ELN Risk Research Articles

Does size matter? Center-specific characteristics and survival after allogeneic hematopoietic cell transplantation for acute myeloid leukemia: an analysis of the German Registry for Stem Cell Transplantation and Cell Therapy.

We investigated the effect of center-specific variables on overall survival (OS) after allogeneic hematopoietic cell transplantation (alloHCT) in acute myeloid leukemia (AML). Eligible were adult patients reported to DRST registry receiving first alloHCT for AML from a related or matched (>= 9/10 HLA-match) unrelated donor 2015-2021. Primary endpoint was OS at 12 months from alloHCT. Univariable and multivariable analyses after best subset selection was performed. Of 5328 patients, 83% received alloHCT in a high-volume center (≥40 alloHCT/year); 90% in a university hospital; 90% in a center performing alloHCT for ≥10 years; and 73% in a Joint Accreditation Committee IHCT-Europe and EBMT (JACIE) accredited center. 52% of the patients were in CR1, and ELN risk was adverse in 37% and intermediate in 42%. On multivariable analysis, center-specific factors predicting adverse 12-month OS were program duration.

The Proteasome-Family-Members-Based Prognostic Model Improves the Risk Classification for Adult Acute Myeloid Leukemia.

Background: The accumulation of diverse molecular and cytogenetic variations contributes to the heterogeneity of acute myeloid leukemia (AML), a cluster of hematologic malignancies that necessitates enhanced risk evaluation for prognostic prediction and therapeutic guidance. The ubiquitin-proteasome system plays a crucial role in AML; however, the specific contributions of 49 core proteasome family members (PSMs) in this context remain largely unexplored. Methods: The expression and survival significance of 49 PSMs in AML were evaluated using the data from BeatAML2.0, TCGA, and the GEO database, mainly through the K-M plots, differential genes enrichment analysis, and candidate compounds screening via R language and statistical software. Results: we employed LASSO and Cox regression analyses and developed a model comprising three PSMs (PSMB8, PSMG1, and PSMG4) aimed at predicting OS in adult AML patients, utilizing expression profiles from the BeatAML2.0 training datasets. Patients with higher risk scores were predominantly found in the AML-M2 subtype, exhibited poorer ELN stratification, showed no complete remission following induction therapies, and had a higher mortality status. Consistently, significantly worse OS was observed in high-risk patients across both the training and three validation datasets, underscoring the robust predictive capability of the three-PSMs model for AML outcomes. This model elucidated the distinct genetic abnormalities landscape between high- and low-risk groups and enhanced the ELN risk stratification system. Ultimately, the three-PSMs risk score captured AML-specific gene expression signatures, providing a molecular basis for selecting potential therapeutic agents. Conclusions: In summary, these findings manifested the significant potential of the PSM model for predicting AML survival and informed treatment strategies.

The clinical implications of BCOR mutations in a large cohort of acute myeloid leukemia patients: a 5-year single-center retrospective study

To elucidate the effect of BCOR mutation (BCOR mut) on clinical outcomes, we included a total of 899 consecutive AML patients in a single-center during July 2016 to December 2021. Fifty cases (5.6%) had BCOR mutations, which co-occurred with mutations of RUNX1, DNMT3A, IDH2, BCORL1, STAG2, SF3B1 and U2AF1, but were exclusive with KIT and CEBPA mutations. BCOR mut was also found to be exclusive with t(8;21)(q22;q22.1) AML in all patients and MLL rearrangements in the European Leukemia Net (ELN) adverse group. In those receiving intensive chemotherapy regimens, BCOR mut was associated with lower complete remission (CR) rates and worse prognosis. Subgroup analysis showed that BCOR mut mainly conferred a poor prognosis in the intermediate and adverse groups of the ELN2017 risk. These results suggest that BCOR mutation is an independent prognostic parameter in AML, implying BCOR mutation as a novel marker for chemorefractory disease and inferior prognosis.

Gemtuzumab Ozogamicin and Stem Cell Mobilization for Autologous Stem Cell Transplantation in Favorable Risk Acute Myeloid Leukemia.

Gemtuzumab ozogamicin (GO), a CD33-targeting antibody drug conjugate, previously showed longer relapse-free survival when combined with induction chemotherapy in patients with favorable-risk acute myeloid leukemia (AML). In this patient population, characterized by lower relapse risk as compared to other ELN risk groups, autologous stem cell transplantation (ASCT) can be used as consolidation strategy. However, there are limited data on the impact of GO on the peripheral blood stem cell (PBSC) mobilization potential. We therefore retrospectively analyzed data from 54 AML patients with favorable-risk AML treated with (n = 17) or without (n = 37) GO during induction treatment. We observed no significant differences in the PBSC mobilization rate between patients treated with vs. without GO. The mobilization success in a first attempt directly following cycle 2 was 65% vs. 70% (p = 0.92); and the mobilization success in a subsequent second attempt after hematologic recovery and repeated stimulation procedure was 24% vs. 19% (p = 0.56). No significant impact on treatment outcome in terms of EFS (p = 0.31) or OS (p = 0.99) was observed. Thus, our results suggest that the addition of GO to induction regimens does not negatively impact PBSC mobilization in favorable-risk AML patients. To our best knowledge, this is the first study comparing the stem cell mobilization potential in favorable-risk AML patients treated with vs. without GO.

KRAS mutations in patients with AML: clinical characteristics and not reported mutations using NGS

ABSTRACT Background AML is a complex and heterogeneous disease. The KRAS gene is one of the important genes in the pathogenesis of acute myeloid leukemia (AML). Mutant RAS can promote oncogenesis via different mechanisms including oncogenic transcription, cell cycle progression, cellular survival, growth, metabolism, and cell migration. Therefore, it is important to identify the genomic landscape of AML. The aim of the study is to identify KRAS variants in AML and their association with clinic pathological criteria and possible effects on prognosis using NGS. Method Hotspot mutations in the KRAS gene were studied using Ion S5 next-generation sequencing system. Bone marrow samples of newly diagnosed AML patients were collected to identify hotspot mutations in the KRAS gene. DNA amplicons were subjected to sequencing and were analyzed using ion torrent software. Patients were classified according to the FAB classification system. Patients are also classified according to the cytogenetic groups and the ELN risk stratification system. Results KRAS mutations were detected in exon 2, 3, whereas no mutations in KRAS exon 1. Interestingly, Novel mutations were detected in KRAS in AML Egyptian patients. Also, there was no statistically significant association of RAS mutations with different clinical and prognostic parameters. However, KRAS mutant patients tended to have increased PB WBC counts, percentage of PB, and bone marrow blasts. Conclusion NGS is considered a useful tool to identify KRAS variants that could be useful for risk stratification and tailored therapy in AML patients

Impact of body mass index and karyotype on clinical outcomes in adolescents and young adults (AYA) with acute myeloid leukemia.

