BAY-1436032 is a brand-new pan-mutant inhibitor of isocitrate dehydrogenase 1 (IDH1). In mouse hematopoietic cells expressing IDH1R132H or IDH1R132C, BAY-1436032 reduces intracellular (R)-2-hydroxyglutarate (R-2HG) synthesis with IC50 values of 60 and 45 nM, respectively. Even at dosages up to 10 μM, BAY-1436032 does not lower R-2HG levels in mouse hematopoietic cells expressing IDH2R140Q and IDH2R172K. At doses as high as 100 μM, BAY-1436032 did not impede the colony expansion of patient-derived IDH1 wild-type AML cells, but it did at 50% when it came to that growth. BAY-1436032 significantly enhanced myelomonocytic differentiation of myeloid progenitor cells in morphological assessment [1].

BAY-1436032 is a brand-new pan-mutant inhibitor of isocitrate dehydrogenase 1 (IDH1). In mouse hematopoietic cells expressing IDH1R132H or IDH1R132C, BAY-1436032 reduces intracellular (R)-2-hydroxyglutarate (R-2HG) synthesis with IC50 values of 60 and 45 nM, respectively. Even at dosages up to 10 μM, BAY-1436032 does not lower R-2HG levels in mouse hematopoietic cells expressing IDH2R140Q and IDH2R172K. At doses as high as 100 μM, BAY-1436032 did not impede the colony expansion of patient-derived IDH1 wild-type AML cells, but it did at 50% when it came to that growth. BAY-1436032 significantly enhanced myelomonocytic differentiation of myeloid progenitor cells in morphological assessment [1].

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BAY-1436032 selectively inhibited intracellular R-2HG production in immortalized mouse hematopoietic cells engineered to express IDH1R132H (IC₅₀ 60 nM) or IDH1R132C (IC₅₀ 45 nM). [1]
BAY-1436032 potently inhibited R-2HG production in primary human AML cells carrying various IDH1R132 mutations (IC₅₀ between 3 and 16 nM) but had virtually no effect on IDH2 mutant cells at concentrations up to 1 μM. [1]
BAY-1436032 inhibited colony formation of primary human IDH1 mutant AML cells in methylcellulose-based clonogenic assays, with approximately 50% inhibition at 0.1 μM. Colony growth of IDH1 wild-type AML cells was not suppressed even at 100 μM. [1]
BAY-1436032 induced myeloid differentiation in primary IDH1 mutant AML cells cultured ex vivo, as evidenced by upregulation of the surface differentiation markers CD14 and CD15, and by morphological changes showing monocytic/granulocytic maturation. [1]
BAY-1436032 treatment (500 nM, 14 days) reduced global histone H3 trimethylation levels at residues H3K4, H3K9, H3K27, and H3K36 in primary IDH1R132C and IDH1R132H mutant AML cells, but not in IDH1 wild-type cells. [1]
DNA methylation analysis using the Illumina Infinium HumanMethylation450 platform showed that BAY-1436032 treatment (500 nM, 14 days) altered specific methylation patterns, including decreased methylation of the PLU1 promoter and increased methylation of the E2F1 promoter in IDH1 mutant AML cells. [1]

At 150 mg/kg, long-term oral treatment of BAY-1436032 once daily showed nearly total suppression of (R)-2-hydroxyglutarate (R-2HG) synthesis. White blood cell counts in mice given vehicle treatment climbed steadily; in mice given 45 mg/kg BAY-1436032, the rate of increase was slowed; and in the 150 mg/kg group, the numbers were unchanged. Day 60 hemoglobin levels were marginally lower in the vehicle group and 45 mg/kg group than in the 150 mg/kg group, while the mice treated with BAY-1436032 at 45 mg/kg group and the vehicle group had marginally lower hemoglobin levels than the animals in the 150 mg group. Day 60 saw a significant reduction in the cohort's platelet count/kg. While animals treated with vehicles died, all mice given 150 mg/kg BAY-1436032 survived and had the lowest hCD45+ cell load in the peripheral blood until the end of observation on day 150 after the start of therapy (P<0.001). Bits have a 91-day lifespan. A 45 mg/kg dose of BAY-1436032 produced moderately expressed CD14/CD15 in mice [1].

