Abstract: A retrospective analysis of 7285 cases over 2 decades. This study explores the evolution of diagnostic practices in acute myeloid leukemia patients, highlighting factors influencing test implementation and their association with patient outcomes.

Abstract: FLT3- ITD mutations are detected in approximately 25% of newly diagnosed adult acute myeloid leukemia (AML) patients and confer an adverse prognosis. The FLT3 -ITD allelic ratio has clear prognostic value. Nevertheless, there are numerous manuscripts with contradictory results regarding the prognostic relevance of the length and insertion site (IS) of the FLT3 -ITD fragment. We aimed to assess the prognostic impact of these variables on the complete remission (CR) rates, overall survival (OS) and relapse-free survival (RFS) of AML patients with  FLT3 -ITDmutations. We studied the  FLT3 -ITD length of 362 adult AML patients included in the PETHEMA AML registry. We tried to validate the thresholds of ITD length previously published (i.e., 39 bp and 70 bp) in intensively treated AML patients (n = 161). We also analyzed the mutational profile of 118 FLT3 -ITD AML patients with an NGS panel of 39 genes and correlated mutational status with the length and IS of ITD. The AUC of the ROC curve of the ITD length for OS prediction was 0.504, and no differences were found when applying any of the thresholds for OS, RFS or CR rate. Only four out of 106 patients had ITD IS in the TKD1 domain. Our results, alongside previous publications, confirm that FLT3 -ITD length lacks prognostic value and clinical applicability.

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

Abstract: Background: Options to treat elderly patients with newly diagnosed AML include intensive, attenuated chemotherapy, hypomethylating agents (HMA) and supportive care (SC). HMA have proven their efficacy in DACO-016 (NCT00260832) and AML-001 (NCT01074047) clinical trials, with a median overall survival (OS) of 7.7 months (95%CI, 6.2 to 9.2) with decitabine (DEC) vs. 5.0 months (95%CI, 4.3 to 6.3) with therapy choice (TC), considered SC or low-dose Ara-C (LDAC). Median OS was 10.4 months with azacitidine (AZA) (95%CI, 8.0 to 12.7) vs. 6.5 months (95%CI, 5.0 to 8.6) with conventional care regimens (CCR), considered standard induction chemotherapy, LDAC or SC. However, there are few direct comparative data of AZA and DEC in the context of trials or real-life settings. Aims: Here, we compared clinical outcomes between AZA and DEC in AML patients not eligible for intensive chemotherapy in the epidemiologic PETHEMA registry. Methods: We included newly diagnosed AML patients treated with AZA (75 mg/m2/d IV or SC days 1-7) or DEC (20 mg/m2/d IV days 1-5) that were not eligible for intensive chemotherapy. Responses were recorded using IWG 2003 criteria. Rates of Complete Response (CR), complete response with incomplete recovery (CRi) and OS were co-primary endpoints. Results: Between 2006 and 2019, 638 patients were included. 497 (78%) received AZA and 141 (22%) received DEC as per physician judgement. Baseline characteristics were comparable in both groups (Table 1), except for bone marrow blasts count ≥ 30%, which was more frequent in DEC group (59.2% vs 77.1%, p & lt;0.001). The CR rate was 16.3% vs 20.6% (p = 0.23); composite CR (CR+CRi) was 18.5% vs 22% (p = 0.35), and the overall response rate (ORR, partial remission (PR) plus CR+CRi) was 29.2% vs 34.8% (p=0.20); for AZA vs DEC, respectively. A significantly higher ORR to AZA was associated with ECOG & lt;2 (33.9% vs. 12.4% in patients with ECOG ≥2, OR 0.22, 95% CI 0.10 - 0.49, p=0.000), de novo AML (35.3% vs. 21.9% in secondary AML; OR 0.38, 95% CI 0.20 - 0.71, p=0.002) and estimated glomerular filtrate rate ≥ 45 mL/min/1.73m2 (30.4% vs. 9.3% in patients with estimated glomerular filtrate rate ≥ 45 mL/min/1.73m2; OR 0.15, 95% CI 0.034 - 0.67, p=0.013); while bone marrow blast count & lt; 50% was the only factor influencing ORR to DEC (43.7% vs. 25% in ≥ 50% bone marrow blasts, p=0.029). With a median follow up of 12 