6551 Background: Acute myelogenous leukemia (AML) represents 15%–20% of leukemias in children and approximately 33% in adolescents and young adults (AYA) (1). Obesity has been associated with worse outcome in acute lymphoblastic leukemia in AYA patients (pts). To date, however, the relationship between weight and clinical outcomes in AYA pts diagnosed with AML has not been established. We investigated the impact of body mass index (BMI) along with other prognostic factors on outcomes of AYA AML pts receiving intensive chemotherapy and/or allogeneic stem cell transplant (SCT). Methods: This retrospective chart review included pts 18-39 yrs newly diagnosed with AML between 01/2006-12/2023. All pts received intensive chemotherapy with cytarabine- and anthracycline-based induction followed by consolidation chemotherapy +/- SCT. BMI was calculated using height and weight at AML diagnosis. Pts were classified by BMI into under, normal, overweight, or obese categories. AML risk classification (ELN 2022) and HCT co-morbidity index (HCT-CI) were performed. Outcomes included complete response (CR), CR with incomplete counts (CRi), overall response rates (CR+CRi), event free survival (EFS), and overall survival (OS). Results: Eighty-seven pts (median age 25 yrs, range 18-38) were identified. 44 (51%) were male; 85% were Caucasian. Per ELN 2022, 27 (31%) had favorable, 40 (46%) intermediate, and 20 (23%) adverse risk. Overall response rate to chemotherapy was 92% (CR 80%, CRi 12%). CR rate by ELN was 96%, 72% and 58%, respectively. Median OS for all pts was 788 days and per ELN risk was 1379, 569, and 595 days, respectively. Co-morbidity indices (HCT-CI) ranged from 0-5. Sixty-two percent underwent SCT. 29% relapsed. The percentage of pts alive at 2 and 5 years was 54% and 29%. Pts were categorized by BMI: underweight (BMI < 18.5, 6%), normal weight (NW) (BMI 18.5-24.9) (37%), overweight (OW)(BMI 25-29, 26%), and obese (OB) (BMI > 30, 31%) pts. Overall, there was a trend to improved outcomes in NW vs OW and OB pts. Median OS was 1006 (NW) vs 748 (OW) vs 678 (OB) days (p=0.0036 for NW vs OW/OB). Two-year OS was 63%, 52%, and 48%; 5-year OS was 38%, 26%, and 19%. The impact of BMI was dependent on AML karyotype. In favorable risk AML AYA pts, the relapse rate was 4%, 4% and 12%. Median OS was 1982 (NW), 1169 (OW), and 1256 (OB) days (p=0.0525 NW vs OW/OB). Five-year OS was 50%, 25% and 18%. The most common causes of death were GVHD-induced multi-organ failure and respiratory failure which did not correlate with HCT-CI. In intermediate and adverse risk AML, there was no difference in outcomes by BMI. Conclusions: Outcomes of favorable risk AYA AML pts following intensive chemotherapy +/- SCT was influenced by BMI with increased mortality and shorter OS in pts with high BMI (overweight and obese) as compared to normal BMI. Additional studies to confirm this finding and elucidate the underlying reasons are warranted.

FLAG-IDA + venetoclax in newly diagnosed (ND) or relapsed/refractory (RR) AML.

6519 Background: We report the outcomes of a phase 2 study of FLAG-IDA+VEN in AML. Methods: Pts ≥18 with ND or RR AML / MDS-EB2 fit for intensive chemotherapy were eligible. Induction comprised fludarabine 30mg/m2 D2–6, cytarabine 1.5g/m2 D2–6, idarubicin 8 (6 if RR) mg/m2 D4–6 & filgrastim 5mcg/kg D1–7. VEN 400mg was administered D1–14 with CYP3A inhibitor dose adjustment until Jul 2023; following a protocol modification, VEN is now administered D1–7. The primary outcome was ORR (CR + CRh + CRi + MLFS + PR). Secondary outcomes were CRc (CR + CRh + CRi), overall survival (OS), event-free survival (EFS) & duration of response (DOR). Measurable residual disease (MRD) was assessed by flow cytometry. Results: As of Jan 2024, 134 pts have enrolled, 127 (68 ND & 59 RR) evaluable at data cut. Median age was 45 (18 – 73); 19 (15%) age ≥60. 13 (19%), 22 (32%) & 33 (49%) ND pts were ELN22 favorable, intermediate & adverse respectively. There were 7 (10%) secondary (s), including 4 hypomethylating agent failure, & 7 (10%) therapy-related (t) AML. In RR pts, 40 (68%) were in salvage 1 (S1), of whom 32 (54%) were TP53WT. 20 (34%) had prior stem cell transplant (SCT). Median of 2 cycles were given. In ND pts, ORR was 99%, (96% CRc, of whom 89% MRD negative [Table]). Similar responses were seen across ELN groups & s/tAML. At median follow-up (mFU) of 30 months (mo), the mOS, mEFS & mDOR were not reached. The 2yr OS, EFS & DOR were 75% (64 – 88), 68% (56 – 81) & 71% (59 – 85) respectively, with no differences among ELN groups. 57% went to SCT in CR1. 4/4 pts with TP53mut became CRc MRD–, but mDOR was only 8.2 mo (95% CI, 2.2 – NE), resulting in poor mOS (13.5 mo, 95% CI, 8.6 – NE). In RR pts, ORR was 70% (66% CRc, of whom 79% MRD negative [Table]). At mFU 27 mo, the mOS, mEFS & mDOR were 12 (7 – 33), 7 (4 – 23) & 21 (8 – NE) mo respectively. The 2yr OS, EFS & DOR were 40% (28 – 55), 34% (23 – 49) & 49% (35 – 68) respectively. 58% went to SCT. S1+ TP53WT pts had mOS of 34 mo (12 – NE), with 72% going to SCT. 30d & 60d mortality were 0% & 3%. Of the 4 deaths within 60d, 1 was sepsis-related in CR in a ND pt while 3 were disease-related in NR RR pts. The most frequent adverse event was infection. Grade ≥3 infections, gastrointestinal toxicities & bleeding occurred in 102 (80%), 20 (16%) & 9 (7%) pts respectively. The median time to neutrophil >1x109/L & platelet >50x109/L were 27d & 28d for C1, 39d & 67d for C2 & 35d & 50d for C3 respectively. Conclusions: FLAG-IDA+VEN results in high MRD negative response rates, leading to impressive survival outcomes across ELN risk groups in ND AML. It is an effective salvage regimen for RR AML, especially for S1+ TP53WT pts. Clinical trial information: NCT03214562 . [Table: see text]