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In a patient-derived xenograft (PDX1) mouse model of IDH1R132C mutant AML, once-daily oral administration of BAY-1436032 at 150 mg/kg for 150 days starting 17 days post-transplantation led to sustained suppression of serum R-2HG levels, significant reduction of human CD45⁺ (hCD45⁺) leukemic blasts in peripheral blood, and prolonged survival (all mice survived until day 150, compared to median survival of 91 days in vehicle group). [1]
In a second independent PDX model (PDX2) of IDH1R132C mutant AML with an MLL-PTD co-mutation, treatment with BAY-1436032 (150 mg/kg once daily, starting 90 days post-transplantation) for 100 days suppressed serum R-2HG, reduced peripheral hCD45⁺ blast counts, and significantly prolonged survival (6 of 10 mice survived until treatment stop at day 100, median survival not reached vs. 62 days in vehicle group). [1]
BAY-1436032 induced myeloid differentiation of leukemic cells in vivo, as shown by increased proportions of hCD45⁺ cells expressing CD14 and CD15, and decreased proportions of CD34⁺ progenitor cells in peripheral blood of treated PDX mice. [1]
BAY-1436032 depleted leukemic stem cells (LSCs) in vivo. Limiting dilution transplantation experiments showed a ~100-fold reduction in LSC frequency in bone marrow cells from mice treated with BAY-1436032 (150 mg/kg) compared to vehicle-treated mice. [1]
Gene expression profiling of hCD45⁺ cells from treated PDX mice revealed downregulation of stemness-associated genes (e.g., SPARC, CD69, DNMT3B) and upregulation of myeloid differentiation and immune response genes. Cell cycle analysis showed an increase of hCD45⁺ cells in G₀/G₁ phase and a decrease in S phase upon BAY-1436032 treatment. [1]

To assess inhibition of R-2HG production, HoxA9-immortalized mouse bone marrow cells retrovirally transduced with mutant IDH1 or IDH2 were treated with BAY-1436032 or DMSO for 8 days. Cells were harvested, and the ratio of R-2HG to S-2-hydroxyglutarate (S-2HG) in cell lysates was measured by mass spectrometry. [1]
Primary human AML cells freshly isolated from patients were treated with BAY-1436032 or DMSO for 24 hours. The R-2HG to S-2HG ratio in cell lysates was measured to determine IC₅₀ values. [1]
For clonogenic progenitor assays, primary human AML mononuclear cells were plated in methylcellulose medium supplemented with cytokines and either BAY-1436032 or vehicle. Colonies were counted microscopically after 10-14 days. [1]
To evaluate differentiation, primary IDH1 mutant AML cells were cultured in suspension medium with BAY-1436032 or DMSO for several days. Cells were then analyzed by flow cytometry for expression of CD14 and CD15, and morphologically assessed on cytospin preparations after staining. [1]
For histone methylation analysis, primary AML cells were treated with 500 nM BAY-1436032 or DMSO for 14 days. Histones were extracted, and global levels of H3K4me3, H3K9me3, H3K27me3, and H3K36me3 were analyzed by Western blotting, with quantification of band intensities relative to total histone H3. [1]

For pharmacokinetic and pharmacodynamic studies, mice were administered BAY-1436032 orally by gavage at doses of 45, 90, or 150 mg/kg. Blood was collected at various time points to measure plasma drug concentrations and serum R-2HG levels. [1]
For efficacy studies in PDX models, NOD-scid IL2Rγnull (NSG) mice were transplanted intravenously with primary human IDH1 mutant AML cells. Once engraftment was established (as measured by hCD45⁺ cells in peripheral blood), treatment was initiated. [1]
In the PDX1 model, treatment started 17 days post-transplantation. Mice (n=10 per group) received vehicle, 45 mg/kg, or 150 mg/kg BAY-1436032 by oral gavage once daily for 150 days. [1]
In the PDX2 model, treatment started 90 days post-transplantation to mimic a higher disease burden. Mice (n=10 per group) received vehicle or 150 mg/kg BAY-1436032 by oral gavage once daily for 100 days, after which treatment was stopped and mice were monitored for relapse. [1]
Mice were monitored for survival, body weight, and peripheral blood counts. Peripheral blood was periodically analyzed by flow cytometry for hCD45⁺ cells and differentiation markers (CD14, CD15, CD34, CD33). Serum R-2HG levels were measured by mass spectrometry or enzymatic assay. [1]
For limiting dilution assays to assess LSC frequency, bone marrow cells were harvested from PDX mice treated with vehicle or BAY-1436032 (150 mg/kg) for 4 weeks. Serially diluted cells were transplanted into secondary NSG recipients, and engraftment was assessed to calculate LSC frequency using Poisson statistics. [1]

