FLT3 mutation

Finally, recent data also suggest FLT3 inhibitors could transform outcomes in patients unsuitable for intensive therapy. If confirmed, this has important implications for fit patients and could revolutionize the treatment paradigm.

Our results suggest different immunosuppressive effects of these three FLT3i and may, therefore, provide an additional rationale for optimal maintenance therapy after alloHSCT of FLT3-positive AML patients to prevent infectious complications and GvHD mediated by DCs.

Our findings suggest the addition of HHT to VA might enhance response and mitigate the negative impact of certain genetic patterns in RR-AML while being well tolerated.

We next use a generalizable, reversible approach to demonstrate that mutation reversion results in rapid leukemic regression with distinct differentiation patterns depending upon co-occurring mutations. These studies provide a path to experimentally model sequential mutagenesis, investigate mechanisms of transformation and probe oncogenic dependency in disease evolution.

P1, N=0, Withdrawn, Beijing Boren Hospital | Trial completion date: Dec 2025 --> Dec 2023 | Recruiting --> Withdrawn | Trial primary completion date: Dec 2024 --> Dec 2023

P4, N=180, Not yet recruiting, Qilu Hospital of Shandong University; Qilu Hospital of Shandong University

P3, N=158, Active, not recruiting, Children's Oncology Group | Trial completion date: Sep 2024 --> Sep 2025

For patients with IDH1 mutated AML co-mutated with NPM1 and/or FLT3-ITD, only detection of persistent mutated NPM1 and/or FLT3-ITD was associated with significantly higher rates of relapse (p = 0.01). These data, from the largest study to date, do not support the detection of IDH1 mutation in CR1 blood prior to alloHCT as evidence of AML MRD for increased post-transplant relapse risk.

In this interim analysis, gilteritinib 120 mg/day in combination with chemotherapy was well tolerated, with similar CRc rates to previous studies.

NPM1 MRD positive patients receiving nonmyeloablative conditioning or reduced-intensity conditioning (RIC) without melphalan (mel) had increased risk of relapse or death compared to patients receiving myeloablative conditioning or RIC with mel, regardless of FLT3-ITD co-mutational status (3yrs: relapse 87% vs 55%, P=0.006; OS 15% vs 42%, P=0.013). In patients with NPM1 mutated AML from the Pre-MEASURE study, we show that detection of residual NPM1 variants in pre-transplant blood during CR1 using a highly sensitive DNA-based assay is associated in a dose-dependent manner with a significantly increased risk of relapse and death after allo-HCT, which can be mitigated in part by conditioning regimen. In patients co-mutated for both FLT3-ITD and NPM1 at diagnosis, NPM1 should be prioritized as a target for NGS-MRD if only one test is available.

We then profiled a wet-lab cohort of 37 FLT3-mut AML patients treated either with Midostaurin plus chemotherapy (M) or Gilteritinib (G) at Bologna Hematology Institute by using the PanCancer IO 360 Panel (NanoString Technologies, San Diego, CA). This study provides evidence that FLT3 mutational status is associated with a unique T-cell activation profile and AML maturation state, and that T/NK cell-associated genes correlate with response to FLT3i. Our RNA metric of FLT3 mutational status could be utilized to refine patient stratification in future clinical trials. S.R.

The newly established morphologic classification system in this study can objectively characterize different types of APL blast cells, which helps to better assess the intra- and inter-individual heterogeneity of APL blast cells, and further use in accurately analyzing the correlation of morphological phenotypes with biological properties of APL.

Our findings contribute to a comprehensive characterization of NPM1-mutated AML, enhancing diagnostic accuracy and aiding in the detailed classification of the disease. This information may potentially guide targeted therapies or differentiation-based treatment strategies.

Considering both treatment groups, if only 24% of FLT3-ITD microclones detected at diagnosis were retained at relapse, 43% of them became macroclones. Together, these results identify parameters influencing the fitness of FLT3-ITD clones and highlight the importance of using sensitive techniques for FLT3--ITD screening in clinical practice.

No abstract available

Inflammasome activation was also shown to strongly increase the likelihood of a poor ex vivo response to the FLT3 inhibitors quizartinib and sorafenib. These findings reveal a distinct molecular pattern within FLT3-ITD AML samples that underscores the necessity for further exploration into how approaching these supportive parallel yet altered pathways could improve therapeutic strategies.