A chest CT-based nomogram for predicting survival in acute myeloid leukemia

BackgroundThe identification of survival predictors is crucial for early intervention to improve outcome in acute myeloid leukemia (AML). This study aim to identify chest computed tomography (CT)-derived features to predict prognosis for acute myeloid leukemia (AML).Methods952 patients with pathologically-confirmed AML were retrospectively enrolled between 2010 and 2020. CT-derived features (including body composition and subcutaneous fat features), were obtained from the initial chest CT images and were used to build models to predict the prognosis. A CT-derived MSF nomogram was constructed using multivariate Cox regression incorporating CT-based features. The performance of the prediction models was assessed with discrimination, calibration, decision curves and improvements.ResultsThree CT-derived features, including myosarcopenia, spleen_CTV, and SF_CTV (MSF) were identified as the independent predictors for prognosis in AML (P < 0.01). A CT-MSF nomogram showed a performance with AUCs of 0.717, 0.794, 0.796 and 0.792 for predicting the 1-, 2-, 3-, and 5-year overall survival (OS) probabilities in the validation cohort, which were significantly higher than the ELN risk model. Moreover, a new MSN stratification system (MSF nomogram plus ELN risk model) could stratify patients into new high, intermediate and low risk group. Patients with high MSN risk may benefit from intensive treatment (P = 0.0011).ConclusionsIn summary, the chest CT-MSF nomogram, integrating myosarcopenia, spleen_CTV, and SF_CTV features, could be used to predict prognosis of AML.

Abstract 5184: Biomarker results from PEVENAZA, a randomized phase 2 study of venetoclax and azacitidine +/- pevonedistat in newly diagnosed AML patients unfit for intensive chemotherapy: Increased efficacy in a subset of patients with IDH1/2 mutations and other observations

Abstract Background: Many newly diagnosed patients with AML are ineligible for intensive chemotherapy due to pre-existing comorbidities and older age. VIALE-A, a phase-3 trial with venetoclax (ven) and azacitidine (aza) established this combination as a new standard of care (SOC) for this patient population. The addition of pevonedistat (pevo) to this combination was evaluated in the same patient population in the current trial (NCT04266795). Here we present results of biomarker analyses from baseline and on-treatment bone marrow samples. Methods: Molecular mutational analysis was performed using a next generation sequencing (NGS) panel on baseline bone marrow samples. Combining this data with cytogenetics allowed centralized assignment of risk category based on ELN2017 guidelines. Longitudinal bone marrow aspirate samples were also examined by multi-color flow cytometry for expression of select surface antigen expression and to identify AML leukemic stem cells (LSCs) from the blast population. Results: Eleven genes were selected for analyses based on prevalence and scientific interest, including DNMT3A, ASXL1, TET2, FLT3, and IDH1/2. In contrast to other genes and ELN risk categories, we observed a statistically significant increase (p-value 0.013) in CR+CRi rates for IDH1/2 mutant patients when treated with pevo + ven + aza (95%, n=21) compared to ven+aza control arm (62%, n=21). In addition, we evaluated the prevalence of CD33, CD123 and CLEC12a, targets of current AML developmental therapeutics, in both the blast and LSC populations at baseline. The median (n=120 pts) % blast cells expressing CD33, CD123, or CLEC12a were 89.8%, 63.2%, and 66.0%, respectively. The median (n=78 pts) % LSCs expressing CD33, CD123, or CLEC12a were 48.2%, 90.9%, and 32.0%, respectively. Importantly, we did not see any significant difference in median fluorescence intensity (MFI) or % expression in any of the three proteins after treatment with ven and aza (+/- pevo). Finally, no strong associations were observed between expression levels and either mutations or ELN risk categories. Conclusions: Analyses of biomarker samples as part of the PEVENAZA trial resulted in several insights for not only the pevonedistat program but also for other AML therapeutics in development. The observation that newly diagnosed patients with IDH1/2 mutations may benefit from the addition of pevo to ven+aza is certainly hypothesis-generating but would require further follow-up with higher patient numbers. In addition, baseline CD33, CD123, and CLEC12a expression levels were in line with published studies. Here we have also shown they remain similar after SOC treatment (ven+aza) supporting the development of agents that target these proteins in both first and second line settings for AML. Citation Format: Radha Ramesh, Xiang Fang, Shuli Li, Sharon Friedlander, Farhad Sedarati, Lionel Adès, Nicholas Short, Cristina Papayannidis, Tammie Yeh. Biomarker results from PEVENAZA, a randomized phase 2 study of venetoclax and azacitidine +/- pevonedistat in newly diagnosed AML patients unfit for intensive chemotherapy: Increased efficacy in a subset of patients with IDH1/2 mutations and other observations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5184.

Clinical and genetic characteristics predict outcomes of acute myeloid leukemia patients with FLT3 mutations receiving venetoclax-based therapy.

Acute myeloid leukemia (AML) is a heterogeneous disease, and its heterogeneity is associated with treatment response. Despite the demonstrated success of venetoclax (VEN)-based therapy for AML, the effect of FLT3 mutations on the efficacy of the therapy is poorly understood. We aimed to compare the efficacy of VEN-based therapy between FLT3-mutated (FLT3mut ) and FLT3 wild-type (FLT3wt ) patients and identify the predictors of efficacy in FLT3mut patients. A total of 266 AML patients (127 newly diagnosed [ND] and 139 refractory/relapsed [R/R]) receiving VEN-based regimens were enrolled in this study. A retrospective analysis was performed, and the treatment responses and overall survival (OS) of FLT3mut and FLT3wt patients were compared. Logistic regression and Cox proportional hazards model were applied to examine the clinical and genetic predictors of outcomes. With a median of two cycles of VEN-based therapy, for the ND AML cohort, the FLT3mut group had a comparable composite complete remission (CRc) rate with the FLT3wt group (79.3% vs. 61.2%, p = 0.072). For the R/R AML cohort, the FLT3mut group exhibited a lower CRc rate than the FLT3wt group. With a median follow-up of 8.6 months (95% confidence interval [CI], 8.0-10), the median OS observed in the FLT3mut and FLT3wt groups for both cohorts were close (14.0 vs. 19.9 months, p = 0.356; 10.0 vs. 11.9 months, p = 0.680). For the ND AML cohort, in FLT3mut patients, MRD-positive and RNA-splicing mutation predicted inferior survival (hazard ratio [HR], 10.3; 95% CI: 2.0-53.8; p = 0.006; HR 11.3; 95% CI: 1.2-109.3; p = 0.036, respectively). For the R/R AML cohort, in FLT3mut patients, adverse ELN risk was associated with an inferior response (odds ratio [OR], 0.2; 95% CI: 0.1-0.8; p = 0.025), whereas NPM1 co-mutation was associated with a superior response (57.1%; OR, 6.7; 95% CI: 1.5-30.1; p = 0.014). CR/CRi predicted a better survival (HR 0.2; 95% CI: 0.1-0.8; p = 0.029), while DNMT3A mutation predicted an inferior survival (HR, 4.6; 95% CI: 1.4-14.9; p = 0.011). FLT3 mutations may influence response to VEN-based therapy in R/R AML patients but not in ND AML patients. Furthermore, clinical and genetic characteristics could predict outcomes of FLT3mut patients receiving VEN-based therapy.

