Synergistic Strategies for KMT2A-Rearranged Leukemias: Beyond Menin Inhibitor.

The KMT2A-PTD oncoprotein depends on ENL but not menin to drive AML gene expression

Pharmacologic targeting of the menin-KMT2A protein-protein interaction has emerged as a therapeutic breakthrough for acute leukemias harboring KMT2A rearrangements or NPM1 mutations. The first-in-class menin inhibitor (revumenib) achieved accelerated regulatory approval in November 2024 for monotherapy of relapsed/refractory KMT2A rearranged leukemia. Next-generation agents (ziftomenib, bleximenib, enzomenib, BMF-219) have displayed similar composite complete remission rates (20-35%) and overall response rates (45-65%) in heavily pretreated KMT2Ar and NPM1m acute myeloid leukemia (AML) with measurable residual disease (MRD) negativity and prolonged overall survival (5-7 months). While all menin inhibitors result in on-target blast differentiation with clinical sequelae ("differentiation syndrome") in 10% to 20% of patients, not all menin inhibitors are the same, with differing safety, toxicity (heartrate corrected QT interval (QTc) prolongation, cytopenias), and pharmacokinetic profiles. Acquired mutations in the menin gene described in 39% of post-revumenib relapses have not been identified following other inhibitors (ziftomenib, bleximenib), prompting new questions about resistance mechanisms. These promising results swiftly led to the launch of multiple trials of menin inhibitors combined with intensive (cytarabine and anthracycline) and nonintensive (venetoclax and hypomethylating) chemotherapy backbones. To date, these triplets have yielded high response rates (ie, ≥80% in de novo, 50-70% in relapsed) with most patients achieving MRD negativity and prolonged one-year survival. Ongoing/pending phase 3 trials will clarify whether menin blockade should be incorporated into frontline and maintenance regimens for all patients with KMT2A rearranged or NPM1 mutant disease. In the current era, menin inhibition remains a key pillar of the success of precision medicine for AML therapy.

Therapeutic effect of menin inhibitors is reversible in AML treatment and could be enhanced by the targeting of differentiation associated chromatin complex

Upfront menin-inhibitor resistance in multiply pretreated leukemias.

A first-in-class oral clinical candidate targeting MLLT1 and 3 degradation for the treatment of advanced AML and ALL including menin inhibitor resistant / refractory disease

Menin, encoded by the MEN1 gene, is a scaffold protein widely expressed in human tissues, regulating diverse functions through interactions in key signaling pathways. The menin-MLL1 (KMT2A) complex plays a critical role in acute leukemias with KMT2A rearrangements or NPM1 mutations, driving aberrant expression of HOX genes and MEIS1, which promote leukemia development. MLL is a histone H3K4 methyltransferase essential for transcription in embryonic development and hematopoiesis and frequently forms oncogenic fusion proteins via chromosomal translocations. Disrupting the menin-MLL interaction is an effective therapeutic strategy for MLL-rearranged and NPM1-mutant leukemias. The FDA-approved menin inhibitor SNDX-5613 treats relapsed/refractory acute leukemia with MLL translocations, while ongoing trials explore its use in KRAS-mutant solid tumors and Wnt-driven cancers. Another menin inhibitor, KO-539, is being tested in advanced gastrointestinal stromal tumors. Developing novel menin inhibitors with enhanced safety and efficacy remains a significant clinical priority. Herein, we report RCZY-711, a novel, highly potent, and orally bioavailable menin inhibitor with subnanomolar binding affinity, as demonstrated by SPR. Its potency in disrupting the menin-MLL interaction was further validated using a fluorescence polarization assay (subnanomolar IC50). RCZY-711 displayed potent growth inhibition (single-digit nanomolar IC50) in cancer cell lines with KMT2A rearrangements or NPM1 mutations, without cytotoxicity in wild-type MLL cell lines. The compound demonstrated desirable drug-like in vitro ADME characteristics, clean in vitro safety characteristics (hERG IC50 > 20 µM), and excellent pharmacokinetic characteristics across multiple preclinical species. Oral treatment with RCZY-711 also showed strong in vivo anti-tumor efficacy in acute myeloid leukemia xenograft mouse models, including the MV-4-11 xenograft model with the MLL-AF4 fusion. The observed superior in vivo efficacy may be attributed to its high cellular potency and improved half-life (mouse: T1/2 = 2.0 h). In conclusion, RCZY-711 is a novel, highly potent and orally bioavailable menin-MLL inhibitor with best-in-class clinical potential for treating MLL-rearranged and NPM1-mutant acute leukemias. Citation Format: Celia X.-J. Chen, Zhengyong Wan, Yu Bai, Xiaohong Liu, Jianming Bao. RCZY-711, a novel, highly potent, and orally bioavailable menin-MLL inhibitor with superior efficacy in preclinical acute leukemia models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1419.