The present study aimed to gain insights into the molecular interactions and affinity forces of four TKI drugs (sorafenib, midostaurin, gilteritinib and quizartinib) with the wild‑type (WT)‑FLT3 and ITD‑mutated (ITD‑FLT3) structural models of FLT3, in its inactive aspartic acid‑phenylalanine‑glycine motif (DFG‑out) and active aspartic acid‑phenylalanine‑glycine motif (DFG‑in) conformations. Thus, the current study presented novel information about molecular interactions between the FLT3 receptors (WT or ITD‑mutated) and some of their inhibitors. It also paves the way for the search for novel inhibitory molecules with potential use against AML.

The genetic profile of these mutCFN CMML patients closely resembled that of AML, with higher-risk clinical characteristics. Our findings lead us to suggest including the assessment of these mutations in CMML prognostic models and treating these patients with AML-type therapies, including intensive chemotherapy and allogeneic stem cell transplantation, whenever feasible, and consider certain targeted therapies approved for use in AML.

In the decitabine plus midostaurin arm 24% reached CR/CRi, the median OS was 4.8 months and 1-yrs OS was 31% which compared with 34% CR/CRi, median OS of 7.4 months and 1-yrs OS of 37% for the decitabine alone group (NS). Thus, while the addition of midostaurin appears safe, it does not enhance therapeutic efficacy of decitabine in unfit AML patients.

P1/2, N=45, Recruiting, Australasian Leukaemia and Lymphoma Group | Not yet recruiting --> Recruiting

In Japan, alongside monotherapy with gilteritinib or quizartinib for relapsed/refractory patients, combination of quizartinib with intensive chemotherapy was approved in 2023 for untreated FLT3-ITD mutation-positive AML. Thus, FLT3 mutations are utilized not only as a prognostic factor in AML but also as a target for treatment and for response assessment. Furthermore, the development of new treatment strategies involving FLT3 inhibitors is highly anticipated to improve clinical outcomes for patients with FLT3 mutation-positive AML.

However, resistance to targeted therapies is also a challenge. This Progress in Hematology features current trends and challenges in favorable-risk AML and FLT3 mutations that are frequently identified in these patients.

In a xenograft model, the combination of gilteritinib and 25HC showed significantly better efficacy than either monotherapy in suppressing lung cancer growth, without obvious general toxicity. Thus, our findings identify an increase in cholesterol induced by gilteritinib as a mechanism for LCC survival, and highlight the potential of combining gilteritinib with cholesterol-lowering drugs to treat lung cancer.

Adding venetoclax might not improve CR/CRi of IA. A well-designed prospective randomized controlled study is now warranted.

For Pt #1, disease resistance was associated with clonal expansion of minor clones, and 2nd line TKI therapy with gilteritinib provided a proliferative advantage to the clones carrying NRAS and KIT mutations, thereby responsible for relapse. In Pt #2, clonal architecture was less complex, and 1st line TKI therapy with midostaurin was able to eradicate the leukemic clones. Our results corroborate previous findings about clonal selection driven by TKIs, highlighting the importance of a deeper characterization of individual clonal architectures for choosing the best treatment plan for personalized approaches aimed at optimizing outcomes.

Our investigation confirmed that the morphological identification of CLB at diagnosis represents a reliable and easily reproducible tool for the early prediction of NPM1 mutations, enabling a streamlined genetic work-up for its confirmation. This may facilitate considering the early administration of individualized therapies by clinicians for specific patients.

Pathway enrichment analyses using GO and KEGG, along with protein-protein interaction network and single sample gene set enrichment analyses, revealed key pathways and immune cell associations linked to ARHGEF5. These findings suggest that ARHGEF5 overexpression could serve as a biomarker for unfavorable outcomes in AML, providing insights into the underlying mechanisms of AML onset and progression.

No abstract available

It has shown promise in clinical studies since 2013 due to its excellent oral absorption and potent activity on FLT3. This review explores Quizartinib's mechanism of action, efficacy in monotherapy or combination with chemotherapy, drug interactions, adverse events, resistance mechanisms and future research directions.