Venetoclax: A Game Changer in the Treatment of Younger AML Patients?

The combination approach based on venetoclax (VEN) with azacytidine (AZA) has significantly improved outcomes for elderly patients with acute myeloid leukemia (AML). This innovative approach has led to higher rates of overall response, measurable residual disease (MRD)-negative remissions, and overall survival compared with AZA monotherapy. As a result, this combination has emerged as the gold-standard treatment for elderly or unfit patients with AML who are not eligible for intensive therapy. In younger, fit patients with AML, intensive induction and consolidation chemotherapy is commonly used as a first-line approach; however, relapse continues to be the main reason for treatment failure in approximately 30-40% of patients. Efforts to improve MRD-negative response rates and to facilitate the transition to allogeneic hematopoietic stem cell transplantation, particularly in high-risk AML, have inspired trials exploring the combination of intensive chemotherapy with targeted agents. VEN, a first-in-class anti-BCL2 agent, combined with intensive chemotherapy regimens has shown deep MRD-negative remissions, producing prolonged event-free survival and enhancing the transition to allogeneic transplant in first-complete-remission patients. These benefits support the incremental advantages of adding VEN to intensive chemotherapy approaches across ELN risk subcategories, and provides a robust benchmark to design future trials. In this review, we will discuss current studies assessing the efficacy of frontline regimens integrating VEN into intensive chemotherapy in younger patients with AML and specific molecularly defined subgroups.

Reduced duration and dosage of venetoclax is efficient in newly diagnosed patients with acute myeloid leukemia

ABSTRACT Objectives The combination of Venetoclax (VEN) and Azacitidine (AZA) increases survival outcomes and yields excellent responses in patients with acute myeloid leukemia (AML). However, dose reduction (or discontinuation) is commonly encountered due to therapy-related toxicity. Thus, this study aimed to investigate the efficiency and safety of a lower dosage of venetoclax for the treatment of AML. Methods This observational study analyzed the characteristics and outcomes of newly diagnosed AML patients who received 100 mg VEN combined with AZA for 14 days at our institution. Results A total of 36 patients were enrolled, and the median age at diagnosis was 64 years. After a median follow-up of 15 (range 4–29) months, the median overall survival (OS) and progression-free survival (PFS) for the whole cohort were 17 (4–29) months and 12 (1–28) months, respectively. Meanwhile, the overall response rate (ORR) was 69.4%, and the CRc rate was 66.7% in the whole cohort. Subgroup analysis revealed that NPM1 mutations and FAB-M5 subtype were associated with higher response rates, whereas the adverse ELN risk group was predictive of an inferior response. Moreover, ASXL1, NPM1, and IDH1/2 mutations negatively impacted PFS. Discussion Our study optimized the administration of venetoclax plus azacytidine for the treatment of AML patients. Response rates were favorable, with median survival in agreement with the findings of earlier reports, offering valuable insights for optimizing VEN-based regimens. Conclusion In summary, the VEN combination regimen is effective for the treatment of newly diagnosed AML patients in the real world despite VEN dose reductions .

Prognostic significance of the frequencies of bone marrow lymphocyte subsets in adult acute myeloid leukemia at diagnosis.

Immune microenvironment plays an important role in the occurrence and development of acute myeloid leukemia (AML). Studies assessing the prognostic significance of bone marrow (BM) lymphocyte subsets' frequencies at diagnosis in patients with AML were limited. Fresh BM samples collected from 97 adult AML patients at diagnosis were tested for lymphocyte, T, CD4+ T, CD8+ T, γδT, NK, and B cell frequencies using multi-parameter flow cytometry. Low frequencies of lymphocytes, T, CD4+ T, and CD8+ T cells were associated with significantly lower rates of one-course complete remission (CR) (all p < 0.05). Moreover, the frequency of CD4+ T cells independently predicted one-course CR achievement (p = 0.021). Low frequencies of T and CD8+ T cells were significantly associated with lower relapse-free survival (RFS) rates (p = 0.032; 0.034), respectively, and a low frequency of CD8+ T cells was associated with a significantly lower overall survival (OS) rate (p = 0.028). Combination of frequency of CD8+ T cells and ELN risk stratification showed that patients with ELN-intermediate/adverse risk + high CD8+ T cell frequency had a similar RFS rate to those with ELN-favorable risk + high CD8+ T cell frequency and those with ELN-favorable risk + low CD8+ T cell frequency (p = 0.88; 0.76), respectively. The RFS rate of patients with ELN intermediate/adverse risk + low CD8+ T cell frequency was significantly lower than that of all aforementioned patients (p = 0.021; 0.0007; 0.028), respectively. The frequencies of BM lymphocyte subsets at diagnosis predicted clinical outcomes and could help improve risk stratification in AML.