Introduction: KRAS (Kirsten rat sarcoma virus) is the most frequently mutated isoform amongst RAS oncogenes in human solid tumors being present in a high percentage of colorectal cancers (CRC), non-small cell lung cancers (NSCLC), and pancreatic cancers. With only one approved KRAS G12C inhibitor for NSCLC, KRAS-driven tumors continue to represent a significant unmet medical need where novel effective therapies are highly desired. Menin is a required co-factor of oncogenic transcriptional proteins with functional interactions that are critical for various malignancies including acute leukemia. We previously reported that BMF-219, a novel irreversible menin inhibitor, exhibits strong potency on acute leukemia (MOLM-13) and KRAS-mutant (MiaPaCa-2) cells. Results from MiaPaCa-2 cells prompted our exploration of the effects of BMF-219 in an expanded panel of KRAS-mutant solid tumors through in vitro and ex vivo preclinical models. Methods: BMF-219, clinical reversible menin inhibitors, or clinically approved KRAS G12C inhibitor, sotorasib, were cultured with CRC, NSCLC, pancreatic cancer cell lines for 4-days. Human ex vivo preclinical models harboring KRAS mutations were cultured with BMF-219 and reversible menin for 6-days. Cell viability was measured using CellTiter Glo and IC50 values were calculated. MiaPaCa-2 cells incubated with BMF-219 were analyzed by RNA-seq on the Illumina NextSeq 550 platform. Results: MiaPaCa-2, a KRAS G12C-mutant cell line, showed marked reduction of KRAS expression levels following 24 hours of BMF-219 treatment at 0.5 µM. An expanded panel of 14 CRC, NSCLC and pancreatic KRAS-mutant cell lines harboring G12C, G12D, G12V, and Q61L revealed single-agent BMF-219 activity after a 4-day treatment. Majority of the cell lines tested exhibited >90% inhibition of growth, independent of KRAS mutation type. Sotorasib reached a maximum of 90-93% growth inhibition in three of eight cell lines. By contrast, BMF-219 inhibited cell viability ≥ 90% in six of eight KRAS G12C lung cancer lines. Human CRC, NSCLC and pancreatic ex vivo preclinical models with G12C, G12D, and G12V KRAS mutations were all sensitive to BMF-219 after a 6-day treatment. Complete abrogation of growth was observed in all samples with IC50 values ranging between 0.2 μM - 0.6 μM. Conclusion: KRAS-mutant CRC, NSCLC, pancreatic cancer cell lines and ex vivo preclinical models are highly sensitive to irreversible menin inhibitor, BMF-219, where clinical reversible menin inhibitors displayed limited activity. High potency of BMF-219 was observed amongst various KRAS-mutant cell lines suggesting that BMF-219 broadly inhibits these tumors. As an irreversible menin inhibitor, BMF-219, manifests advantages over the KRAS-targeted inhibitor sotorasib in multiple cell lines tested, and displays unique potency compared with clinical reversible menin inhibitors in ex vivo preclinical models of CRC, NSCLC, and pancreatic cancer. Citation Format: Brian Law, Daniel Lu, Priyanka Somanath, James T. Palmer, Taisei Kinoshita, Thomas Butler. Irreversible menin inhibitor, BMF-219, inhibits the growth of KRAS-mutated solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2665.