The expression levels of HSP90 and HSP110 correlate with reduced AML patient survival (p < 0.1) and HSP90, HSP110, and BIM are linked to the expression of FLT3 in primary AML cells (p < 0.01). HSP90 suppresses degrader-induced FLT3-ITD elimination and thereby establishes a mechanistically defined feed-back circuit.

In validation, MPhos outperformed the currently-used FLT3-based stratification method. Our findings have the potential to transform clinical decision-making, and highlight the important role that phosphoproteomics is destined to play in precision oncology.

P3, N=968, Active, not recruiting, Stichting Hemato-Oncologie voor Volwassenen Nederland | Recruiting --> Active, not recruiting | Trial completion date: May 2034 --> Sep 2034 | Trial primary completion date: Oct 2024 --> Apr 2027

P3, N=371, Active, not recruiting, Astellas Pharma Global Development, Inc. | Trial completion date: Aug 2024 --> Dec 2024

We then screened a cohort of FLT3-mut AML patients treated either with Midostaurin plus chemotherapy (M) or Gilteritinib (G) at Bologna Hematology Institute by using the PanCancer IO 360 Panel (NanoS-tring GEA). This study highlights how FLT3 mutational status is associated with T-Cell activation and AML maturation state. Differences in immune transcriptomic profile impact on FLT3i response.

In summary, our study demonstrated that the forms and impacts of FLT3 mutations in ALL differed significantly from those in AML. The gene expression profiles of FLT3-related pathways may provide a rationale for using FLT3 inhibitors in AML rather than ALL when FLT3 mutations are present.

The advent of FLT3 tyrosine kinase inhibitors (TKIs), such as midostaurin and gilteritinib, has shown promise in achieving complete remission. Specifically, we provide evidence for integrating gilteritinib with mammalian targets of rapamycin (mTOR) inhibitors and interleukin-15 (IL-15) complexes. The combination of gilteritinib, mTOR inhibitors, and IL-15 complexes presents a compelling strategy to enhance the eradication of AML blasts and enhance NK cell killing, offering a potential for improved patient outcomes.

In this study, we first observed that the combined use of FLT3 inhibitor gilteritinib and HDAC inhibitor vorinostat increased the survival rate of leukemia xenograft mouse model. Furthermore, compound 25h demonstrated superior anti-tumor efficacy in the MOLM-13 xenograft model compared to combination therapy, along with reduced in vivo toxicity. To conclude, we have identified a novel FLT3/HDAC dual inhibitor that could serve as a potential candidate for the treatment of AML.

Gilteritinib is the current standard of care for relapsed or refractory FLT3-mutated AML in many countries, however outcomes for patients relapsing after contemporary first-line therapies (intensive chemotherapy with midostaurin, or non-intensive chemotherapy with venetoclax) are uncertain. Twenty patients received gilteritinib as first salvage having progressed following first-line therapy with venetoclax, with CR/CRi achieved in 25% and median survival 4.5 months. Real-world results with gilteritinib mirror those seen in the clinical trials but outcomes remain suboptimal, with more effective strategies needed.

CS1 showed good sensitivity to cytarabine, while CS2 was sensitive to RXR agonists...With advancements in sequencing technology and machine learning algorithms, AML is poised to transition towards multi-omics precision medicine in the future. We aspire for our study to offer new perspectives on multi-drug combination clinical trials and multi-targeted precision medicine for AML.

In in vivo studies, SILA-123 significantly suppressed the tumor growth in MV4-11 (50 mg/kg/d, TGI = 87.3%) and BaF3-FLT3-ITD-G697R (50 mg/kg/d, TGI = 60.0%) cell-inoculated allograft models. Our data suggested that SILA-123 might be a promising drug candidate for FLT3-ITD-positive AML.

Thus, early CH-associated mutations that precede malignant transformation subsequently shape the evolutionary trajectories of AML through diagnosis, therapy, and relapse. DNMT3A , TET2 and ASXL1 mutations persist through AML-directed therapy Distinct CH-related mutations shape the evolutionary trajectories of AML from diagnosis through relapse.

The availability of FLT3 inhibitors has improved outcomes in AML harboring such mutations, currently also reflected in disease stratification and recommendations. Newer inhibitors are under investigations, and combinations with chemotherapy or other targeted treatments are being explored to further improve disease outcomes.