Venetoclax in Combination with Intermediate Doses of Cytarabine in Consolidation Phase for Acute Myeloid Leukemia Patients in First Complete Remission; Results of the Part 1 of the Phase 1/2 Multicentric Covenidac Study

For authors: Please: L Gastaud and P Peterlin: co-primary, H dombret et C Recher: co-last Background: The French ALFA-FILO AML intergroup launched the BIG-1 trial (EudraCT No.: 2014-000699-24) in 2015 to evaluate different intensive chemotherapy (ICT) strategies aiming at improving the survival of younger adults with acute myeloid leukemia (AML). All patients (pts) with previously untreated non-APL and non-CBF AML aged 18-60 years were eligible for this trial. The trial design included several randomization types. Results of the R1 and R2 randomizations, namely idarubicin vs daunorubicin for induction and IDAC vs HDAC for consolidation, will be reported at this meeting. In patients who achieved first complete remission (CR), randomizations R4 consisted of nested randomized Phase 2 or 1/2 studies evaluating the addition of new drugs to the IDAC/HDAC consolidation cycles. The protocol was designed to allow several sequential multicenter R4 evaluations of various new agents over the trial period. Venetoclax (VEN) has proved its efficacy when combined to azacitidine or low dose cytarabine in unfit AML pts (DiNardo et al. 2020; Wei et al. Blood 2020). Its role in fit patients treated with ICT is still under investigation. The COVENIDAC Phase 1/2 R4 sub-study is evaluating the safety and efficacy of VEN added to IDAC during the consolidation cycles of CR pts. We report herein the result of the Phase 1 part. Methods: The primary objective of this Phase 1 study was to determine the maximum tolerated dose (MTD) of VEN in combination with IDAC during the consolidation cycles, which will be the recommended dose for the Phase 2 (RP2D). Dose limiting toxicities (DLTs) were assessed during the first cycle of consolidation (C1) according to a 3+3 design. A maximum of 3 consolidation cycles was planned depending on the AML risk group. Hematological DLT was defined as no peripheral blood count recovery within 56 days from day 1 of the cycle. Non-hematological DLTs were defined as Grade ≥4 toxicities or Grade ≤3 toxicities which have not recovery by day 56 and deemed related to VEN per investigator opinion. VEN was started at dose level (DL) 1: 100 mg/d from day 1 to 8. In the absence of DLTs at DL1, 3 others DL were planned: 200 mg/d from day 1 to 8 (DL2); 400 mg/d from day 1 to 8 (DL3), and 400 mg/d from day 1 to 14 (DL4). IDAC was administrated at 1.5 gr/m² twice daily on day 1/3/5 for DL1, DL2 and DL3 pts, then on day 1/2/3 for DL4 pts after a protocol amendment. Main inclusion criteria were: pts in first CR following 1 or 2 courses of induction chemotherapy fit for further ICT; favorable and intermediate risk AML as defined by the protocol; ECOG PS ≤2; written informed consent. Measurable residual disease (MRD) was assessed by multiparametric flow cytometry (MFC) in all pts as well as NPM1-qPCR in NPM1-mutated pts. Results: Between 06/2021 and 04/2022, 15 pts from 9 centers were screened and enrolled. Pt characteristics were as follows: median age, 42 years (IQR, 30-49); 2 males/7 females; ECOG-PS, 0 in 10 pts and 1 in 5 pts; favorable/intermediate/adverse ELN-2017 risk, 9/2/4. Neutropenia and thrombocytopenia durations are shown in Table 1. Only 1 hematological DLT was observed at DL3 (platelet count of 96 giga/L at day 56 in a patient who was infected by Covid-19). Overall, there were very few non hematological AEs ( Table 2, no grade 4) and only 4 SAEs (1 related to IDAC/VEN during C1, 3 non-related). No non-hematological DLT was observed. No patient died during the DLT observation period, 1 experienced a septic shock (C2, DL2). One pt received only C1 (due to DLT), 7 received 2 cycles, and 7 received 3 cycles. Median time between initiation of subsequent consolidation cycles was 37.5 days (IQR, 35-41) for C1/C2 and 40 days (IQR, 35-43) for C2/C3. One pt had to stop VEN during C3. Six pts received an allogeneic HSCT (5 in CR1, 1 after salvage). With a median follow-up of 13.5 months, 3 pts relapsed and 2 died. MRD results will be presented. Conclusion: VEN/IDAC combination appears to be feasible and safe as consolidation therapy, with expected thrombocytopenia and neutropenia durations. These durations appeared even shorter at DL4, when IDAC was given on 3 consecutive days. VEN at 400 mg/d from day 1 to 14 combined with IDAC on day 1/2/3 was thus retained as RP2D for the randomized Phase 2 with RFS as primary endpoint. This phase 2 has already recruited 29 of the 200 pts planned.

Applicability of SIE/Sies/GITMO Fitness Criteria to Therapy-Related and AML-MRC Receiving CPX-351: Results from a Large, Retrospective, Multicentric, Observational Study

Introduction: Treatment of therapy-related AML (t-AML) and AML evolving from an antecedent myelodysplastic syndrome (AML-MRC) represent a clinical unmet need being characterized by an unfavorable outcome. Among the emerging treatment options, CPX-351 has been approved by Regulatory Authorities for the treatment of fit patients (pts) affected by these AML sub-types. Although patented for the treatment of pts fit for intensive chemotherapy, in real-life CPX-351 is also administered to unfit ones, raising the case of tolerability in these categories. Among scores for fitness definition, SIE/SIES/GITMO criteria were extensively validated in large cohorts of AML pts receiving intensive chemotherapy and are increasingly incorporated into clinical trials. However, since these criteria have not been tested yet in the subset of t-AML and AML-MRC, we investigated their applicability in these pts receiving CPX-351. Methods: Patients classified as t-AML or MRC-AML according to WHO2016 classification receiving at least one cycle of CPX-351 were included in the present analysis. Genetic and cytogenetic data were classified according to ELN2017 risk stratification. SIE/SIES/GITMO criteria were retrospectively applied to the whole series to categorize pts as fit or unfit to intensive chemotherapy (Ferrara et. al, Leukemia 2013), aiming at evaluating early-death rate and overall survival (OS). We also verified if ELN2017 risk-stratification might provide further information about long-term outcome, independently of fitness assessment. Results: This retrospective study includes 398 pts with t-AML (19.3%) or AML-MRC (80.7%) enrolled from 29 Italian Institutions between 2018 and 2023. Median age was 65 years (range 32-79), with a slight male prevalence (56.8%). According to SIE/SIES/GITMO criteria, 323 (81.2%) pts qualified as fit and 75 (18.8%) as unfit. Based on ELN2017 risk stratification, 17 (4.3%) pts were classified as favorable, 162 (40.7%) as intermediate, 217 (54.5%) as adverse risk. Only 2 (0.5%) pts were not classifiable due to incomplete genetic data. No differences were observed in terms of ELN2017 risk distribution among the fit and unfit groups. After first induction, 188 of 323 (58.2%) fit and 42 of 75 (56%) unfit pts achieved a complete remission (CR), for a total of 230 (57.8%) pts entering CR. From CPX-351 start, 18 and 55 deaths at 28 days and at 100 days occurred, respectively. Early death rate at these early timepoints statistically differed between the two groups (3% vs. 10.7% at 28 days and 10% vs. 28% at 100 days for fit and unfit pts respectively; p&amp;lt;0.05). No excess of mortality was observed for unfit patients at any timepoint after 100 days from first CPX-351 induction. Competitive risk analyses showed no differences in terms of early death by relapse between the two groups. With a median follow up of 24 months, unfit pts were characterized by a significantly shorter OS as compared to fit ones (median OS of 8 months [CI 95%: 4.1-11.8] and of 18 months [CI 95%: 14.7-21.1] for unfit and fit pts, respectively; p&amp;lt;0.0001) [Figure 1]. When stratified according to genetic/cytogenetic, median OS of fit pts was commensurate with ELN2017 risk (median OS not reached vs 20 months vs 13 months for favorable vs intermediate vs adverse risk, respectively; p &amp;lt; 0.01), whereas no differences in median OS were observed between favorable, intermediate, and adverse categories in unfit pts (median OS of 20 months vs 11 months vs 7 months, respectively; p=NS). Conclusions: In our real-life analysis, we demonstrated that fitness assessment according to SIE/SIES/GITMO criteria identifies populations with discrete outcome among t-AML and AML-MRC pts receiving CPX-351. In unfit patients, outcome prediction seems independent from ELN 2017 risk stratification. Fit and unfit groups achieved similar CR rates but different long-term OS. Such discrepancy can be justified by the higher early mortality observed among unfit pts that translated into shorter long-term survival. In a future perspective, modulating CPX-351 schedule in this group may be a reasonable option to spare toxicity without giving up the opportunity to deliver curative-intended therapies.

