Absorption, Distribution, Metabolism And Excretion Research Articles

Synthesis, Characterization, and Pharmacokinetic Studies of Thiazolidine-2,4-Dione Derivatives

Various derivatives of thiazolidine-2,4-dione (C1–C5) were designed and synthesized by chemical reaction with 4-nitrobenzaldehyde using Knoevenagel reaction conditions which results in the reduction of nitro group to amine and further modification results in target compounds. The chemical structures of all the 2,4-thiazolidinedione derivatives have been elucidated by 1H and 13C NMR spectroscopy. These compounds were further characterized by in silico ADME (absorption, distribution, metabolism, and excretion) studies. The pharmacokinetic properties were assessed by SwissADME software. The in silico ADME (absorption, distribution, metabolism, and excretion) assessment reveals that all derivatives (C1 to C5) have 5 to 7 rotatable bonds. Lipophilicity and water solubility showed that C1, C2, and C4 are water soluble except for C3 and C5 which are moderately soluble. All the compounds have high GI absorption except C3. None of the derivatives are blood-brain barrier permeant. Drug metabolism of TZDs derivatives showed that C3 was identified as an inhibitor of CYP2C9 and C5 as an inhibitor of CYP1A2 and CYP2C19. Drug likeness properties indicate that C1 has only one violation of the Ghose rule while C3 has violations in the Ghose and Egan rules. The in silico pharmacokinetic studies revealed high GI absorption and the inability to pass blood-brain barrier which can be further assessed by in vitro and in vivo antihyperglycemic activity. This study will contribute to providing TZDs derivatives with an improved pharmacokinetic profile and decreased toxicity.

Integrative Ligand-Based Pharmacophore Modeling, Virtual Screening, and Molecular Docking Simulation Approaches Identified Potential Lead Compounds against Pancreatic Cancer by Targeting FAK1

Pancreatic cancer is a very deadly disease with a 5-year survival rate, making it one of the leading causes of cancer-related deaths globally. Focal adhesion kinase 1 (FAK1) is a ubiquitously expressed protein in pancreatic cancer. FAK, a tyrosine kinase that is overexpressed in cancer cells, is crucial for the development of tumors into malignant phenotypes. FAK functions in response to extracellular signals by triggering transmembrane receptor signaling, which enhances focal adhesion turnover, cell adhesion, cell migration, and gene expression. The ligand-based drug design approach was used to identify potential compounds against the target protein, which included molecular docking: ADME (absorption, distribution, metabolism, and excretion), toxicity, molecular dynamics (MD) simulation, and molecular mechanics generalized born surface area (MM-GBSA). Following the retrieval of twenty hits, four compounds were selected for further evaluation based on a molecular docking approach. Three newly discovered compounds, including PubChem CID24601203, CID1893370, and CID16355541, with binding scores of -10.4, -10.1, and -9.7 kcal/mol, respectively, may serve as lead compounds for the treatment of pancreatic cancer associated with FAK1. The ADME (absorption, distribution, metabolism, and excretion) and toxicity analyses demonstrated that the compounds were effective and nontoxic. However, further wet laboratory investigations are required to evaluate the activity of the drugs against the cancer.

2,4-Diamino-5-(5-hydroxy-1-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-5H-chromeno[2,3-b]pyridine-3-carbonitrile

5H-Chromeno[2,3-b]pyridines are important compounds with industrial, biological, and medicinal properties. In this short note, the multicomponent reaction of salicylaldehyde, malononitrile dimer, and 2-phenyl-5-(trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one in dimethyl sulfoxide at ambient temperature was investigated to give 2,4-diamino-5-(5-hydroxy-1-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-5H-chromeno[2,3-b]pyridine-3-carbonitrile with good yield. The structure of the previously unknown chromeno[2,3-b]pyridine derivative was confirmed by elemental analysis, mass, nuclear magnetic resonance, and infrared spectroscopy data. The ADME (absorption, distribution, metabolism, and excretion) properties were also assessed.

In vitro antitumor activity, molecular dynamics simulation, DFT study, ADME prediction, and Eg5 binding of enastron analogues.

