Vanflyta (quizartinib)

Gilter/quizar monotherapy are effective and tolerable options for patients with R/R FLT3mut AML in a real-world setting. Response and toxicity rates are similar to those reported in the phase 3 trials, despite the more heterogeneous nature of the study population.

All-trans retinoic acid (ATRA) is well known for its effectiveness in acute promyelocytic leukemia (APL) treatment and has already been shown to have synergistic effects combined with another TKI, sorafenib. Finally, in a xenotransplantation model ATRA plus AC220 was more efficient to reduce the leukemic burden than monotherapy with ATRA or AC220. Taken together, our results are a proof of the concept that ATRA and AC220 have synergistic anti-leukemic effects.

Since 2017, a turning point in AML research, 12 agents have received regulatory approval for AML in the United States: venetoclax (BCL2 inhibitor); gemtuzumab ozogamicin (CD33 antibody-drug conjugate); midostaurin, gilteritinib, and quizartinib (fms-like tyrosine kinase 3 inhibitors); ivosidenib, olutasidenib, and enasidenib (isocitrate dehydrogenase 1 and 2 inhibitors); oral azacitidine (a partially absorbable formulation); CPX351 (liposomal encapsulation of cytarabine:daunorubicin at a molar ratio of 5:1); glasdegib (hedgehog inhibitor); and recently revumenib (menin inhibitor; approved November 2024). Oral decitabine-cedazuridine, which is approved as a bioequivalent alternative to parenteral hypomethylating agents in myelodysplastic syndrome, can be used for the same purpose in AML. Menin inhibitors, CD123 antibody-drug conjugates, and other antibodies targeting CD123, CD33, and other surface markers are showing promising results. Herein, the authors review the frontline and later line therapies in AML and discuss important research directions.

P3, N=700, Recruiting, Daiichi Sankyo | Not yet recruiting --> Recruiting

Finally, we highlight some of the ongoing studies that test quizartinib in patients with FLT3-ITD-positive AML, patients with FLT3-ITD-negative AML, in both the first-line and R/R settings, in patients fit or unfit for intensive chemotherapy, including studies for quizartinib-based combination with other compounds such as decitabine and venetoclax. Future research should aim to further optimize the clinical value of quizartinib and explore its use in additional clinical settings, which could be achieved by testing quizartinib with other drugs, better characterization of the mechanisms of resistance, identification of the role of quizartinib as a maintenance therapy after allo-HCT, and investigating quizartinib in patients with FLT3-ITD-negative AML.

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.

This innovative TRG scoring model demonstrates considerable predictive value for AML patient prognosis, offering valuable insights for optimizing treatment strategies and personalized medicine approaches. The identified TRGs and associated scoring models could aid in risk stratification and guide tailored therapeutic interventions in AML patients.

P1/2, N=65, Active, not recruiting, Daiichi Sankyo | Recruiting --> Active, not recruiting

P1/2, N=84, Ongoing, Fundación Pethema

Therefore, quizartinib and gilteritinib are second-generation FLT3 inhibitors that are frequently applied for treating patients with AML. In conclusion, these findings suggest that second-generation FLT3 inhibitors can improve the overall survival of patients with AML. However, QTc prolongation is a potential adverse effect that should be monitored.

The patient achieved hematological CR on day 163 and remained in molecular CR 3 years after allo-HCT without adverse effects. Quizartinib combined with DLI may be a feasible treatment for early relapse of FLT3-ITD-positive AML after allo-HCT, even with concurrent DNMT3A and NPM1 mutations.

Notably, compound 49 demonstrated cytotoxic effects in Ba/F3 cells expressing FLT3-ITD or FLT3-ITD-F691L mutant, exceeding the potency of both sorafenib and quizartinib. The study suggests that substituted furo[2,3-d]pyrimidines could be useful additions to the growing field of FLT3-targeted therapy for AML. These compounds have the potential to serve as novel FLT3-ITD inhibitors and may offer insights for developing future therapeutic strategies in AML.

Polθ inhibitors enhanced the anti-leukemic effects of mainstream drugs such as FLT3 kinase inhibitor quizartinib, cytarabine and etoposide in vitro and in mice with FLT3(ITD);DNMT3Amut leukemia. Altogether, Polθ is an attractive target in DNMT3Amut hematological malignancies.

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.

"Invivoscribe is excited to announce that their CE-2797 IVD certified LeukoStrat CDx FLT3 Mutation Assay has been approved by BSI (Netherlands) and the EMA to aid in the selection of individuals in the European Union and European Economic Area with newly diagnosed FLT3-ITD positive acute myeloid leukemia (AML) who may be eligible to receive treatment with Daiichi Sankyo’s VANFLYTA (quizartinib)...In regions where XOSPATA (gilteritinib fumarate) is available, the LeukoStrat CDx FLT3 Mutation Assay is used as an aid in the assessment of patients with AML for whom XOSPATA (gilteritinib fumarate) treatment is being considered...In regions where VANFLYTA (quizartinib hydrochloride) is available, the LeukoStrat CDx FLT3 Mutation Assay is used as an aid in the assessment of patients with FLT3-ITD+ AML for whom VANFLYTA (quizartinib hydrochloride) treatment is being considered."