The Clinical Menin Inhibitor Ziftomenib and the Nuclear Export Inhibitor Selinexor Synergistically Inhibit the Growth of MLL-r AML

In MLL1-rearranged AML (MLL1-r), the MLL1 fusion protein (MLL-FP) causes dysregulated expression of HOXA9, MEIS1, PBX3, MEF2C and CDK6 HOXA9 and its co-factor MEIS1 are leukemogenic in myeloid stem progenitor cells Additionally, in AML with mtNPM1 (NPM1c), MLL1 is the main oncogenic regulator of HOXA9, MEIS1 and FLT3, promoting self-renewal of myeloid progenitor cells Orally bioavailable, investigational or clinical drug candidate Menin inhibitors (MIs) disrupt binding of Menin to its binding pocket in MLL1/2 and MLL1-FP, which reduces MLL1/2 and MLL1-FP binding to their targets, inhibits HOXA9/MEIS1 activity, represses PBX3, MEF2C, FLT3 and CDK6, as well as induces differentiation and loss of survival of AML with MLL1-r or with mutant (mt)-NPM1 [2, 8-10]. In early clinical trials, monotherapy with MI is well tolerated and has achieved objective remissions in patients with previously treated relapsed/ refractory AML harboring MLL1-r or NPM1c However, most patients either fail to respond or eventually relapse Therefore, there is a need to investigate the activity of additional MIs and MIbased combinations that may exhibit superior activity and prevent or abrogate MI-resistance in AML cells with MLL1-r or mtNPM1.

Translocations of Meningioma-1 (MN1) occur in a subset of acute myeloid leukemias (AML) and result in high expression of MN1, either as a full-length protein, or as a fusion protein that includes most of the N-terminus of MN1. High levels of MN1 correlate with poor prognosis. When overexpressed in murine hematopoietic progenitors, MN1 causes an aggressive AML characterized by an aberrant myeloid precursor-like gene expression program that shares features of KMT2A-rearranged (KMT2A-r) leukemia, including high levels of Hoxa and Meis1 gene expression. Compounds that target a critical KMT2A–Menin interaction have proven effective in KMT2A-r leukemia. Here, we demonstrate that Menin (Men1) is also critical for the self-renewal of MN1-driven AML through the maintenance of a distinct gene expression program. Genetic inactivation of Men1 led to a decrease in the number of functional leukemia-initiating cells. Pharmacologic inhibition of the KMT2A–Menin interaction decreased colony-forming activity, induced differentiation programs in MN1-driven murine leukemia and decreased leukemic burden in a human AML xenograft carrying an MN1-ETV6 translocation. Collectively, these results nominate Menin inhibition as a promising therapeutic strategy in MN1-driven leukemia.

Intensified Conditioning Containing Decitabine Versus Standard Myeloablative Conditioning for Adult Patients with KMT2A-Rearranged Leukemia: A Multicenter Retrospective Study

Preliminary data from the ongoing Phase 1 study of the menin-MLL inhibitor enzomenib (DSP-5336) in combination with venetoclax and azacitidine in patients with relapsed or refractory Acute Myeloid Leukemia

High-throughput proteomic profiling provides a comprehensive analysis of systemic cancer effects and tumor microenvironment interactions. Characterizing soluble proteins driving inflammation in acute myeloid leukemia (AML) offers insight into inflammatory diseases like differentiation syndrome related to AML therapies like menin inhibitors. We present our application of nucleic acid-linked immuno-sandwich assay, a novel technology leveraging next-generation sequencing for high-throughput, ultrasensitive characterization of secreted inflammatory proteins in plasma or serum. Here, we report its use to identify dynamic soluble protein changes during treatment and at the time of suspected differentiation syndrome in pediatric AML patients treated with the menin inhibitor revumenib (NCT04065399 and NCT05360160).