The objective of this study is to evaluate a series of molecules based on cyclosulfamide as potential anticancer agents. Additionally, the study aims to analyze the obtained results through in silico studies; by conducting experiments and utilizing theoretical methods. In this context, we investigated the cytotoxic activity of enastron analogues on three human cell lines PRI (lymphoblastic cell line) derived from B-cell lymphoma. JURKAT (ATCC TIB-152) acute T cell leukaemia and K562 (ATCC CLL-243) is a chronic myelogenous leukaemia. Most of the tested compounds showed good inhibitory activity compared with the reference ligand (chlorambucil). The 5a derivative demonstrated the strongest effect against all cancer cells used. Furthermore, molecular docking simulations of the Eg5-enastron analogue complex revealed that studied molecules have the ability to inhibit the Eg5 enzyme, as evidenced by their calculated docking score. Following the promising results from the molecular docking study, the complex Eg5-4a underwent a 100 ns molecular dynamics simulation using Desmond. During the simulation, the receptor-ligand pairing demonstrated substantial stability after the initial 70 ns. In addition, we used DFT calculations to analyze the electronic and geometric characteristics of the studied compounds. The HOMO and LUMO band gap energies, and the molecular electrostatic potential surface were also deducted for the stable structure of each compound. Also, we studied the prediction of absorption, distribution, metabolism and excretion (ADME) of the compounds.

A computational approach to identify novel plant metabolites against Aspergillus fumigatus

Aspergillus fumigatus, a common saprotrophic fungus is one of the most important causative agents of invasive aspergillosis. People with compromised immune systems or lung disorders are at a higher risk of acquiring Aspergillus-related health issues. The global number of invasive aspergillosis cases is expected to be over 300000 per year, with a 50 % death rate even when recognized and treated early. Current noninvasive therapies for fungal infections are azoles. As A. fumigatus resistance to azoles is rising, this study attempted to evaluate several plant metabolites as potential inhibitory agents of A. fumigatus by using in silico method. Five essential proteins including Chitinase, Glycosyl hydrolases, Glycosylphosphatidylinositol anchor, N-myristoyl transferase, and O-mannosyltransferases were selected as target proteins due to their involvement in morphogenetic processes, cell wall polysaccharides biosynthesis, filamentation, survival, organismal characteristics, proliferation, and cell wall integrity. Out of our 20 plant metabolites, four metabolites i.e., Chlorogenic acid, Protopine, Spirostanol, and Viniferin showed the best binding affinity with the key outer membrane protein of A. fumigatus during molecular docking analysis. Viniferin showed the highest binding affinity of about −262.07 and −247.63 with Chitinase and glycosyl hydrolases respectively. Molecular dynamic simulation was used to look further into the stability of the best two protein-ligand complexes. The average RMSD value of 2.4 A° for Chitinase-Viniferin and 2.2 A° for Glycosyl hydrolases-Viniferin complex demonstrated their excellent stability. ADME (absorption, distribution, metabolism, and excretion) analysis of these four plant metabolites showed that none of them had any side effects that might interfere with their drug-likeness efficiency, and no substantial toxic effects or allergenicity were also identified. Thus, all the predicted four plant metabolites can be used as a possible inhibitor of A. fumigatus. Furthermore, we strongly recommend more in vitro and in vivo trials to experimentally strengthen our encouraging outcomes.

Comparative docking studies of drugs and phytocompounds for emerging variants of SARS-CoV-2

The online version contains supplementary material available at 10.1007/s13205-022-03450-6.

