Outcome of older (≥70 years) APL patients frontline treated with or without arsenic trioxide-an International Collaborative Study

Data on outcome in older (≥70 years) patients with acute promyelocytic leukemia after treatment with arsenic trioxide (ATO) compared with standard chemotherapy (CTX) is scarce. We evaluated 433 patients (median age, 73.4 years) treated either with ATO+ all-trans retinoic acid (ATO/ATRA; n = 26), CTX/ATRA + ATO during consolidation (CTX/ATRA/ATO; n = 148), or with CTX/ATRA (n = 259). Median follow-up for overall survival (OS) was 4.8 years. Complete remissions (CR) were achieved in 92% with ATO/ATRA and 82% with CTX/ATRA; induction death rates were 8% and 18%, respectively. For analysis of postremission outcomes we combined the ATO/ATRA and CTX/ATRA/ATO groups (ATO/ATRA ± CTX). Cumulative incidence of relapse (CIR) was significantly lower after ATO/ATRA ± CTX compared with CTX/ATRA (P 10 × 10 9 /l) white blood cell (WBC) counts at diagnosis were associated with higher CIR (P < 0.001) compared with lower WBC in the CTX/ATRA group, but not in the ATO/ATRA ± CTX group (P = 0.48). ATO, when added to ATRA or CTX/ATRA is feasible and effective in elderly patients for remission induction and consolidation, particularly in patients with high WBC at diagnosis

Synergistic effects of PRIMA-1Met (APR-246) and 5-azacitidine in TP53-mutated myelodysplastic syndromes and acute myeloid leukemia

Myelodysplastic syndromes and acute myeloid leukemia with TP53 mutations are characterized by frequent relapses, poor or short responses, and poor survival with the currently available therapies including chemotherapy and 5-azacitidine (AZA). PRIMA-1Met(APR-246,APR) is a methylated derivative of PRIMA-1, which induces apoptosis in human tumor cells through restoration of the transcriptional transactivation function of mutant p53. Here we show that low doses of APR on its own or in combination with AZA reactivate the p53 pathway and induce an apoptosis program. Functionally, we demonstrate that APR exerts these activities on its own and that it synergizes with AZA in TP53-mutated myelodysplastic syndromes (MDS)/acute myeloid leukemia (AML) cell lines and in TP53-mutated primary cells from MDS/AML patients. Low doses of APR on its own or in combination with AZA also show significant efficacy in vivo. Lastly, using transcriptomic analysis, we found that the APR + AZA synergy was mediated by downregulation of the FLT3 pathway in drug-treated cells. Activation of the FLT3 pathway by FLT3 ligand reversed the inhibition of cell proliferation by APR + AZA. These data suggest that TP53-mutated MDS/AML may be better targeted by the addition of APR-246 to conventional treatments

Arsenic: Une thérapie de choix dans la leucémie aiguë promyélocytaire avec mutation FLT3-ITD

International audienc

TP53 Alterations in Myelodysplastic Syndromes and Acute Myeloid Leukemia

TP53 mutations are less frequent in myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) than in solid tumors, except in secondary and therapy-related MDS/AMLs, and in cases with complex monosomal karyotype. As in solid tumors, missense mutations predominate, with the same hotspot mutated codons (particularly codons 175, 248, 273). As TP53-mutated MDS/AMLs are generally associated with complex chromosomal abnormalities, it is not always clear when TP53 mutations occur in the pathophysiological process. It is also uncertain in these MDS/AML cases, which often have inactivation of both TP53 alleles, if the missense mutation is only deleterious through the absence of a functional p53 protein, or through a potential dominant-negative effect, or finally a gain-of-function effect of mutant p53, as demonstrated in some solid tumors. Understanding when TP53 mutations occur in the disease course and how they are deleterious would help to design new treatments for those patients who generally show poor response to all therapeutic approaches

Outcome of older (≥70 years) APL patients frontline treated with or without arsenic trioxide—an International Collaborative Study

Leucèmia mieloide aguda; Genètica clínicaLeucemia mieloide aguda; Genética clínicaAcute myeloid leukaemia; Clinical geneticsData on outcome in older (≥70 years) patients with acute promyelocytic leukemia after treatment with arsenic trioxide (ATO) compared with standard chemotherapy (CTX) is scarce. We evaluated 433 patients (median age, 73.4 years) treated either with ATO+ all-trans retinoic acid (ATO/ATRA; n = 26), CTX/ATRA + ATO during consolidation (CTX/ATRA/ATO; n = 148), or with CTX/ATRA (n = 259). Median follow-up for overall survival (OS) was 4.8 years. Complete remissions (CR) were achieved in 92% with ATO/ATRA and 82% with CTX/ATRA; induction death rates were 8% and 18%, respectively. For analysis of postremission outcomes we combined the ATO/ATRA and CTX/ATRA/ATO groups (ATO/ATRA ± CTX). Cumulative incidence of relapse (CIR) was significantly lower after ATO/ATRA ± CTX compared with CTX/ATRA (P 10 × 109/l) white blood cell (WBC) counts at diagnosis were associated with higher CIR (P < 0.001) compared with lower WBC in the CTX/ATRA group, but not in the ATO/ATRA ± CTX group (P = 0.48). ATO, when added to ATRA or CTX/ATRA is feasible and effective in elderly patients for remission induction and consolidation, particularly in patients with high WBC at diagnosis.Open Access funding enabled and organized by Projekt DEAL

FLT3-ITD impedes retinoic acid, but not arsenic, responses in murine acute promyelocytic leukemias.