AML-298: Menin Inhibitors in KMT2A-Rearranged and NPM1-Mutated Acute Leukemia: A Scoping Review of Safety and Efficacy

Background: BMF-219 is a selective covalent inhibitor of menin, a transcriptional regulator of oncogenic signaling pathways in multiple cancers, that inhibits the menin/MYC interaction and downregulates the expression of MYC and MYC target genes, including KRAS. Mechanism of Action (hypothesis): In addition to MYC disruption, inhibition of the Menin-MLL complex by BMF-219 alters JunD genomic function, a crucial factor for KRAS-driven tumorigenesis. Inhibition of the Menin-MLL complex suppresses expression of Rasgrf1, which is essential for generation of the active RAS-GTP conformation of KRAS, activation of downstream pathways, and tumorigenesis. Preclinically, BMF-219 shows sustained potent abrogation of menin-dependent oncogenic signaling. BMF-219 exerts pan-mutant KRAS anticancer activity that is independent of the specific KRAS-activating mutation. Methods: COVALENT-102 (NCT05631574) is a prospective, open-label, multicenter, dose finding study evaluating the safety, tolerability, and clinical activity of escalating doses of BMF-219 administered daily in patients with unresectable, locally advanced, or metastatic NSCLC (Cohort 1), PDAC (Cohort 2) & CRC (Cohort 3) with activating KRAS mutations who have received standard therapy. All indications as a group will follow a 3+3 dose escalation design. BMF-219 will be administered orally daily as continuous therapy as 28-days treatment cycle until progression or intolerability/unacceptable toxicity. Following conclusion of the dose-escalation, each indication will enroll patients in expansion cohorts independently to obtain further safety and efficacy data. Eligible patients include those with any KRAS mutation & (Cohort 1) stage IIIB/IV NSCLC with 2-4 prior lines of therapy including immune checkpoint inhibitors (ICI) &/or platinum-based chemo ± bevacizumab with ECOG PS 0-2; (Cohort 2) stage III/IV PDAC with ≥ 1 prior line of therapy including either FOLFIRINOX or gemcitabine/nab-paclitaxel, ECOG PS 0-1; or (Cohort 3) stage III/IV CRC with ≥ 1 prior line of therapy including FOLFOX or FOLFIRI ± bevacizumab (prior ICI if MSI-H/dMMR), ECOG PS 0-2. Patients must have documented progression & measurable disease as defined by RECIST 1.1. Patients with prior KRAS inhibitor exposure are eligible. Key exclusion criteria include symptomatic &/untreated CNS metastasis, prior menin inhibitor therapy, and clinically significant cardiovascular disease. The primary objective is to determine the optimal biological dose (OBD)/recommended Phase 2 dose (RP2D) of BMF-219 monotherapy. Secondary objectives include further evaluation of safety & tolerability, characterization of the pharmacodynamics and pharmacokinetics of BMF-219, and efficacy based on duration of response (DOR) & disease control rate (DCR). Assessment of progression-free survival (PFS), overall survival (OS) & time to response (TTR) are part of the exploratory endpoints. The first patient in the study is anticipated to be dosed in Q4 of 2022. Citation Format: Stacey A. Cohen, Christos Fountzilas, David Sommerhalder, Sandip Patel, Ai Benson, Kai He, Apar Ganti, Alex Spira, Bhagyashree (Kelshikar) Yadav, Alex Cacovean, Steve Morris, Tom Butler, David Hong. COVALENT-102: A phase 1/1b dose finding study of BMF-219, an oral covalent menin inhibitor, in patients with metastatic non-small cell lung cancer (NSCLC), pancreatic cancer (PDAC), and colorectal cancer (CRC) with activating KRAS mutations [abstract]. In: Proceedings of the AACR Special Conference: Targeting RAS; 2023 Mar 5-8; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Res 2023;21(5_Suppl):Abstract nr A003.