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1,667 result(s) for "Myelodysplastic Syndromes - pathology"
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Safety and tolerability of guadecitabine (SGI-110) in patients with myelodysplastic syndrome and acute myeloid leukaemia: a multicentre, randomised, dose-escalation phase 1 study
Hypomethylating agents are used to treat cancers driven by aberrant DNA methylation, but their short half-life might limit their activity, particularly in patients with less proliferative diseases. Guadecitabine (SGI-110) is a novel hypomethylating dinucleotide of decitabine and deoxyguanosine resistant to degradation by cytidine deaminase. We aimed to assess the safety and clinical activity of subcutaneously given guadecitabine in patients with acute myeloid leukaemia or myelodysplastic syndrome. In this multicentre, open-label, phase 1 study, patients from nine North American medical centres with myelodysplastic syndrome or acute myeloid leukaemia that was refractory to or had relapsed after standard treatment were randomly assigned (1:1) to receive subcutaneous guadecitabine, either once-daily for 5 consecutive days (daily × 5), or once-weekly for 3 weeks, in a 28-day treatment cycle. Patients were stratified by disease. A 3 + 3 dose-escalation design was used in which we treated patients with guadecitabine doses of 3–125 mg/m2 in separate dose-escalation cohorts. A twice-weekly treatment schedule was added to the study after a protocol amendment. The primary objective was to assess safety and tolerability of guadecitabine, determine the maximum tolerated and biologically effective dose, and identify the recommended phase 2 dose of guadecitabine. Safety analyses included all patients who received at least one dose of guadecitabine. Pharmacokinetic and pharmacodynamic analyses to determine the biologically effective dose included all patients for whom samples were available. This study is registered with ClinicalTrials.gov, number NCT01261312. Between Jan 4, 2011, and April 11, 2014, we enrolled and treated 93 patients: 35 patients with acute myeloid leukaemia and nine patients with myelodysplastic syndrome in the daily × 5 dose-escalation cohorts, 28 patients with acute myeloid leukaemia and six patients with myelodysplastic syndrome in the once-weekly dose-escalation cohorts, and 11 patients with acute myeloid leukaemia and four patients with myelodysplastic syndrome in the twice-weekly dose-escalation cohorts. The most common grade 3 or higher adverse events were febrile neutropenia (38 [41%] of 93 patients), pneumonia (27 [29%] of 93 patients), thrombocytopenia (23 [25%] of 93 patients), anaemia (23 [25%] of 93 patients), and sepsis (16 [17%] of 93 patients). The most common serious adverse events were febrile neutropenia (29 [31%] of 93 patients), pneumonia (26 [28%] of 93 patients), and sepsis (16 [17%] of 93 patients). Six of the 74 patients with acute myeloid leukaemia and six of the 19 patients with myelodysplastic syndrome had a clinical response to treatment. Two dose-limiting toxicities were noted in patients with myelodysplastic syndrome at 125 mg/m2 daily × 5, thus the maximum tolerated dose in patients with myelodysplastic syndrome was 90 mg/m2 daily × 5. The maximum tolerated dose was not reached in patients with acute myeloid leukaemia. Potent dose-related DNA demethylation occurred on the daily × 5 regimen, reaching a plateau at 60 mg/m2 (designated as the biologically effective dose). Guadecitabine given subcutaneously at 60 mg/m2 daily × 5 is well tolerated and is clinically and biologically active in patients with myelodysplastic syndrome and acute myeloid leukaemia. Guadecitabine 60 mg/m2 daily × 5 is the recommended phase 2 dose, and these findings warrant further phase 2 studies. Astex Pharmaceuticals, Stand Up To Cancer.
A phase 3 randomized, placebo-controlled study assessing the efficacy and safety of epoetin-α in anemic patients with low-risk MDS
Erythropoiesis-stimulating agents are first choice for treating anemia in low-risk MDS. This double-blind, placebo-controlled study assessed the efficacy and safety of epoetin-α in IPSS low- or intermediate-1 risk (i.e., low-risk) MDS patients with Hb ≤ 10.0 g/dL, with no or moderate RBC transfusion dependence (≤4 RBC units/8 weeks). Patients were randomized, 2:1, to receive epoetin-α 450 IU/kg/week or placebo for 24 weeks, followed by treatment extension in responders. The primary endpoint was erythroid response (ER) through Week 24. Dose adjustments were driven by weekly Hb-levels and included increases, and dose reductions/discontinuation if Hb > 12 g/dL. An independent Response Review Committee (RRC) blindly reviewed all responses, applying IWG-2006 criteria but also considering dose adjustments, drug interruptions and longer periods of observation.A total of 130 patients were randomized (85 to epoetin-α and 45 to placebo). The ER by IWG-2006 criteria was 31.8% for epoetin-α vs 4.4% for placebo (p < 0.001); after RRC review, the ER was 45.9 vs 4.4% (p < 0.001), respectively. Epoetin-α reduced RBC transfusions and increased the time-to-first-transfusion compared with placebo.Thus, epoetin-α significantly improved anemia outcomes in low-risk MDS. IWG-2006 criteria for ER may require amendments to better apply to clinical studies.