months, median OS was 10.0 (95% CI 8.7 - 11.2) vs 8.0 (5.7- 10.2) months for AZA vs DEC, respectively (p = 0.46) (Figure 1). Median OS was 21 (17.8 - 24.1) vs 16 (12.6 - 19.3) vs 6 months (5.0 - 7.0) for patients who achieved CR/CRi vs PR vs no response (p & lt;0.001) (Figure 2). Additional subgroup analyses by baseline characteristics performed to compare AZA vs DEC revealed that patients ≥ 80 years did benefit for treatment with AZA, median OS of 8 vs. 4 m (p=0.042), as well as patients with WBC ≥ 10 x109/L (8 vs. 5 m, p=0.036), platelet count & lt;20 x109/L (8 vs. 4 m, p=0.021) and those with estimated glomerular filtrate rate ≥ 45 mL/min/1.73m2 (10 vs. 5m, p=0.033). Conclusions: This is a large retrospective comparison with long-term follow-up of clinical outcomes associated with AZA and DEC treatment for patients with AML patients not eligible for intensive chemotherapy. There were no significant differences in ORR, CR/CRi or OS between AZA and DEC. However, patients with WBC ≥ 10 x109/L, platelet count & lt;20 x109/L and estimated glomerular filtrate rate ≥ 45 mL/min/1.73m2 could benefit from AZA in terms of OS. Disclosures Tormo: Janssen: Honoraria; Daiichi Sankyo: Honoraria; Servier: Honoraria; Roche: Membership on an entity's Board of Directors or advisory committees; Astellas: Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; MSD: Honoraria. Ramos:Amgen: Consultancy, Other: travel grant ; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: travel grant , Research Funding; Novartis: Consultancy, Other: travel grant; Takeda: Consultancy, Other: travel grant ; Daiichi-Sankyo: Other: travel grant ; Merck-Sahrp & Dohme: Other: travel grant; Rovi: Other: travel grant; Roche: Other: travel grant ; Jannsen: Other: travel grant; Abbvie: Consultancy, Other: travel grant .

Abstract: INTRODUCTION The hypomethylating agents (HMAs), decitabine (DEC) and azacitidine (AZA), are a common choice for initial treatment in elderly patients with acute myeloid leukemia (AML). However, about 60% of patients are resistant and most will relapse after a complete response (including CR/CRi). Although relapse or refractoriness to HMAs is very common, very little is known about the therapeutic management of these relapsed or refractory AML (RR-AML) patients after HMAs. METHODS We conducted a retrospective study to describe and compare salvage treatment patterns and real-life clinical outcomes of those AML patients treated upfront with AZA or DEC included in the PETHEMA-AML Registry. RESULTS Between 2006 and 2019, we included 626 AML patients treated in first-line with HMAs, 487 (78%) received AZA and 139 (22%) received DEC. Overall response rate (CR/CRi+PR) was 33.7%, 32% in the AZA vs 39.5% in the DEC group (p=0.120). Patients treated with DEC had a higher median relapse free survival than those treated with AZA (25.6 vs. 17.5 months, p=0.027). No differences were observed in the overall survival between AZA and DEC. We observed 59.7% resistance after HMAs, 60% after AZA and 58.8% after DEC; and 6.5% had other type of response ( & lt; PR), 7.9% with AZA and 1.6% with DEC. In addition, 76/121 patients who achieved CR/CRi (62.8%) relapsed, 66/90 in the AZA group (73.3%) vs 10/31 in the DEC group (32.3%) (p=0.000). After relapse or resistance, 74.5% of patients received supportive care only (BSC), which included patients receiving transfusions and other supportive measures, including oral agents to control the white blood cell counts; 71.5% of patients in the AZA group and 84.3% of patients in DEC group (p= 0.004). No differences were observed in baseline characteristics at diagnosis of patients treated with BSC only, except for a higher proportion of patients with adverse cytogenetic risk in the AZA group (46.6% vs. 33.7%, p=0.039). Only 135 patients received a salvage therapy, 116 in the AZA group and 19 in the DEC group. Thirty-five out of 135 RR-AML treated patients (26%) continued receiving HMAs: 31 (26%) in the AZA group and 4 (22%) in the DEC group. In the AZA group, 19 (16%) patients continued with