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.

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.

Since 2017, twelve agents have been approved for the treatment of AML subsets: the BCL2 inhibitor venetoclax; the CD33 antibody drug conjugate gemtuzumab ozogamicin; three FLT3 inhibitors (midostaurin, gilteritinib, quizartinib); three IDH inhibitors (ivosidenib and olutasidenib targeting IDH1 mutations; enasidenib targeting IDH2 mutations); two oral hypomethylating agents (oral poorly absorbable azacitidine; fully absorbable decitabine-cedazuridine [latter approved as an alternative to parenteral hypomethylating agents in myelodysplastic syndrome and chronic myelomonocytic leukemia but commonly used in AML]); and CPX-351 (encapsulated liposomal 5:1 molar ratio of cytarabine and daunorubicin), and glasdegib (hedgehog inhibitor)...To achieve optimal results in such a rare and heterogeneous entity as AML requires expertise, familiarity with this rare cancer, and the access to, and delivery of disparate therapies under rigorous supportive care conditions. In this review, we update the standard-of-care and investigational therapies and outline promising current and future research directions.

P1/2, N=8, Terminated, M.D. Anderson Cancer Center | Completed --> Terminated; This study was terminated early due to other competing trials, therefore did not go on to the Phase II portion of the study.

Hypomethylating agents like azacitidine and decitabine have shown promise in improving relapse-free and overall survival, particularly in older patients with AML ineligible for transplantation. Combination regimens involving azacitidine and venetoclax have demonstrated encouraging outcomes post-hematopoietic stem cell transplantation. Targeted therapies, particularly FLT3 inhibitors like midostaurin and quizartinib, have shown significant benefits in improving survival outcomes, especially in FLT3-mutated AML cases. Gilteritinib and sorafenib also exhibit the potential to reduce relapse rates post-transplant. Isocitrate dehydrogenase inhibitors, including ivosidenib and enasidenib, present novel options for postchemotherapy and posttransplantation maintenance...The approval of oral azacitidine represents a significant advancement, emphasizing the need for further investigation into personalized maintenance approaches. In conclusion, the evolving landscape of maintenance therapy and integrating targeted therapies in AML offers promising avenues for improving patient outcomes.

P3, N=700, Not yet recruiting, Daiichi Sankyo

Dobutamine as a monotherapy can inhibit theproliferation of FLT3-ITD mutated AML cells, inducing apoptosis. Additionally, the combination of quizartinib enhances the targeted inhibitory effect on FLT3-ITD mutated AML. The mechanism may involve the inhibition of YAP1 protein expression in AML cells of this type, leading to an increase in ROS levels and exerting its anti-tumor effects.

Since then, the understanding of the molecular pathogenesis of AML has expanded, allowing the identification of additional potential targets for drug therapy, treatment incorporation of molecularly targeted therapies (midostaurin, gilteritinib, and quizartinib targeting FLT3 variants; ivosidenib and olutasidenib targeting IDH1 variants, and enasidenib targeting IDH2), and identification of rational combination regimens. The approval of hypomethylating agents combined with venetoclax has revolutionized the therapy of AML in older adults, extending survival over monotherapy. Additionally, patients are now referred for hematopoietic cell transplant on a more rational basis. In the era of genomic medicine, AML treatment is customized to the patient's comorbidities and AML genomic profile.

These findings establish the sphingolipid metabolic enzyme SPHK1 as a regulator of TKI sensitivity and suggest that combining SPHK1 inhibition with TKIs could be an effective approach for treating FLT3-mutated AML.

In Japan, the combination of quizartinib and intensive chemotherapy for untreated FLT3-ITD-positive AML was approved in 2023...Meanwhile, various resistance mechanisms to FLT3 inhibitors have been identified, including the emergence of resistance-associated mutations, and attenuated inhibitory effects of FLT3 inhibitors involving the bone marrow microenvironment surrounding AML cells. Thus, future efforts should aim to optimize combination therapy based on the characteristics of each FLT3 inhibitor, develop biomarkers that could inform treatment selection, and to better understand these resistance mechanisms and develop methods for overcoming them.

Next, we explored the latest FLT3-targeting PROTACs developed in the past few years such as quizartinib-based PROTACs, dovitinib-based PROTACs, gilteritinib-based PROTACs, and others. Then, we followed with a deep analysis of their advantages regarding potency improvement and overcoming AML drug resistance. Finally, we discussed the challenges facing these chimeric molecules with proposed future solutions to circumvent them.

Other FLT3 inhibitors, midostaurin, crenolanib, and quizartinib, also reduced FLT3 expression, consistent with the effect of gilteritinib. These findings hold great promise for optimizing gilteritinib treatment in AML patients. However, it is important to recognize that further research is warranted to gain a full understanding of these mechanisms and their clinical implications in the context of FLT3 reduction.

