Vanflyta (quizartinib)

Currently, most leukemias are effectively treated with immunotherapies (highly effective monoclonal antibodies targeting CD19 [blinatumomab], or CD22 [inotuzumab ozogamicin]), BCR::ABL1 tyrosine kinase inhibitors (TKIs; e.g., dasatinib, ponatinib), Bruton TKIs (e.g., ibrutinib, acalabrutinib), BCL-2 inhibitors (venetoclax), IDH1/2 inhibitors (ivosidenib, olutasidenib, and enasidenib), FLT3 inhibitors (e.g., midostaurin, quizartinib, and gilteritinib), menin inhibitors (revumenib, ziftomenib), and chimeric antigen receptor T-cell therapies. Herein, we provide a high-level overview of prominent clinical developments across all leukemias. In contemporary times, harnessing the benefits of novel targeted therapies and the evolving treatment landscape bolster the optimistic view that most, if not all, leukemias are curable.

While differentiation therapy revolutionized acute promyelocytic leukemia (APL) with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO), its extension into non-APL AML has been limited until recent targeted agents...IDH1/2 inhibitors (ivosidenib, enasidenib, olutasidenib) yield overall response rates (ORRs) of 30-94% in AML with DS in 10-19%. Menin inhibitors (revumenib, ziftomenib, enzomenib, bleximenib) achieve ORRs of 33-88% in KMT2A-rearranged or NPM1-mutated AML, with DS in 10-25% and QT prolongation as key toxicities. FLT3 inhibitors (gilteritinib, quizartinib) improve survival in FLT3-mutated AML with DS in 1-5%...Improved recognition of DS and rational combination approaches will be essential to maximize the therapeutic benefit. Future research should address mechanisms of resistance and biomarkers to achieve cures beyond APL.

Targeted therapies have improved outcomes in molecularly defined subsets of AML, with menin, IDH and FLT3 inhibitors representing major advances. However, TP53-mutated AML continues to carry a dismal prognosis, underscoring the need for more effective therapeutic strategies. Continued biomarker-driven research, novel drug combinations, and mechanistic insights will be essential to further refine AML treatment and improve long-term survival across disease subsets.

This PMS showed that the safety profile of quizartinib in routine clinical practice in Japanese patients with R/R FLT3-ITD-positive AML did not differ from the known safety profile of quizartinib. QT interval prolongation was manageable with current risk minimization measures.

FLT3 inhibitors - midostaurin (first-generation), gilteritinib and quizartinib (second-generation) - have been developed to block FLT3 activation. The only exception was an higher risk of ALT increased with gilteritinib (RR = 2.40, 95% CI: 1.16-4.95). Future studies should stratify safety outcomes by demographic and clinical characteristics and incorporate long-term follow-up for a more comprehensive safety assessment in clinical practice.

P2/3, N=350, Not yet recruiting, Fundacion PETHEMA

In addition to resistance to cabozantinib, they also exhibited resistance to FDA-approved sorafenib and quizartinib with substantial increases in IC50...Moreover, both omipalisib and radicicol exhibited synergistic effects with cabozantinib, highlighting their therapeutic potential. Overall, we identified metabolic dysregulation as a hallmark of cabozantinib resistance and suggested that targeting metabolic vulnerabilities with PI3K/mTOR or HSP90 inhibitors could be an option to mitigate drug resistance.

Additionally, the quizartinib-induced changes in the intracellular signaling pathways that potentially regulate TRAIL resistance in the AML cells were identified. The identified quizartinib-induced transcriptional changes are of interest not only in the context of combination therapy with TRAIL but also have broader implications for understanding the mechanisms of drug resistance in the AML cells.

Further studies identified compound 1 as a type-I FLT3 inhibitor with comparable potency to quizartinib and gilteritinib; however, compound 1 is much more potent against MV4-11 cells, indicating that it may have a second molecular mechanism of action independent of FLT3 inhibition. Therefore, the high inhibitory potency of compound 1 on MV4-11 cells appear unlikely to be due to synergism of co-inhibition of FLT3 and any other kinases. Altogether, compound 1 may serve as a promising lead compound for further optimization and research on a potentially new molecular antiproliferative mechanism.

P1/2, N=73, Recruiting, M.D. Anderson Cancer Center | Trial completion date: Jan 2026 --> Jan 2028 | Trial primary completion date: Jan 2026 --> Jan 2028

Initial treatment with hydroxyurea and leukapheresis followed by azacitidine and venetoclax resulted in an inadequate treatment response. Given the lack of research on the FLT3 V491L mutation, we conducted an ex vivo sensitivity study using the patient's diagnostic bone marrow blasts to assess and compare the anti-leukemic efficacy of midostaurin, quizartinib, and gilteritinib...Treatment of relapsed AML with a non-canonical mutation is challenging due to the lack of data regarding FLT3 inhibitors. This case highlights the potential role of gilteritinib in targeting the rare FLT3 V491L mutation, underscoring the need for further research and improved accessibility to effective therapies.

In FLT3-internal tandem duplication (FLT3-ITD) AML, FLT3 inhibitors such as quizartinib improve outcomes, but resistance limits long-term efficacy...Finally, analysis of IFNγ signaling and resistance in patient-derived AML blasts revealed variable sensitivity, suggesting the presence of additional compensatory mechanisms. These findings reveal IFNγ signaling as a mechanism of resistance, highlighting a potential therapeutic vulnerability in FLT3-mutated AML.