In mice, plasma exposure to BAY-1436032 was almost dose-linear in the range of 45 to 150 mg/kg. [1]
Within 24 hours after administration, free plasma concentrations covered the IC₅₀ value for R-2HG inhibition in vitro. [1]
Oral administration of BAY-1436032 resulted in a rapid decrease in serum R-2HG levels, detectable as early as 3 hours after administration. [1]
Long-term once-daily oral administration of 150 mg/kg BAY-1436032 almost completely inhibited R-2HG production in PDX mice. [1]

[1]. Pan-mutant-IDH1 inhibitor BAY1436032 is highly effective against human IDH1 mutant acute myeloid leukemia in vivo. Leukemia. 2017 Oct;31(10):2020-2028.

The panmutant IDH1 inhibitor Bay-1436032 is an orally administered panmutant inhibitor that inhibits mutant forms of the metabolic enzyme isocitrate dehydrogenase type 1 (IDH1; IDH-1; IDH1 [NADP+] soluble), including IDH1 with the arginine 132 mutation (IDH1(R132)), and possesses potential antitumor activity. After administration, the panmutant IDH-1 inhibitor Bay-1436032 specifically inhibits the activity of IDH1 mutants, thereby preventing the formation of the oncogenic metabolite 2-hydroxyglutarate (2HG) from α-ketoglutarate (α-KG). This blocks 2HG-mediated signaling, leading to enhanced differentiation and inhibited proliferation of tumor cells expressing IDH1 mutants. IDH1 mutations, including the IDH1(R132) mutation, are highly expressed in certain malignancies; they initiate and drive cancer growth by blocking cell differentiation and catalyzing the production of 2-hydroxyglutarate (2HG).

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BAY-1436032 is a novel, orally bioavailable panmutant IDH1 inhibitor designed to target all major IDH1R132 mutations found in cancer. [1]
Its mechanism of action involves inhibiting the novel functional activity of mutant IDH1, thereby reducing the production of the oncogenic metabolite R-2HG. This leads to reversal of histone and DNA hypermethylation, relief of differentiation arrest, proliferation inhibition, and depletion of leukemia stem cells. [1]
This study demonstrates that BAY-1436032 is highly effective in vivo against human IDH1-mutant acute myeloid leukemia, clearing primitive cells, promoting cell differentiation, and prolonging survival in a preclinical PDX model. [1]
Based on this preclinical study, at the time of publication, a Phase I clinical trial in patients with IDH1R132-mutant AML is underway. [1]

C26H30F3N3O3

489.529917240143

489.22

C, 63.79; H, 6.18; F, 11.64; N, 8.58; O, 9.80

1803274-65-8

118310260

White to gray solid powder

7.2

2

8

7

35

726

2

C[C@H]1C[C@H](CC(C1)(C)C)N2C3=C(C=C(C=C3)CCC(=O)O)N=C2NC4=CC=C(C=C4)OC(F)(F)F

RNMAUIMMNAHKQR-QFBILLFUSA-N

InChI=1S/C26H30F3N3O3/c1-16-12-19(15-25(2,3)14-16)32-22-10-4-17(5-11-23(33)34)13-21(22)31-24(32)30-18-6-8-20(9-7-18)35-26(27,28)29/h4,6-10,13,16,19H,5,11-12,14-15H2,1-3H3,(H,30,31)(H,33,34)/t16-,19+/m0/s1

3-(2-((4-(trifluoromethoxy)phenyl)amino)-1-((1R,5R)-3,3,5-trimethylcyclohexyl)-1H-benzo[d]imidazol-5-yl)propanoic acid

BAY-1436032; BAY 1436032; BAY1436032.

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~125 mg/mL (~255.35 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.11 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 2.5 mg/mL (5.11 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (5.11 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)