Lenalidomide with or without erythropoietin in transfusion-dependent erythropoiesis-stimulating agent-refractory lower-risk MDS without 5q deletion
After failure of erythropoiesis-stimulating agents (ESAs), lenalidomide (LEN) yields red blood cell (RBC) transfusion independence (TI) in 20-30% of lower-risk non-del5q myelodysplastic syndrome (MDS). Several observations suggest an additive effect of ESA and LEN in this situation. We performed a randomized phase III study in 131 RBC transfusion-dependent (TD, median transfusion requirement six RBC units per 8 weeks) lower-risk ESA-refractory non-del5q MDS. Patients received LEN alone, 10 mg per day, 21 days per 4 weeks (L arm) or LEN (same schedule) + erythropoietin (EPO) beta, 60,000 U per week (LE arm). In an intent-to-treat (ITT) analysis, erythroid response (HI-E, IWG 2006 criteria) after four treatment cycles (primary end point) was 23.1% (95% CI 13.5-35.2) in the L arm and 39.4% (95% CI 27.6-52.2) in the LE arm (P=0.044), while RBC-TI was reached in 13.8 and 24.2% of the patients in the L and LE arms, respectively (P=0.13). Median response duration was 18.1 and 15.1 months in the L and LE arms, respectively (P=0.47). Side effects were moderate and similar in the two arms. Low baseline serum EPO level and a G polymorphism of CRBN gene predicted HI-E. Combining LEN and EPO significantly improves erythroid response over LEN alone in lower-risk non-del5q MDS patients with anemia resistant to ESA
Rigosertib versus best supportive care for patients with high-risk myelodysplastic syndromes after failure of hypomethylating drugs (ONTIME): a randomised, controlled, phase 3 trial
Hypomethylating drugs are the standard treatment for patients with high-risk myelodysplastic syndromes. Survival is poor after failure of these drugs; there is no approved second-line therapy. We compared the overall survival of patients receiving rigosertib and best supportive care with that of patients receiving best supportive care only in patients with myelodysplastic syndromes with excess blasts after failure of azacitidine or decitabine treatment. We did this randomised controlled trial at 74 hospitals and university medical centres in the USA and Europe. We enrolled patients with diagnosis of refractory anaemia with excess blasts (RAEB)-1, RAEB-2, RAEB-t, or chronic myelomonocytic leukaemia based on local site assessment, and treatment failure with a hypomethylating drug in the past 2 years. Patients were randomly assigned (2:1) to receive rigosertib 1800 mg per 24 h via 72-h continuous intravenous infusion administered every other week or best supportive care with or without low-dose cytarabine. Randomisation was stratified by pretreatment bone marrow blast percentage. Neither patients nor investigators were masked to treatment assignment. The primary outcome was overall survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT01241500. From Dec 13, 2010, to Aug 15, 2013, we enrolled 299 patients: 199 assigned to rigosertib, 100 assigned to best supportive care. Median follow-up was 19·5 months (IQR 11·9–27·3). As of Feb 1, 2014, median overall survival was 8·2 months (95% CI 6·1–10·1) in the rigosertib group and 5·9 months (4·1–9·3) in the best supportive care group (hazard ratio 0·87, 95% CI 0·67–1·14; p=0·33). The most common grade 3 or higher adverse events were anaemia (34 [18%] of 184 patients in the rigosertib group vs seven [8%] of 91 patients in the best supportive care group), thrombocytopenia (35 [19%] vs six [7%]), neutropenia (31 [17%] vs seven [8%]), febrile neutropenia (22 [12%] vs ten [11%]), and pneumonia (22 [12%] vs ten [11%]). 41 (22%) of 184 patients in the rigosertib group and 30 (33%) of 91 patients in the best supportive care group died due to adverse events and three deaths were attributed to rigosertib treatment. Rigosertib did not significantly improve overall survival compared with best supportive care. A randomised phase 3 trial of rigosertib (NCT 02562443) is underway in specific subgroups of patients deemed to be at high risk, including patients with very high risk per the Revised International Prognostic Scoring System criteria. Onconova Therapeutics, Leukemia & Lymphoma Society.