A High Percentage of DNAM-1+ and Low Percentage of Tactile+ NK Cells at Diagnosis Correlate with Complete Response and Survival in AML: A Sub-Analysis of the Ven-a-Qui Pethema Trial

Background: Natural killer (NK) immune status in Acute Myeloid Leukemia (AML) could influence therapeutic results and natural history of the disease. Objectives: In the phase I/II VEN-A-QUI (Clinical trials NCT04687761) clinical trial for unfit newly diagnosed AML patients (venetoclax+Quizartinib+azacytidine or low-dose cytarabine), it was planned a prospective study of NK populations and their influence in the main clinical outcomes. NK cells were analyzed at the diagnosis in a central laboratory. Material and methods: We analyzed NK cell subpopulations based in the expression of DNAM-1, TIGIT, TACTILE, CD8, PD-1, TIM-3, LAG-3, NKp44, NKp46, NKp30, CD16, CD85j,KIR2D, NKG2C, NKG2A, CD57, CD6, CD244, NKp80, Perforin, Granulolysin and Granzyme B. We compare composite Complete Remission (CRc) results of the Venetoclax/Quizatinib with Aza or Cytarabine vs. not achieving CRc using t Student. MaxStat statistics was used to test the significant limit of those populations with a significant difference (R-statistics version 4.2.2). Survival analysis comparing significant differences between patients in CRc was performed using LogRank test and Kaplan Maier. Cox survival analysis was performed to evaluate if the presence of this populations could be an independent factor against the European Leukemia Net classification of 2017 and p53. Data of molecular characteristics were obtained with an NGS panel of 40 genes. RESULTS: The trial included 76 ineligible patients for intensive chemotherapy (37 and 39 were in Aza and LDAC arms respectively). cCR was obtained in 39 patients (51.3%). ELN2017 risk was favorable in 8, intermediate in 15, and Adverse in 53. In 70 patients NK cell populations were analyzed (4 patients with very low percentage of NK cells, 2 with no sample at diagnosis were excluded from the study). There were significant differences between patients who achieve CRc and those who did not, according to DNAM-1 (74.4% vs 61.9, p=0.0018) and TACTILE (62% vs. 72%, p=0.02) expression on NK cells. The rest of antigens analyzed on NK cells were not significant. We found a cutoff of 62% of DNAM-1+ and less than 81% of TACTILE to differentiate populations in terms of survival using long-rank test. The number of DNAM-1 positive was 47 (60%) and TACTILE- was 55 (78%). The median OS of DNAM-1+ was better than DNAM-1− (18.4 vs 4.7 months, p=0.0001), and between TACTILE− vs TACTILE+ (17,36 vs. 4.6 months, p=0.005). Using an Cox model comparing karyotype, p53 and DNAM-1+ and TACTILE-, only DNAM-1+ was associated with better outcome (HR:0.33 (0.17-0.66) and TACTILE+ with worse (HR: 2.44 (1.20-4.99) in multivariate analysis. Conclusions: DNAM-1(CD226) positive and TACTILE (CD96) negative NK cell populations are associated to CR and better OS. These findings need to be confirmed in larger studies. Interestingly, DNAM-1 is an activating receptor and TACTILE is an inhibitory receptor for NK cells that share the same CD155 ligand but display opposite function.

RUNX1 Mutation Does Not Significantly Impact the Outcome of Newly Diagnosedadult AML: A Retrospective Study of Chinese AML Patients

