.9, 6.4, and 1.2 with LDAC, HMA, and BSC, respectively. One-year survival was 17.2% and 6% with HMA and LDAC, respectively (P = 0.02). Overall response rate (ORR) did not differ between HMA and LDAC group (p = 0.12). HMA cohort had higher complete responses (20.6% vs 7.4%, p = 0.02), stable disease (32.7% vs 13.5%, p = 0.02), and transfusion independence (TI) (46.5% vs 22.2%, p = 0.01). Survival did not differ between the groups if the patients achieved ORR (12.3 vs 9.8 p = 0.2) or TI (11.6 vs 6.4 p = 0.2). Stable disease with HMA led to longer survival (8.1 vs 5.3 p = 0.01). HMAs were more effective than LDAC irrespective of cytogenetic risk category and blasts, of note HMAs improved survival of poor risk patients (5.6 vs 2.9 p = 0.004). HMA treatment (HR = 0.48; 95% 0.29-0.79, p = 0.004) and transfusion independence (HR = 0.2; 95% 0.1-0.3, p = 0.0001) predicted survival in multivariate analysis. Neutropenia and febrile neutropenia were frequent in HMA. Thrombocytopenia was the common adverse event with LDAC. Novel and cost-effective drugs are essential to improve the prognosis of these patients.

Real Life Data on Efficacy and Safety of Azacitidine Therapy for Myelodysplastic Syndrome, Chronic Myelomonocytic Leukemia and Acute Myeloid Leukemia

The administration of azacitidine (AZA) was found to be more effective than conventional care regimen (CCR) in patients with higher-risk myelodysplastic syndromes (MDS), chronic myelomonocytic leukemia (CMML) and acute myeloid leukemia (AML) with lower blast count. We designed a study to determine efficacy and safety of AZA therapy in “real life” patients with MDS, CMML and AML. The study included 83 patients (65% male) with a median age at diagnosis of 68 years. 43 patients were diagnosed with higher-risk MDS, 30 had AML and 10-CMML. Median AZA dose was comparable between treated groups. AZA dose reduction was required for 44% of MDS, 17% of AML and 25% of CMML patients. Complete remission (CR) was achieved in 14% of MDS, 7% of AML and 10% of CMML patients. Overall response rate was following: 27% for MDS, 20% for AML and 20% for CMML. Estimated OS at 12 months was 75% for MDS, 60% for AML and 75% for CMML. Median follow-up for MDS/AML/CMML from AZA initiation to last follow-up was 9.0, 9.4 and 9.4 months, respectively. The most common toxicity of AZA therapy was myelosuppression and infections. AZA treatment was effective in a limited number of patients with acceptable safety profile.

Integrated bioinformatic analysis of microarray data reveals shared gene signature between MDS and AML

Myeloid disorders, especially myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), cause significant mobility and high mortality worldwide. Despite numerous attempts, the common molecular events underlying the development of MDS and AML remain to be established. In the present study, 18 microarray datasets were selected, and a meta-analysis was conducted to identify shared gene signatures and biological processes between MDS and AML. Using NetworkAnalyst, 191 upregulated and 139 downregulated genes were identified in MDS and AML, among which, PTH2R, TEC, and GPX1 were the most upregulated genes, while MME, RAG1, and CD79B were mostly downregulated. Comprehensive functional enrichment analyses revealed oncogenic signaling related pathway, fibroblast growth factor receptor (FGFR) and immune response related events, 'interleukine-6/interferon signaling pathway, and B cell receptor signaling pathway', were the most upregulated and downregulated biological processes, respectively. Network based meta-analysis ascertained that HSP90AA1 and CUL1 were the most important hub genes. Interestingly, our study has largely clarified the link between MDS and AML in terms of potential pathways, and genetic markers, which shed light on the molecular mechanisms underlying the development and transition of MDS and AML, and facilitate the understanding of novel diagnostic, therapeutic and prognostic biomarkers.