Three relevant randomized controlled trials (RCTs), involving 1.358 patients treated with midostaurin, quizartinib, and sorafenib, were included in our analysis. This NMA, the first to explore this issue, found no OS differences among the different FLT3 inhibitors. In the absence of direct comparison trials, our findings provide practical insights for clinical decision-making.

Overall, our study confirmed the therapeutic role of ningetinib in AML with FLT3-ITD mutations, providing a potential new option for clinically resistant patients.

AML patients treated with investigational drugs targeting mutant FLT3, including Quizartinib and Crenolanib, develop resistance to these drugs...We have identified 2 novel nicotinamide-based FLT3 inhibitors (HSN608 and HSN748) that target FLT3 mutations at subnanomolar concentrations and are potently effective against drug-resistant secondary mutations of FLT3. These compounds show antileukemic activity against FLT3ITD in drug-resistant AML, relapsed/refractory AML, and in AML bearing a combination of epigenetic mutations of TET2 along with FLT3ITD. We demonstrate that HSN748 outperformed the FDA-approved FLT3 inhibitor Gilteritinib in terms of inhibitory activity against FLT3ITD in vivo.

Utilizing various models of persistent leukemia, we demonstrated that leukemic cells resistant to Quizartinib are susceptible to L-Asparaginase. This combined therapeutic strategy shows promise in reducing the development of resistance to FLT3 inhibitors, offering a potential strategy to enhance treatment outcomes.

We searched and reviewed clinical trial reports on the monotherapy of 13 FLT3 inhibitors, including sorafenib, lestaurtinib, midostaurin, gilteritinib, quizartinib, sunitinib, crenolanib, tandutinib, cabozantinib, pexidartinib, pacritinib, famitinib, and TAK-659 in patients with hematological and solid malignancies before May 31, 2023...The ORRs of FLT3 inhibitors in hematologic malignancies and solid tumors were 40.8% and 18.8%, respectively, indicating FLT3 inhibitors were more effective for hematologic malignancies than for solid tumors. In addition, time to maximum plasma concentration (Tmax) in these FLT3 inhibitors ranged from 0.7-12.0 hours, but the elimination half-life (T1/2) range was highly variable, from 6.8 to 151.8 h. FLT3 inhibitors monotherapy has shown significant anti-tumor effect in clinic, and the effectiveness may be further improved through combination medication.

P1/2, N=58, Recruiting, M.D. Anderson Cancer Center | Trial completion date: Dec 2024 --> Dec 2025 | Trial primary completion date: Dec 2024 --> Dec 2025

In addition, the review discusses the emergence of drug resistance and the need for a nuanced approaches in treating patients who are ineligible for or resistant to intensive chemotherapy. Specifically, it explores the historical context of FLT3 inhibitors (FLT3Is) and their impact on treatment outcomes, emphasizing the pivotal role of midostaurin, as well as gilteritinib and quizartinib, and providing detailed insights into ongoing trials exploring the safety and efficacy of novel triplet combinations involving FLT3Is in different AML settings.

Hence, FLT3 is considered an attractive druggable target; selective small FLT3 inhibitors (FLT3Is), such as midostaurin and quizartinib, have been clinically approved. Therefore, understanding the role of different epigenetic alterations in FLT3-ITD AML pathogenesis and how they modulate FLT3I's activity is important to rationalize combinational treatment approaches including FLT3Is and modulators of methylation regulators or pathways. Data from ongoing pre-clinical and clinical studies will further precisely define the potential use of epigenetic therapy together with FLT3Is especially after characterized patients' mutational status in terms of FLT3 and DNA methlome regulators.

These targeted therapies offer promise for managing this subgroup of AML patients, but further research is needed to optimize their use. This study underscores the importance of personalized treatment based on genetic mutations in AML, paving the way for more effective and tailored approaches to combat the disease.

Drug sensitivity of MV411 cells to doxorubicin, quizartinib and midostaurin can be enhanced significantly after miR-155 knockout, which is related to the inhibition of multiple signaling pathways including mTOR and Wnt signaling pathways.

With an incremental gain of 0.84 quality-adjusted life years (QALYs) with quizartinib + 7 + 3 induction vs. 7 + 3 alone, the incremental cost-effectiveness ratio for the addition of quizartinib to standard 7 + 3 was $344,039/QALY. Only an 87% reduction in the average wholesale price of quizartinib or omitting quizartinib continuation therapy after completion of consolidation therapy and allogeneic hematopoietic cell transplant would make quizartinib a cost-effective option.

The present study finally identified seven glycolysis-related lncRNAs (CRNDE, AC022034.1, RHOQ-AS1, AL159169.2, AL133215.2, AC007098.1 and LINC02587) to construct a prognosis prediction model...The experimental results demonstrated that CRNDE could increase the proliferation of SHG-44 cells. In conclusion, a large sample of human grade II-III glioma in The Cancer Genome Atlas database was used to construct a risk model using glycolysis-related lncRNAs to predict the prognosis of patients with grade II-III glioma.

P1/2, N=73, Completed, M.D. Anderson Cancer Center | N=200 --> 73

P2, N=60, Recruiting, Princess Maxima Center for Pediatric Oncology