AZA and 12 (10%) switched to DEC, while in the DEC group 2 patients (11%) continued with DEC and 2 (11%) switched to AZA. Fifty-one patients (37.8%) received FLUGA (fludarabine and Ara-C), FLAG-IDA-Lite (fludarabine, Ara-C and idarubicin), Low-dose Ara-C or other non-intensive regimens, 43 patients (37%) in the AZA group and 8 (42%) in the DEC group. Other salvage therapies were administered in 34% of patients (33% in the AZA group and 37% in the DEC group). Salvage therapy was not available in 1% of patients. Response assessment was available in 113/135 of RR-AML treated patients, 98 in the AZA group and 15 in the DEC group. In the AZA group, 13.2% of the patients achieved a CR (n=13), 5.1% achieved CRi (n=5), 6.1% achieved a PR (n=6), 65.3% resistance (n=64) and 8.1% died (n=8). However, no patients in the decitabine group responded to salvage therapy, 86.7% resistance (n=13) and 13.3% died (n=2). If we exclude those patients who died before response was evaluated, the ORR (CR/CRi+PR) after salvage therapy was statistically significant between AZA (n=24/90, 26.7%) and DEC group (n=0/13, 0%), p=0.035. CONCLUSIONS This study shows and compares, for the first time to our knowledge, the patterns of salvage therapy in patients with RR-AML treated upfront with HMAs. Despite the similar response rate with both HMAs, the relapse free survival was lower after AZA. The absence of responses in patients with RR-AML initially treated with DEC could justify the similar OS between AZA and DEC observed. However, we should be very cautious due to the low number of RR-AML patients treated. Disclosures de la Fuente: BMS: Consultancy, Speakers Bureau; Incyte: Consultancy, Speakers Bureau; Abbie: Consultancy, Speakers Bureau; Novartis: Research Funding. Tormo: Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jazz Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astellas: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Pérez-Simón: Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Montesinos: Forma Therapeutics: Consultancy; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Daiichi Sankyo: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Sanofi: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Stemline/Menarini: Consultancy; Teva: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Glycomimetics: Consultancy; Tolero Pharmaceutical: Consultancy; Agios: Consultancy; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Astellas Pharma, Inc.: Consultancy, Honoraria, Other: Advisory board, Research Funding, Speakers Bureau.

Abstract: This retrospective study investigated outcomes of 404 patients with relapsed/refractory (R/R) FMS-like tyrosine kinase 3 (FLT3)-internal tandem duplication (ITD) acute myeloid leukemia (AML) enrolled in the PETHEMA registry, pre-approval of tyrosine kinase inhibitors. Most patients (63%) had received first-line intensive therapy with 3 + 7. Subsequently, patients received salvage with intensive therapy (n = 261), non-intensive therapy (n = 63) or supportive care only (n = 80). Active salvage therapy (i.e., intensive or non-intensive therapy) resulted in a complete remission (CR) or CR without hematological recovery (CRi) rate of 42%. More patients achieved a CR/CRi with intensive (48%) compared with non-intensive (19%) salvage therapy (p 〈 0.001). In the overall population, median overall survival (OS) was 5.5 months; 1- and 5-year OS rates were 25% and 7%. OS was significantly (p 〈 0.001) prolonged with intensive or non-intensive salvage therapy compared with supportive therapy, and in those achieving CR/CRi versus no responders. Of 280 evaluable patients, 61 (22%) had an allogeneic stem-cell transplant after they had achieved CR/CRi. In conclusion, in this large cohort study, salvage treatment approaches for patients with FLT3-ITD mutated R/R AML were heterogeneous. Median OS was poor with both non-intensive and intensive salvage therapy, with best long-term outcomes obtained in patients who achieved CR/CRi and subsequently underwent allogeneic stem-cell transplant.

