Partial fatty acid oxidation (pFOX) inhibitor (specifically, a partial inhibitor of long-chain 3-ketoacyl CoA thiolase, 3-KAT). [3]
Nicotinic acid component decreases serum free fatty acid levels. [3]
3-Ketoacyl-CoA thiolase (3-KAT), a key enzyme in the mitochondrial long-chain fatty acid beta-oxidation pathway. Ninerafaxstat is a competitive inhibitor of 3-KAT, which partially inhibits fatty acid oxidation, thereby shifting the heart's energy metabolism towards glucose oxidation.

Ninerafaxstat can effectively alleviate myocardial steatosis, improve left ventricular diastolic filling function, and normalize myocardial energy metabolism.

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In vitro, Ninerafaxstat acts as a potent, cell-permeable inhibitor of fatty acid oxidation by targeting 3-KAT. It reduces fatty acid oxidation and improves overall mitochondrial respiration. This metabolic shift increases glucose oxidation, which provides a greater amount of ATP per molecule of oxygen, thereby improving cardiac metabolic efficiency at the cellular level.

In a murine model of post-MI heart failure (permanent left coronary artery ligation in C57BL/6 male mice), treatment with IMB-1018972 at 30 mg/kg/day from day 1 post-MI (IMM30) significantly increased left ventricular ejection fraction (LVEF) from 38.5±3% (day 1) to 48±4% (week 4; P<0.05), whereas saline-treated mice showed a decrease from 39±2% to 34±2%. Delayed treatment from day 7 post-MI (DEL30) also improved LVEF from 42±1.8% to 48.5±4% (P<0.05). IMM30 mice had lower LV end-diastolic pressure (LVEDP) vs saline (5.3±0.7 vs 7.3±0.6 mmHg; P<0.05) and exhibited markedly less cardiac fibrosis (6.9±0.9 vs 9.7±0.8%; P<0.05), with a trend to lower fibrosis in DEL30 mice (8.3±1.2%). [1]

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In vivo, Ninerafaxstat is orally active. In a mouse model of heart failure after myocardial infarction, it improves left ventricular systolic function, reduces left ventricular end diastolic pressure (LVEDP), and decreases myocardial fibrosis. In the IMPROVE-HCM Phase 2 trial, it was safe and well-tolerated, improving exercise performance and health status in patients with symptomatic nHCM.

For non-cellular enzyme assays, the activity of 3-ketoacyl-CoA thiolase (3-KAT) can be measured in isolated mitochondria or purified enzyme preparations. In these assays, the enzyme is incubated with its substrate (e.g., acetoacetyl-CoA) in the presence of varying concentrations of Ninerafaxstat. The thiolytic cleavage is monitored spectrophotometrically at 303 nm. The inhibition constant (Ki) is calculated from the resulting dose-response curves.

For cell-based assays, cells such as primary cardiomyocytes are treated with Ninerafaxstat (0.1-10 uM) for 24-72 hours. Fatty acid oxidation is measured using radio-labeled fatty acid substrates, and oxygen consumption rates (OCR) are determined using a Seahorse Analyzer. Glucose oxidation can be measured in parallel. The EC50 for shifting substrate utilization is calculated.

Study 1: 12-week-old C57BL/6 male mice underwent permanent left coronary artery ligation or sham surgery. Mice received either saline or IMB-1018972 at 30 mg/kg/day from day 1 post-MI (IMM30), or IMB-101 from day 7 post-MI (DEL30) via osmotic minipump. LV function was assessed by conscious echocardiography at day 1, day 7, and week 4 post-MI, with terminal invasive hemodynamics and cardiac fibrosis quantification using Masson's trichrome staining. [1]

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For animal studies, Ninerafaxstat is administered orally to rodent models of heart failure, e.g., by once-daily dosing (10-30 mg/kg) or via osmotic minipump for continuous delivery over 4 weeks. Cardiac function is assessed by echocardiography and invasive hemodynamics. Tissues (heart, plasma) are harvested to measure fatty acid oxidation rates, cardiac energetics (PCr/ATP ratio by MRS), and fibrosis (by histology).

Ninerafaxstat is orally bioavailable and is typically administered as an oral formulation. It is metabolized in the liver, primarily by the CYP450 enzyme system. It undergoes rapid hydrolysis during enteral absorption and in plasma to liberate IMB-1028814, a structural analogue of trimetazidine. The compound has a favorable half-life supporting once-daily dosing.

Ninerafaxstat was well-tolerated in clinical trials. In IMPROVE-DiCE, one participant stopped treatment early due to frequent diarrhea and withdrew from the trial. In IMPROVE-HCM, treatment-emergent serious adverse events occurred in 11.8% of participants in the ninerafaxstat group vs 6.1% in the placebo group, including COVID pneumonia, angina, pyelonephritis, and diverticular abscess. [3]
In the HPS2-THRIVE trial, high-dose nicotinic acid (2g daily) with laropiprant increased the risk of myopathy when added to simvastatin. However, ninerafaxstat is administered at a lower fixed dose combination (200mg) and was well-tolerated without significant side effects. [3]

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In clinical Phase 2 trials, Ninerafaxstat has been well-tolerated, with no significant safety concerns or serious adverse events reported at the 200 mg once-daily dose. Reported adverse events include COVID, CABG, pyelonephritis, and abdominal abscess in the treatment arm. According to safety data sheets, the compound is irritating to skin and eyes and may be toxic if swallowed.