Lenalidomide added to standard intensive treatment for older patients with AML and high-risk MDS
More effective treatment modalities are urgently needed in patients with acute myeloid leukemia (AML) of older age. We hypothesized that adding lenalidomide to intensive standard chemotherapy might improve their outcome. After establishing a safe lenalidomide, dose elderly patients with AML were randomly assigned in this randomized Phase 2 study (n = 222) to receive standard chemotherapy (“3 + 7”) with or without lenalidomide at a dose of 20 mg/day 1–21. In the second cycle, patients received cytarabine 1000 mg/m2 twice daily on days 1–6 with or without lenalidomide (20 mg/day 1–21). The CR/CRi rates in the two arms were not different (69 vs. 66%). Event-free survival (EFS) at 36 months was 19% for the standard arm versus 21% for the lenalidomide arm and overall survival (OS) 35% vs. 30%, respectively. The frequencies and grade of adverse events were not significantly different between the treatment arms. Cardiovascular toxicities were rare and equally distributed between the arms. The results of the present study show that the addition of lenalidomide to standard remission induction chemotherapy does not improve the therapeutic outcome of older AML patients. This trial is registered as number NTR2294 in The NederlandsTrial Register (www.trialregister.nl).
Age-dependent phenotypic and molecular evolution of pediatric MDS arising from GATA2 deficiency
GATA2 deficiency is an autosomal dominant transcriptopathy disorder with high risk for myelodysplastic syndrome (MDS). To elucidate genotype-phenotype associations and identify new genetic risk factors for MDS, we analyzed 218 individuals with germline heterozygous GATA2 variants. We observed striking age-dependent incidence patterns in GATA2-related MDS (GATA2-MDS), with MDS being absent in infants, rare before age 6 years, and steeply increasing in older children. Among 108 distinct GATA2 variants (67 novel), null mutations conferred a 1.7-fold increased risk for MDS, had earlier MDS onset compared to other variants (12.2 vs. 14.6 years, p  = 0.009) and were associated with lymphedema and deafness. In contrast, intron 4 variants exhibited reduced penetrance and lower risk for MDS development. Analysis of the somatic landscape revealed unique patterns of clonal hematopoiesis. SETBP1 mutations occurred exclusively in patients with monosomy 7 and their frequency decreased with age. Conversely, the frequency of STAG2 mutations and trisomy 8 increased with age and appeared protective against early development of advanced MDS. Overall, the majority (73.9%) of mutation-positive cases harbored monosomy 7, suggesting it serves as a major driver in malignant progression. Our findings provide evidence for age-appropriate surveillance, and a foundation for genotype-driven risk stratification in GATA2 deficiency.
Myelodysplastic syndromes are induced by histone methylation–altering ASXL1 mutations
Recurrent mutations in the gene encoding additional sex combs-like 1 (ASXL1) are found in various hematologic malignancies and associated with poor prognosis. In particular, ASXL1 mutations are common in patients with hematologic malignancies associated with myelodysplasia, including myelodysplastic syndromes (MDSs), and chronic myelomonocytic leukemia. Although loss-of-function ASXL1 mutations promote myeloid transformation, a large subset of ASXL1 mutations is thought to result in stable truncation of ASXL1. Here we demonstrate that C-terminal–truncating Asxl1 mutations (ASXL1-MTs) inhibited myeloid differentiation and induced MDS-like disease in mice. ASXL1-MT mice displayed features of human-associated MDS, including multi-lineage myelodysplasia, pancytopenia, and occasional progression to overt leukemia. ASXL1-MT resulted in derepression of homeobox A9 (Hoxa9) and microRNA-125a (miR-125a) expression through inhibition of polycomb repressive complex 2–mediated (PRC2-mediated) methylation of histone H3K27. miR-125a reduced expression of C-type lectin domain family 5, member a (Clec5a), which is involved in myeloid differentiation. In addition, HOXA9 expression was high in MDS patients with ASXL1-MT, while CLEC5A expression was generally low. Thus, ASXL1-MT–induced MDS-like disease in mice is associated with derepression of Hoxa9 and miR-125a and with Clec5a dysregulation. Our data provide evidence for an axis of MDS pathogenesis that implicates both ASXL1 mutations and miR-125a as therapeutic targets in MDS.