Myelodysplastic syndromes current treatment algorithm 2018

Myelodysplastic syndromes (MDS) include a group of clonal myeloid neoplasms characterized by cytopenias due to ineffective hematopoiesis, abnormal blood and marrow cell morphology, and a risk of clonal evolution and progression to acute myeloid leukemia (AML). Because outcomes for patients with MDS are heterogeneous, individual risk stratification using tools such as the revised International Prognostic Scoring System (IPSS-R) is important in managing patients-including selecting candidates for allogeneic hematopoietic stem cell transplantation (ASCT), the only potentially curative therapy for MDS. The IPSS-R can be supplemented by molecular genetic testing, since certain gene mutations such as TP53 influence risk independent of established clinicopathological variables. For lower risk patients with symptomatic anemia, treatment with erythropoiesis-stimulating agents (ESAs) or lenalidomide (especially for those with deletion of chromosome 5q) can ameliorate symptoms. Some lower risk patients may be candidates for immunosuppressive therapy, thrombopoiesis-stimulating agents, or a DNA hypomethylating agent (HMA; azacitidine or decitabine). Among higher risk patients, transplant candidates should undergo ASCT as soon as possible, with HMAs useful as a bridge to transplant. Non-transplant candidates should initiate HMA therapy and continue if tolerated until disease progression. Supportive care with transfusions and antimicrobial drugs as needed remains important in all groups.

Systematic review of azacitidine regimens in myelodysplastic syndrome and acute myeloid leukemia

Background

5-Azacitidine administered as a 7-day dosing regimen (7–0-0) is approved in high risk IPSS myelodysplastic syndrome (MDS) patients. Alternative regimens such as a 5-day (5–0-0) or 7-day with a weekend break (5–2-2) are commonly used. No randomized controlled trial has been done directly comparing all three dosing regimens. The objective of this study was to compare the efficacies of the 5–0-0, 5–2-2, and 7–0-0 regimens in MDS and AML.

Methods

A systematic review was conducted using MEDLINE, EMBASE and CENTRAL. Eligible studies were randomized controlled trials (RCTs), observational prospective and retrospective studies. The primary clinical outcomes were Objective Response Rate (ORR) defined as the sum of complete response (CR), partial response (PR), and hematological improvement (HI) as defined by the IWG 2006 criteria. A meta-analysis of simple proportions was conducted using a random effects model with weights defined according to Laird and Mosteller. Comparisons between groups were not attempted due to the heterogeneity of study designs.

Results

The only RCT directly comparing alternative azacitidine regimens showed no difference in ORR between the 5–0-0 and 5–2-2 regimens. All other RCTs compared a dosing regimen to conventional care. The pooled proportion of ORR was 44.8% with 95% CI (42.8%, 45.5%) for 7–0-0, 41.2% with 95% CI (39.2%, 41.9%) for 5–0-0, and 45.8% with 95% CI (42.6%, 46.4%) for 5–2-2.

Conclusions

Indirect comparison of alternative azacitidine dosing regimens in MDS and AML shows a benefit for the 7-day regimen in attaining ORR. Additional RCTs are required to definitively address this comparison.

Electronic supplementary material

The online version of this article (10.1186/s12878-017-0094-8) contains supplementary material, which is available to authorized users.

Treatment with 5-Azacytidine improves clinical outcome in high-risk MDS patients in the 'real life' setting: A single center observational study

OBJECTIVES

The demethylating factor 5-Azacytidine (5-AZA) improves survival of patients with myelodysplastic syndromes (MDS) in randomized control trials but the results in 'real life' are controversial.

METHODS

In this retrospective study, we evaluated the outcome of 56 high-risk MDS patients who were treated with 5-AZA between 2005 and 2013. 5-AZA was administered in an outpatient basis at a dose 75 mg/m(2) s.c. with the following schedule: 5 days on/weekend off/2 days on (5/2/2).

RESULTS

The overall response rate (ORR) was 50%; 21.2% patients achieved complete response (CR), 3.8% partial response (PR), and 25% hematologic improvement (HI); 34.6% had stable disease (SD) and 15.4% showed progressive disease (PD). The estimated median event free survival (EFS) and overall survival (OS) were 11 and 17 months, respectively. Interestingly, the estimated time to acute myeloid leukemia transformation was 30 months, which refers to patients who responded to AZA treatment or remained stable. Patients who responded to the 5-AZA achieving CR, PR, and HI had better EFS and OS compared to the patients who had SD or PD. In addition, Δ WHO Classification-based Prognostic Score System (ΔWPSS), which represents the improvement of WPSS risk group before and after treatment, was associated with significantly improved OS and better EFS. Finally, the response to treatment was not associated with the expression of p53.

CONCLUSIONS

In conclusion, 5-AZA is an effective treatment for high-risk MDS. Improved OS and EFS were found mainly in patients who responded to the treatment while ΔWPSS seems to represent a promising future prognostic tool.