Acute promyelocytic leukemia (APL) is often associated with activating FLT3 signaling mutations. These are highly related to hyperleukocytosis, a major adverse risk factor with chemotherapy-based regimens. APL is a model for oncogene-targeted therapies: all-trans retinoic acid (ATRA) and arsenic both target and degrade its ProMyelocytic Leukemia/Retinoic Acid Receptor α (PML/RARA) driver. The combined ATRA/arsenic regimen now cures virtually all patients with standard-risk APL. Although FLT3-internal tandem duplication (ITD) was an adverse risk factor for historical ATRA/chemotherapy regimens, the molecular bases for this effect remain unknown. Using mouse APL models, we unexpectedly demonstrate that FLT3-ITD severely blunts ATRA response. Remarkably, although the transcriptional output of initial ATRA response is unaffected, ATRA-induced PML/RARA degradation is blunted, as is PML nuclear body reformation and activation of P53 signaling. Critically, the combination of ATRA and arsenic fully rescues therapeutic response in FLT3-ITD APLs, restoring PML/RARA degradation, PML nuclear body reformation, P53 activation, and APL eradication. Moreover, arsenic targeting of normal PML also contributes to APL response in vivo. These unexpected results explain the less favorable outcome of FLT3-ITD APLs with ATRA-based regimens, and stress the key role of PML nuclear bodies in APL eradication by the ATRA/arsenic combination

Long-Term Real-World Experience of CPX-351 in Combined French-Italian Cohorts Identified High Rate of Negative Measurable Residual Disease (MRD) and Prolonged Overall Survival

International audienceIntroduction CPX-351 is a liposomal formulation of cytarabine and daunorubicin packaged at a 5:1 molar ratio. This drug has been approved by the FDA and EMEA for patients with therapy-related acute myeloid leukemia (t-AML) or AML with myelodysplasia-related changes (MRC-AML) according to the WHO 2016 AML classification. Real world experience from several countries (France, Italy, Germany, UK and US) showed similar results of phase 3 clinical registration but with short follow-up. Lancet et al. published a long-term update of phase 3 clinical trial and confirmed long-term remission and improvement of overall survival (OS) ( Lancet Haematology 2021). Thus, the primary objective of this study was to analyze the efficacy of CPX-351 in a real-life setting with a longer follow-up, evaluating the impact of measurable residual disease (MRD) in responding patients. Methods We retrospectively collected data from patients treated with CPX-351 in thirty-six centers in France and Italy. Overall response rate (ORR) was defined by complete remission (CR) and CR with incomplete hematological recovery (CRi). Among the patients in CR or CRi, 62 (61%) had MRD evaluation assessed by next-generation sequencing (NGS) or flow cytometry. OS was calculated from the date of AML diagnosis to the date of death or last follow-up. All statistical analysis were performed using SPSS v.22 software (IBM SPSS Statistics). Results Between April 2018 and October 2019, 170 patients treated with CPX-351 were included in this study. The sex ratio male/female was 80/90 and the median age was 66 years (range 20-83). AML subtypes were MRC-AML in 117 (69%) and t-AML 48 (28%) patients. According to the European LeukemiaNet (ELN) 2017 classification, genetic risk was favorable, intermediate, and adverse in 8 (5%), 61 (36%), and 98 (58%) (missing for 3 patients), respectively. According to the ELN 2022 classification, genetic risk was favorable, intermediate, and adverse in 8 (5%), 16 (9%) and 143 (84%), respectively. Thirty percent and 19% of patients had complex and monosomal karyotypes, respectively. Assessed by NGS the most frequent mutated genes were: TP53 (n=35, 21%), RUNX1 (n=30, 18%), ASXL1 (n=22, 13%) and TET2 (n=18, 11%) among the XX were NGS was available (sinon ca fait des % qui ne tombe pas juste sur les 170 pts). According to a genetic ontogeny-based classifier (Lindsley et al., Blood 2015), 28 %, 39% and 33% had de novo/pan-AML, secondary type mutations AML, and TP53 mutated AML, respectively. The ORR was 102/170 (60%) after one (n=91) or two (n=11) inductions including 53% CR and 6% CRi. Among the 102 CR/CRi patients, 62 (61%) were evaluable for MRD after induction or after first consolidation. Forty (65%) patients had MRD below the threshold of 10 -3. ELN2017 and ELN2022 were identified as factors predicting CR/CRi rate ( P=0.032 and P=0.043, respectivelyà but the Lindsley classifier did not predict response ( P= 0.060). After 3-years of follow-up, in a univariate analysis, only MRD &gt;10 -3 ( P=0.031); ELN 2017 classification ( P=0.027) and presence of TP53 mutation ( P=0.017) but not ELN 2022 or the Lindsley classifier; were associated with a significantly poorer median OS. In a multivariate analysis, only MRD &gt;10 -3 was associated with a poorer OS (hazard ratio [HR]=2.6, 95% CI 1.2-5.5, P=0.013). Median OS was 40.9 months vs. 10.6 months for patients with MRD &lt;10 -3 vs. ≥10 -3, respectively ( P=0.006). Sixty (35%) patients underwent an allogeneic hematopoietic stem cell transplant (HSCT) with an improved median OS compared to non-transplanted patients (not-reached vs. 9.1 months, P&lt;0.0001). We also observed a trend towards a better median OS in transplanted patients who underwent an HSCT with MRD &lt;10 -3 (not reached vs. 26.0 months, P=0.06). Conclusion After 3 years of follow-up, the improved OS with CPX-351 was confirmed in the real- life setting. Achievement of MRD negativity contributed to improvement of OS in the overall population and, maybe, in transplanted patients. These data provide the rationale for the ongoing ALFA-2101 phase III clinical trial evaluating CPX-351 vs. 3+7 (daunorubicin and cytarabine) in non-MRC-AML and non-t-AML using MRD as the primary endpoint