Background RUNX1 is one of the recurrent mutated genes in newly diagnosed acute myeloid leukemia (AML) with a frequency of 6%~15%. Although historically recognized as a provisional distinct entity, the AML subtype with RUNX1 mutations (AML- RUNX1mut) was eliminated from the 2022 WHO classification system. With the update of AML diagnosis and treatment protocol, different outcomes of AML- RUNX1muthave been reported. However, an in-depth study about the prognostic value of RUNX1 mutations, epecifically the classification change related to AML- RUNX1mut in a large well-annotated cohort is lacking. Methods The clinical data of 1065 AML (excluding acute promyelocytic leukemia and RUNX1 germline mutations) patients according to WHO 2016 and treated from January 2017 to December 2021 at Jiangsu Institute of Hematology were retrospectively collected and analyzed after informed consent. All AML diagnosis samples were analyzed by targeted Next Generation Sequencing (NGS) panel covering 172 frequently mutated genes in hematological malignancies. Demographic and clinical data, disease characteristics at diagnosis, first-line treatment and clinical outcome data were available for all patients. The survival time of allogeneic hematopoietic stem cell transplantation patients was censored at the time of stem cell transfusion. Cytogenetic and molecular characteristics were used to classify patients into ELN2017 and ELN2022 risk groups (excluding the effect of RUNX1 mutation). Results RUNX1 mutations were detected in 112 (10.5%) patients, namely, 66 (58.9%) male and 46 (41.1%) female. A total of 132 RUNX1 alterations were detected with a medianvariant allelic frequency of 40% (3%~93%). RUNX1 mutations were associated with older age (48.5 vs. 46.0 years old, P=0.087) and antecedent myeloid disorders (6.3% vs. 1.0%, P&amp;lt;0.001). One or more comutations were detected in 106 (94.7%) AML- RUNX1mut patients. The most frequent co-gene abnormalities were FLT3-ITD and DNMT3A mutations which represented the 23.2% and 18.7%. Mutations of CEBPA bZIP, NPM1 and translocations of t(8;21), t(16;16)/inv(16) were uncommon in AML- RUNX1mut with a frequency of 6.3%, 1.8%, 2.7%, 0%, respectively (Table 1). Compared with AML with wild-type RUNX1 (AML- RUNX1wt), AML- RUNX1mut patients had a lower complete remission rate (19.6% vs. 29.7%, P=0.034), lower overall response rate (ORR) (73.5% vs. 84.3%, P=0.006) and higher no response rate (26.5% vs. 15.5%, P=0.021) in the first induction chemotherapy. When comparing groups based on the ELN2017 risk stratification criteria, no significant difference in ORR was observed between RUNX1mut and RUNX1wt patients in the favorable (91.2% vs. 94.0%, P=0.572), intermediate (75.0% vs. 78.4%, P=0.570) and adverse (63.3% vs. 71.4%, P=0.370 ) subgroups (Table 2). The median duration of follow-up of the entire cohort was 8.7 months ( RUNX1wt: 8.4 months; RUNX1mut: 10.0 months). Comparing the two groups, patients with RUNX1 mutations had a lower 5-year overall survival (OS) rate (35.4% vs. 42.3%; HR=1.563; 95% CI: 1.091~2.237, P=0.026), but no significant difference was observed in the 5-year event-free survival (EFS) rate (40.8% vs. 35.4%; HR=1.084; 95% CI: 0.750~1.570, P=0.098) (Table 2). However, when patients were stratified according to the ELN2017 guidelines (excluding the effect of RUNX1 mutation), outcomes did not differ between patients withor without RUNX1 mutation in the favorable (OS: P=0.629, EFS: P=0.137), intermediate (OS: P=0.629, EFS: P=0.114) and adverse (OS: P=0.544; EFS: P=0.714) subgroups. Similar results were obtained according to the ELN2022 guidelines. In multivariate analysis, RUNX1 was not an independent prognostic factor for OS (HR=1.353, 95% CI: 0.922~1.985, P=0.122) and EFS (HR=1.422, 95% CI: 0.975~2.075, P=0.068), while significantly worse OS and EFS were observed in patients with mutated FLT3-ITD, TP53, and DNMT3A ( P-values were all less than 0.05). Conclusion RUNX1 mutations were rarely isolated genetic abnormities that conferred inferior outcomes. However, on the basis of ELN prognosis risk stratification, RUNX1mutation had no impact on the clinical outcomes of AML patients in stratified subgroups. RUNX1 was not an independent prognostic factor for survival. Overall, our findings agree with the updated WHO classification system for AML that AML- RUNX1mut should not be recognized as a distinct AML entity.

Homoharringtonine Overcomes the Negative Impact of Genetic Patterns on Venetoclax Plus Azacitidine Regimen in Relapsed/Refractory Acute Myeloid Leukemia: A Multi-Center, Cohort Study

Objective: Whether other agents added to venetoclax (VEN) plus hypomethylating agents (HMA) regimen could overcome the negative impact of genetic patterns on response in patients with relapsed/refractory acute myeloid leukemia (RR-AML) remains unclear. Aim of this study was to evaluate whether homoharringtonine (HHT) added to VEN plus azacitidine (AZA) regimen could improve the response and overcome the negative impact of genetic patterns in patients with RR-AML . Methods: A multi-center, cohort study of the response and the genetic patterns of response of VEN plus AZA and HHT (VAH) versus VEN plus AZA (VA) regimens as salvage treatment in the patients with RR-AML was performed. Patients were enrolled from four studies from October 2018 to December 2022 at nine medical centers in china. Results: A total of 321 patients were analyzed, including 150 females and 171 males, with a median age at 46 (IQR, 35-61) years. There were 172 patients in the VAH and 149 in the VA group. VAH significantly improved CRc rate (66.3% vs. 44.3%, P&amp;lt;0.001) and prolonged OS (median OS, not reach vs. 14.3 months, P=0.004), to compared with VA. Multivariate analysis showed that VAH was the independently protective factor for CRc and survival. In addition, VAH significantly overcame the negative impact of FLT3-ITD/TKD, N/KRAS, TET2, DNMT3A mutations, and t(8;21)/AML1-ETO, as well as non-adverse ELN risk, also apparently in adverse ELN risk or complex karyotype, on the response of VA regimen. Conclusion: The impact of genetic patterns on the response presented diversely in different VEN-based regimens. HHT added to VA regimen might improve the response and overcome the negative impact of part genetic patterns in RR-AML. Key words: homoharringtonine, venetoclax, relapsed/refractory, acute myeloid leukemia, genetic pattern

Analysis of Treatment Patterns and Outcomes in Patients Ages 60-74 in the Post-Venetoclax Era