Safety and efficacy of azacitidine in Belgian patients with high-risk myelodysplastic syndromes, acute myeloid leukaemia, or chronic myelomonocytic leukaemia: results of a real-life, non-interventional post-marketing survey

OBJECTIVES

We evaluated azacitidine (Vidaza(®)) safety and efficacy in patients with myelodysplastic syndrome (MDS), acute myeloid leukaemia (AML), and chronic myelomonocytic leukaemia (CMML), in a real-life setting. Treatment response, dose, and schedule were assessed.

METHODS

This non-interventional, post-marketing survey included 49/50 patients receiving azacitidine at 14 Belgian haematology centres from 2010-2012. Treatment-emergent adverse events (TEAEs), including treatment-related TEAEs, and serious TEAEs (TESAEs) were recorded throughout the study. Treatment response [complete response (CR), partial response (PR), haematological improvement (HI), stable disease (SD), treatment failure (TF)) and transfusion-independence (TI) were evaluated at completion of a 1-year observation period (1YOP) or at treatment discontinuation, and overall survival (OS), at study conclusion.

RESULTS

The median age of patients was 74·7 (range: 43·9-87·8) years; 69·4% had MDS, 26·5% had primary or secondary AML, and 4·1% had CMML. Treatment-related TEAEs, grade 3-4 TEAEs, and TESAEs were reported in 67·3%, 28·6%, and 18·4% of patients, respectively. During 1YOP, patients received a median of 7 (1-12) treatment cycles. Treatment response was assessed for 38/49 patients. Among MDS and CMML patients (n = 29), 41·4% had CR, PR, or HI, 41·4% had SD, and 17·2% had TF. Among AML patients (n = 9), 44·4% had CR or PR, 33·3% had SD, and 22·2% had TF. TI was observed in 14/32 (43·8%) patients who were transfusion-dependent at baseline. Median (95% confidence interval) OS was 490 (326-555) days; 1-year OS estimate was 0·571 (0·422-0·696).

CONCLUSIONS

Our data support previous findings that azacitidine has a clinically acceptable safety profile and shows efficacy.

Azacitidine for myelodysplastic patients aged > 65 years: a review of clinical efficacy

INTRODUCTION

Therapeutic strategies for elderly patients affected by myelodysplastic syndromes (MDS) are scarce and only few patients have an advantage in performing allogeneic bone marrow transplant.

AREAS COVERED

Primary endpoints for treatment of elderly MDS patients were not curative, but rather allowing to maintain a good quality of life through prolongation of overall survival. In this context, azacitidine showed to improve responses in this subset of patients compared to conventional established regimens, such as intensive or low-dose chemotherapy and best supportive care. Good safety profile of the drug was reported either when it was used inside or outside clinical trials. Improved quality of response was observed when the drug was administered beyond the first response, and it is now usually recommended to continue it at the same dose and schedule in responding patients.

EXPERT OPINION

Evaluation of baseline prognostic factors and comorbidities may help to identify patients who can benefit from the prolonged administration of the drug. Real life data regarding efficacy and safety of azacitidine in MDS elderly patients are required in order to confirm the results of clinical trials.

EZH2 in normal and malignant hematopoiesis

The histone methyltransferase Enhancer of Zeste Homologue 2 (EZH2), a component of the polycomb group complex, is vital for stem cell development, including hematopoiesis. Its primary function, to deposit the histone mark H3K27me3, promotes transcriptional repression. The activity of EZH2 influences cell fate regulation, namely the balance between self-renewal and differentiation. The contribution of aberrant EZH2 expression to tumorigenesis by directing cells toward a cancer stem cell (CSC) state is increasingly recognized. However, its role in hematological malignancies is complex. Point mutations, resulting in gain-of-function, and inactivating mutations, reported in lymphoma and leukemia, respectively, suggest that EZH2 may serve a dual purpose as an oncogene and tumor-suppressor gene. The reduction of CSC self-renewal via EZH2 inhibition offers a potentially attractive therapeutic approach to counter the aberrant activation found in lymphoma and leukemia. The discovery of small molecules that specifically inhibit EZH2 raises the exciting possibility of exploiting the oncogenic addiction of tumor cells toward this protein. However, interference with the tumor-suppressor role of wild-type EZH2 must be avoided. This review examines the role of EZH2 in normal and malignant hematopoiesis and recent developments in harnessing the therapeutic potential of EZH2 inhibition.