Synergistic induction of PI-PLCβ1 signaling by azacitidine and valproic acid in high-risk myelodysplastic syndromes
The association between azacitidine (AZA) and valproic acid (VPA) has shown high response rates in high-risk myelodysplastic syndromes (MDS) cases with unfavorable prognosis. However, little is known about the molecular mechanisms underlying this therapy, and molecular markers useful to monitor the disease and the effect of the treatment are needed. Phosphoinositide-phospholipase C (PI-PLC) β1 is involved in both genetic and epigenetic mechanisms of MDS progression to acute myeloid leukemia. Indeed, AZA as a single agent was able to induce PI-PLCβ1 expression, therefore providing a promising new tool in the evaluation of response to demethylating therapies. In this study, we assessed the efficacy of the combination of AZA and VPA on inducing PI-PLCβ1 expression in high-risk MDS patients. Furthermore, we observed an increase in Cyclin D3 expression, a downstream target of PI-PLCβ1 signaling, therefore suggesting a potential combined activity of AZA and VPA in high-risk MDS in activating PI-PLCβ1 signaling, thus affecting cell proliferation and differentiation. Taken together, our findings might open up new lines of investigations aiming at evaluating the role of the activation of PI-PLCβ1 signaling in the epigenetic therapy, which may also lead to the identification of innovative targets for the epigenetic therapy of high-risk MDS.
TP53 mutation status divides myelodysplastic syndromes with complex karyotypes into distinct prognostic subgroups
Risk stratification is critical in the care of patients with myelodysplastic syndromes (MDS). Approximately 10% have a complex karyotype (CK), defined as more than two cytogenetic abnormalities, which is a highly adverse prognostic marker. However, CK-MDS can carry a wide range of chromosomal abnormalities and somatic mutations. To refine risk stratification of CK-MDS patients, we examined data from 359 CK-MDS patients shared by the International Working Group for MDS. Mutations were underrepresented with the exception of TP53 mutations, identified in 55% of patients. TP53 mutated patients had even fewer co-mutated genes but were enriched for the del(5q) chromosomal abnormality (p < 0.005), monosomal karyotype (p < 0.001), and high complexity, defined as more than 4 cytogenetic abnormalities (p < 0.001). Monosomal karyotype, high complexity, and TP53 mutation were individually associated with shorter overall survival, but monosomal status was not significant in a multivariable model. Multivariable survival modeling identified severe anemia (hemoglobin < 8.0 g/dL), NRAS mutation, SF3B1 mutation, TP53 mutation, elevated blast percentage (>10%), abnormal 3q, abnormal 9, and monosomy 7 as having the greatest survival risk. The poor risk associated with CK-MDS is driven by its association with prognostically adverse TP53 mutations and can be refined by considering clinical and karyotype features.
Myelodysplastic syndrome progression to acute myeloid leukemia at the stem cell level
Myelodysplastic syndromes (MDS) frequently progress to acute myeloid leukemia (AML); however, the cells leading to malignant transformation have not been directly elucidated. As progression of MDS to AML in humans provides a biological system to determine the cellular origins and mechanisms of neoplastic transformation, we studied highly fractionated stem cell populations in longitudinal samples of patients with MDS who progressed to AML. Targeted deep sequencing combined with single-cell sequencing of sorted cell populations revealed that stem cells at the MDS stage, including immunophenotypically and functionally defined pre-MDS stem cells (pre-MDS-SC), had a significantly higher subclonal complexity compared to blast cells and contained a large number of aging-related variants. Single-cell targeted resequencing of highly fractionated stem cells revealed a pattern of nonlinear, parallel clonal evolution, with distinct subclones within pre-MDS-SC and MDS-SC contributing to generation of MDS blasts or progression to AML, respectively. Furthermore, phenotypically aberrant stem cell clones expanded during transformation and stem cell subclones that were not detectable in MDS blasts became dominant upon AML progression. These results reveal a crucial role of diverse stem cell compartments during MDS progression to AML and have implications for current bulk cell–focused precision oncology approaches, both in MDS and possibly other cancers that evolve from premalignant conditions, that may miss pre-existing rare aberrant stem cells that drive disease progression and leukemic transformation.