Introduction Clear standards of care exist for patients with AML under the age of 60 who are eligible for intensive chemotherapy (IC), as well as for patients over the age of 75 or who are unfit for IC. Fit patients between the ages of 60-74 have historically been understudied, but have lower rates of remission and increased rates of toxicity with intensive regimens compared to younger individuals with AML. We sought to evaluate treatment patterns and outcomes in this patient group. Methods We performed a single-center, retrospective analysis of consecutive patients ages 60 through 74 years at the time of their AML diagnosis who received frontline therapy between April 2018 and September 2022. Low intensity therapy (LIT) regimens included combinations of a hypomethylating agent, low dose cytarabine, venetoclax, cladribine, and/or targeted agents. IC regimens included an anthracycline and higher-dose cytarabine-based regimens (≥1g/m 2) +/- targeted agents. Clinical and genomic data including patient demographics, laboratory results including bone marrow pathology and mutational data, treatment responses, and allogeneic hematopoietic stem cell transplantation (HCT) data including conditioning regimen and donor type (when applicable) were abstracted from the medical record. Minimal residual disease (MRD) status was assessed by multi-parameter flow cytometry with a sensitivity of 0.02%. The statistical analysis was performed using R 1. Results 143 patients were included in the analysis; 47 (33%) received front line IC, and 96 (67%) received LIT. Baseline characteristics are shown in Table 1. Patients receiving IC were younger, more likely to be female, and more likely to have a favorable ELN risk stratification 2, but otherwise balanced. The percentage of patients receiving IC remained the same in each calendar year. Patients in the IC and LIT groups had similar rates of complete remission (CR; 70% vs 70%, respectively, p = 0.96). Among those achieving CR, 22 (67%) patients in the IC group achieved MRD-negativity vs. 35 (52%) in the LIT group (p = 0.17). The median duration of remission was 9 months in the IC group and 12 months in the LIT group (p = 0.17). The median overall survival (OS) was 17 months for IC and 15 months for LIT (p = 0.16). For patients harboring FLT3-ITD, IDH1, IDH2, or TP53 mutations, there was no difference in OS based on receipt of either IC or LIT, nor was there any difference in OS according to ELN 2022 risk category. A significantly higher proportion of patients who received IC underwent HCT (68% vs 42%, p = 0.003). In both groups, OS was significantly longer for patients who received HCT. Treatment-related mortality (TRM) was comparable in each group, with 5 (11%) and 8 (8%) deaths in IC vs. LIT, respectively. The median number of days hospitalized within the first 60 days after induction therapy was notably different at 32 days for IC and 5.5 days for LIT (p &amp;lt; 0.00001), with 34 (35%) LIT patients who had 0 days of hospitalization post-induction compared to IC patients who universally were hospitalized as part of their induction treatment plan. Conclusion In our cohort, patients with AML between the ages of 60-74 had comparable rates of CR, MRD negativity, duration of response, and overall survival whether treated with IC or LIT, with no difference when stratified by mutational status or ELN risk. Intensively-treated patients were younger and more likely to receive HCT but both groups had an OS benefit from HCT. Our data suggest that in the era of novel agents such as venetoclax, less intensive induction strategies may be appropriate for IC-eligible patients between the ages of 60-74. References 1R Core Team (2021). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. https://www.R-project.org/. 2Döhner H, Wei AH, Appelbaum FR, Craddock C, DiNardo CD, Dombret H, Ebert BL, Fenaux P, Godley LA, Hasserjian RP, Larson RA, Levine RL, Miyazaki Y, Niederwieser D, Ossenkoppele G, Röllig C, Sierra J, Stein EM, Tallman MS, Tien HF, Wang J, Wierzbowska A, Löwenberg B. Diagnosis and management of AML in adults: 2022 recommendations from an international expert panel on behalf of the ELN. Blood. 2022 Sep 22;140(12):1345-1377. doi: 10.1182/blood.2022016867. PMID: 35797463.

Molecular Characterisation and Outcomes of 363 Adolescent and Young Adults with AML in Saudi Arabia Risk Stratified By PCR and NGS-Based Testing

Introduction Acute Myeloid Leukaemia (AML) is characterised by cytogenetic (CGN) abnormalities and or mutations in one or more of a number of genes that allow risk stratification and guide treatment. The mutational landscape of patients from Saudi Arabia, which has a young population, has not been well characterised. One study indicates a higher rate of core binding factor and monosomies. Mutational analysis by Next generation sequencing (NGS) has not had widespread utilisation hampering the risk stratification of AML in the country. The more recent introduction of NGS panels has allowed more risk stratification. Here we analysed patients and characterised the CGN and molecular abnormalities. Methods Data were collected from 363 patients, and their cytogenetic and molecular results were reviewed. Patients were divided into 2 cohorts: Cohort A only had PCR-based testing diagnosed or treated at King Faisal Specialist Hospital and research centre - Riyadh. PCR testing included mutation analysis for FLT3, NPM1, CEBPA, c-KIT, IDH1, IDH2, WT1, DNMT3A, and JAK2; quantitative PCR for RUNX1-ETO in a subset of patients. Cohort B had PCR-based mutation testing in addition to the Next-Generation Sequencing (NGS) myeloid panel, which was Illumina-based or Ion Torrent. The panel comprises 23 hotspot genes, 17 entire genes, 29 fusion drivers, and five expression genes associated with haematological malignancies. We risk-stratified patients according to the most recent testing method available. Cohort A and Cohort B were risk-stratified, according to ELN risk classification 2017. Survival analysis for these patients was conducted. Results The median age for all patients was 39 years (13-89). PCR testing included mutation analysis for FLT3 (93.4%), NPM1 (90.4%), CEBPA (69.7%), c -KIT (54.3%), IDH1 (57%), IDH2 (57.9%), WT1 (61.2%), DNMT3A (54.5.5%), JAK2 (4.7%) and quantitative PCR for RUNX1- ETO fusion (13.2%). Cohort A comprised 262 (72.7%) patients who underwent PCR-based mutation testing only. Cohort B consisted of 101 (27.8%) patients who underwent PCR-based mutation testing in addition to NGS myeloid panel analysis. In the entire cohort of 363 patients, we found FLT3-ITD mutations in 85 patients (23.4%) and NPM1 mutations in 68 (18.7%). 36 patients (9.9%) harboured both FLT3-ITD and NPM1 mutations together. In Cohort A, FLT3-ITD detected 26.7% of patients, and 20.2% had NPM1 mutation, while 40% had no detectable mutations by conventional PCR. On the other hand, FLT3-ITD was detected in 14.9% of patients by both NGS and conventional PCR and in 14.9% of patients with NPM1. When comparing Cohort A and Cohort B, Cohort B had more mutations in genes that play an important role in myeloid malignancies, which might have better risk stratification and precision, including TP53 in 13.9% of patients and RUNX1 in 18.8% of patients and ASXL1 in 9.9% of patients. Moreover, NGS pick up more mutations in CEBPA, c-KIT, WT1, IDH1 and JAK2 genes compared to conventional PCR. Within cohort A, 9.2% of patients had normal cytogenetic testing results with no detectable mutations, whereas in cohort B, only 1% of patients had normal karyotype and molecular testing. Furthermore, six mutations were detected only by NGS but not PCR in FLT3-ITD, CEBPA, c-KIT, IDH2, WT1 and DNMT3A in 5.9% of patients. Cohorts A and B were also categorised into ELN risk groups using PCR, sequencing, and cytogenetics testing. It was found that patients at adverse risk had shorter overall survival compared to those at intermediate or favourable risk in both cohorts, with p-values of 0.030 and 0.0007, respectively (Figure 1). The use of NGS was found to be more effective than conventional testing in identifying patients with adverse risk, with a hazard ratio for death of 0.22 (95% CI, 0.08989-0.5732) compared to a hazard ratio of 0.66 (95% CI, 0.4352 -1.031) for conventional PCR testing. Conclusion In this study, we present the mutational profile of AML in young Saudi patients and identify certain frequent mutations in this population. The study presents the largest molecular profiling to our knowledge of this population. The study emphasises the need for integration of NGS to enhance risk stratification and precision, enable better characterisation of high-risk patients, and improve the potential for targeted treatments.