Efficacy of the hypomethylating agents as frontline, salvage, or consolidation therapy in adults with acute myeloid leukemia (AML)

The hypomethylating agents (HAs), azacitidine and decitabine, have emerged as an alternative to initial and salvage therapy in patients with acute myeloid leukemia (AML). Little is known about how AML responds to hypomethylating agents after standard therapy, and the activity of these agents in a real-world setting is not well studied. We retrospectively examined data for 75 consecutive AML patients at Wake Forest from 2002 to 2011 treated with HAs either as first-line (n = 34), salvage (n = 28), or consolidation (n = 13) therapy. We collected data on age, gender, race, Charlson comorbidity index (CCI), cytogenetics, type of treatment, complete remission (CR), complete remission with incomplete count recovery (CRi), and survival. Statistical analysis was performed using Kaplan-Meier estimates and Cox proportional hazards models. Frontline response rate (CR + CRi) was 26.5 %, and median overall survival (OS) was 3.4 months (95 % CI 1.3-7.4), with 18 % alive at 1 year. In the salvage cohort, the response rate was significantly lower compared to frontline (3.6 versus 26.5 %, p = 0.017). Despite the reduced response, OS from time of HA treatment was longer than frontline at 8.2 months (CI 4.8-10.3). In the consolidation cohort, OS was 13.8 months (CI 8.0-21.6) with one patient in remission more than 30 months from diagnosis. These data suggest that prior cytotoxic therapy decreases marrow response rates to HAs but not survival. Furthermore, use of hypomethylating agents for consolidation resulted in a median overall survival over 1 year in a cohort of older patients. This suggests that hypomethylating agents have activity in all phases of AML treatment.

Physician's Attitude Towards Treatment of Older Patients and the Choice of Therapy

The treatment of acute myeloid leukemia in older patients is still object of controversies, because of considerable heterogeneity among patients and different characteristics in the disease. Reluctance in administering conventional intensive chemotherapy relies on life-threatening complications induced by treatment in an often frail patient population. Nonetheless, while there is general consensus on the management of frail patients with supportive care only, a wide area of uncertainty remains for a considerable proportion of patients in whom treatment beyond support is feasible, with the aim of altering the natural history of the disease. Several predictive score have been proposed in order to prevent toxicity in absence of survival advantage; however in the daily practice patients' and physician attitude does still play a major role in the final therapeutic decision.

Conventional chemotherapy or hypomethylating agents for older patients with acute myeloid leukaemia?

Acute myeloid leukaemia (AML) is the second more frequent hematologic malignancy in developed countries and primarily affects older adults with a median age at diagnosis of 69 years. Given the progressive ageing of the general population, the incidence of the disease in elderly people is expected to further increase in the years to come. Along with cytogenetics at diagnosis, age represents the most relevant prognostic factor in AML, in that the outcome steadily declines with increasing age. Reasons for poor prognosis include more frequent unfavourable karyotype and other adverse biologic characteristics, such as high rates of expression of genes drug resistance related and high prevalence of secondary AML. Noticeably, as compared with young adults, poorer results in elderly patients have been reported within any cytogenetic and molecular prognostic subgroup, because of frequent comorbid diseases, which render many patients ineligible to intensive chemotherapy. Therefore, predictive models have been developed with the aim of achieving best therapeutic results avoiding unnecessary toxicity. Following conventional induction therapy, older AML patients have complete remission rates in the range of 45-65%, and fewer than 10% of them survive for a minimum of 5 years. On the other hand, hypomethylating agents, such as azacytidine and decitabine offer the possibility of long-term disease control without necessarily achieving complete remission and can represent a reasonable alternative to intensive chemotherapy. Either intensive chemotherapy or hypomethylating agents have lights and shadows, and the therapeutic selection is often influenced by physician's and patient's attitude rather than definite criteria. Research is progress in order to assess predictive biologic factors, which would help clinicians in the selection of patients who can take actual benefit from different therapeutic options.

Can hypomethylating agents provide a platform for curative therapy in myelodysplastic syndromes?

The hypomethylating agents (HMAs) azacitidine and decitabine have changed the treatment landscape of myelodysplastic syndromes (MDS) since their approval by the United States Food and Drug Administration (US FDA) in 2004 and 2006, respectively. However, neither agent is able to cure patients with MDS, and when patients fail to respond to treatment with these agents, their prognosis is poor. For this reason, investigators are currently testing combination regimens with an HMA as a backbone and altering the dose, schedule, and method of delivery of HMAs. Additionally, more than 30 new molecules are currently being tested in interventional studies for which patients with MDS are eligible to enroll. These efforts may further improve outcomes for patients with MDS. For the time being, allogeneic stem cell transplantation (ASCT) remains patients' only real opportunity for cure and should be performed whenever possible in patients with higher-risk disease.