[[1]. IMB-1018792, A NOVEL FIRST-IN CLASS PARTIAL FATTY ACID OXIDATION INHIBITOR IMPROVES CARDIAC REMODELING AND FUNCTION POST-MYOCARDIAL INFARCTION. J Am Coll Cardiol. 2021 May 11;77(18):539.

[2]. Kiosk 11R-TC-08 - Ninerafaxstat Modulates Cardiac Energy Metabolism in Cardio-metabolic Syndromes: A Mechanistic, Hyperpolarized MR Trial. Journal of Cardiovascular Magnetic Resonance. 2024; 26: 100325.

[3]. Ninerafaxstat in the Treatment of Diabetic Cardiomyopathy and Nonobstructive Hypertrophic Cardiomyopathy. Cardiol Rev. 2024 Aug 28. doi: 10.1097/CRD.0000000000000776.

[4]. Abstract 10372: A Clinical Drug-Drug Interaction Study of Imb-1018972, a Novel Investigational Cardiac Mitotrope in Phase 2 Development for the Treatment of Myocardial Ischemia and Hypertrophic Cardiomyopathy. METABOLISM AND PHYSIOLOGY. 8 Nov 2021.

Mechanism: By partially inhibiting fatty acid oxidation, ninerafaxstat shifts myocardial metabolism toward glucose, increasing PDH activity and the efficiency of energy generation (glucose yields more ATP per O2 consumption than FA). The nicotinic acid component decreases serum FFA levels, thereby increasing myocardial glucose uptake and oxidation via PDH. [1][3]
Clinical Trial - IMPROVE-DiCE (NCT04826159): A single-center, open-label, phase 2a trial in 21 patients with type 2 diabetes and obesity. Patients received 200mg ninerafaxstat twice daily for 4 (n=5) or 8 weeks (n=16). Inclusion: T2D, HbA1C ≥6.5, age 18-75, BMI ≥30 kg/m², LVEF ≥50%. Primary outcome: resting ³¹P-MRS PCr/ATP ratio. Ninerafaxstat significantly increased PCr/ATP median from 1.6 (IQR 1.4,2.1) to 2.1 (IQR 1.7,2.5) (P<0.01), reduced myocardial triglyceride content by 34% (P=0.026), improved LV peak circumferential diastolic strain rate by 15% (P<0.047), and peak LV filling rate by 11% (P<0.05). PDH flux (bicarbonate/pyruvate ratio) increased by 20% (P=0.08), with 7/9 participants showing an increase. Body weight reduction of 1.5kg (P<0.01), total cholesterol (P=0.052), and LDL cholesterol (P=0.01) were observed. [2][3]
Clinical Trial - IMPROVE-HCM (NCT04826185): A phase 2, multicenter, randomized, double-blind, placebo-controlled study in patients with nonobstructive hypertrophic cardiomyopathy. Patients received ninerafaxstat 200mg twice daily or placebo for 12 weeks. Ninerafaxstat significantly improved ventilatory efficiency (VE/VCO2) slope compared to placebo (P=0.006). In a post hoc analysis of 35 patients with baseline KCCQ score ≤80, changes in VE/VCO2 slope favored ninerafaxstat vs placebo (P=0.02). Left atrial size was significantly decreased vs placebo (P=0.01). A greater proportion of patients on ninerafaxstat had KCCQ score improvements of ≥5 (57% vs 44%), ≥10 (38% vs 33%), and ≥20 points (19% vs 6%) compared with placebo. [3]

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Ninerafaxstat is a novel cardiac mitotrope developed by Imbria Pharmaceuticals. It was in Phase 2 clinical trials for several cardiometabolic indications, including nHCM (IMPROVE-HCM), obstructive coronary artery disease (IMPROVE-Ischemia), and HFpEF (IMPROVE-DiCE). It is currently not approved by any regulatory agency for clinical use and is intended for research purposes.

C22H32CL3N3O5

524.8655834198

523.14

C, 50.34; H, 6.15; Cl, 20.26; N, 8.01; O, 15.24

2311824-72-1

Ninerafaxstat;2254741-41-6

155801579

White to off-white solid powder

3

8

10

33

515

0

Cl.Cl.Cl.O(C(C1C=NC=CC=1)=O)CCN1CCN(CC2C=CC(=C(C=2OC)OC)OC)CC1

XDBODYSZDLGFRQ-UHFFFAOYSA-N

InChI=1S/C22H29N3O5.3ClH/c1-27-19-7-6-18(20(28-2)21(19)29-3)16-25-11-9-24(10-12-25)13-14-30-22(26)17-5-4-8-23-15-17;;;/h4-8,15H,9-14,16H2,1-3H3;3*1H

2-[4-[(2,3,4-trimethoxyphenyl)methyl]piperazin-1-yl]ethyl pyridine-3-carboxylate;trihydrochloride

Ninerafaxstat trihydrochloride; IMB-1018972 trihydrochloride; IMB-101 hydrochloride; IMB 1018972 trihydrochloride; IMB101; IMB1018972; IMB-101;Ninerafaxstat 3HCl; Ninerafaxstat HCl; Ninerafaxstat hydrochloride;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

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

DMSO: 41.67 mg/mL (79.39 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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