Abstract: INTRODUCTION The hypomethylating agents (HMAs), decitabine (DEC) and azacitidine (AZA), have made it possible to treat more elderly patients with acute myeloid leukemia (AML). Both HMAs have demonstrated efficacy in monotherapy and in combination with targeted therapies. However, there is little direct comparative data on AZA and DEC in first-line treatment, and we do not know which group of patients might benefit from each drug. Results of the full analysis set (FAS) were presented previously (Labrador J, et al. ASH 2020). Here, we report long-term clinical efficacy from prespecified patient subgroup analyses. METHODS We conducted a retrospective study to compare real-life clinical outcomes between AZA and DEC in patients with AML ineligible for intensive chemotherapy included in the PETHEMA registry, and analyzed clinical variables associated with response and overall survival (OS) between AZA and DEC. RESULTS A total of 626 patients were included for the FAS between 2006 and 2019. 487 (78%) received AZA and 139 (22%) received DEC. Baseline characteristics were comparable in both groups, except for the percentage of bone marrow blasts (44% vs. 34% in the DEC group compared to AZA, p=0.010). In the FAS, there was no difference in the CR, CR/CRi or ORR (CR/RCi + PR) rate: 18%, 20.5% and 32% with AZA vs. 23%, 25% and 39.5% with DEC (p=0.20, p=0.27 and p=0.12). In the subgroup analysis, DEC was associated with higher CR/CRi rate than AZA in patients with ECOG ≥ 2 (95% CI: 0.088 - 0.801), bone marrow blast count & lt; 50% (95% CI: 0.293 - 0.965), secondary AML (95% CI: 0.223 - 0.918) and adverse cytogenetics (95% CI: 0.171 - 0.857) (Figure 1A). DEC was associated with higher ORR rate than AZA in patients with ECOG ≥ 2 (95% CI: 0.116 - 0.782), leukocytes & lt; 10 x10 9/L (95% CI: 0.321 - 0.920) and bone marrow blasts & lt; 50% (95% CI: 0.321 - 0.920) (Figure 1B) 120 days-mortality was 25.4% after AZA and 27.1% after DEC, p=0.70. Patients who did not achieve at least a PR had significantly higher 120-day mortality with both HMAs (OR 8.85 and 8.22 for AZA and DEC, respectively). In the subgroup analysis, patients with leukocytes ≥ 10 x10 9/L (95% CI: 1.069 - 4.157) and those with estimated glomerular filtration rate (eGFR) ≥ 45 mL/min/1.73m 2 (95% CI: 1.249 - 4.664) had higher 120-day mortality with DEC than with AZA (Figure 1C) With a median follow-up of 12 months, median OS was 10.4 months (95% CI: 9.2 - 11.7) for AZA vs. 8.8 months (95% CI: 6.7 - 11.0) for DEC (p = 0.455). The subgroup analysis revealed that patients ≥ 80 years (95%: CI 1.005 - 2.341), with leukocytes ≥ 10 x10 9/L (95% CI 1.039 - 2.062), platelet count & lt;20 x10 9/L (95% CI: 1.150 - 3.422) and those with eGFR ≥ 45 mL/min/1.73m 2 (95% CI: 1.040 - 2.059) did benefit for treatment with AZA compared to DEC (Figure 1D). CONCLUSIONS Our study provides real-life data on the outcomes of AML patients treated with AZA compared to DEC in a large retrospective cohort with long-term follow-up. In addition, we identify for the first time some baseline characteristics that could benefit from AZA or DEC in terms of responses, 120-day mortality and OS. These findings could help us to choose the most appropriate HMA in monotherapy or for the development of new combinations. Figure 1 Figure 1. Disclosures de la Fuente: Novartis: Research Funding; Abbie: Consultancy, Speakers Bureau; Incyte: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau. Tormo: Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jazz Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astellas: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Pérez-Simón: Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Montesinos: Forma Therapeutics: Consultancy; Tolero Pharmaceutical: Consultancy; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Sanofi: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Daiichi Sankyo: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Glycomimetics: Consultancy; Agios: Consultancy; Stemline/Menarini: Consultancy; Teva: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Astellas Pharma, Inc.: Consultancy, Honoraria, Other: Advisory board, Research Funding, Speakers Bureau.