Phytanic acid, an inconclusive phytol metabolite: A review

Phytanic acid (PA: 3,7,11,15-tetramethylhexadecanoic acid) is an important biometabolite of the chlorophyll-derived diterpenoid phytol. Its biological sources (occurrence) and ADME (absorption, distribution, metabolism, and elimination) profile are well-discussed in the literature. Cumulative literature suggests that PA has beneficial as well as harmful biological roles in humans and other animals. This study aimed to sketch a brief summary of PA’s beneficial and harmful pharmacological effects in test systems on the basis of existing literature reports. Literature findings propose that PA has anti-inflammatory and immunomodulatory, antidiabetic, anti-obesity, anticancer, and oocyte maturation effects. Although a high plasma PA-level mediated SLS remains controversial, it is evident to link it with Refsum’s disease and other peroxisomal enzyme deficiency diseases in humans, including RCDP and LD; ZHDA and Alzheimer’s disease; progressive ataxia and dysarthria; and an increased risk of some lymphomas such as LBL, FL, and NHL. PA exerts toxic effects on different kinds of cells, including neuronal, cardiac, and renal cells, through diverse pathways such as oxidative stress, mitochondrial disturbance, apoptosis, disruption of Na+/K+-ATPase activity, Ca2+ homeostasis, alteration of AChE and MAO activities, etc. PA is considered a cardiac biomarker in humans. In conclusion, PA may be one of the most important biometabolites in humans.

Curcumin-Based Heterocycles: Synthesis, Antimicrobial Genotoxicity and Molecular Docking

Curcumin is a natural compound with numerous biological activities and a precursor for many drugs. Development of a convenient one pot synthetic method for synthesizing curcumin-based diazepines and diazoles having antibacterial activities is focussed in this study. A one pot condensation process was developed for synthesizing a novel class of curcumin-based diazoles and diazepines by reacting curcumin with 2-diamino compounds and hydrazines in presence of sulfuric acid as catalyst. IR and 1H NMR were used to characterize the molecular composition of the synthesized curcumin derivatives. The synthesized derivatives were tested for their in vitro antibacterial efficacy against Gram-negative and Gram-positive bacteria. The MIC concentrations ranged from 1.56 to 200 μg/mL. Ampicillin exhibited synergistic effects with compounds C1, C3, C4 and C8. In the genotoxicity test, compound C3 was found to have no effect on the DNA molecules of E. coli strains, suggesting that it is not mutagenic and/or genotoxic. Compound C2 had the strongest interaction with the investigated protein receptor sites when blind molecular docking was conducted on all compounds. Since both H-donating and H-accepting sites of this molecule interact efficiently during the docking. In addition, absorption, distribution, metabolism and excretion (ADME) study showed that compound C2 do not contradict the Lipinski’s rule of drug likeness and showed a low level of passive human gastrointestinal absorption. The results indicated that C2 could be most promising among the studied compounds.

Visible light metallaphotoredox catalysis in the late-stage functionalization of pharmaceutically potent compounds

The late stage functionalization (LSF) is a distinctive approach for accelerating the discovery of structure–activity relationships (SARs) and optimising ADME (absorption, distribution, metabolism, and excretion) profiles.

Novel Set of Diarylmethanes to Target Colorectal Cancer: Synthesis, In Vitro and In Silico Studies.

Distinctive structural, chemical, and physical properties make the diarylmethane scaffold an essential constituent of many active biomolecules nowadays used in pharmaceutical, agrochemical, and material sciences. In this work, 33 novel diarylmethane molecules aiming to target colorectal cancer were designed. Two series of functionalized olefinic and aryloxy diarylmethanes were synthesized and chemically characterized. The synthetic strategy of olefinic diarylmethanes involved a McMurry cross-coupling reaction as key step and the synthesis of aryloxy diarylmethanes included an O-arylation step. A preliminarily screening in human colorectal cancer cells (HT-29 and HCT116) and murine primary fibroblasts (L929) allowed the selection, for more detailed analyses, of the three best candidates (10a, 10b and 12a) based on their high inhibition of cancer cell proliferation and non-toxic effects on murine fibroblasts (<100 µM). The anticancer potential of these diarylmethane compounds was then assessed using apoptotic (phospho-p38) and anti-apoptotic (phospho-ERK, phospho-Akt) cell survival signaling pathways, by analyzing the DNA fragmentation capacity, and through the caspase-3 and PARP cleavage pro-apoptotic markers. Compound 12a (2-(1-(4-methoxyphenyl)-2-(4-(trifluoromethyl)phenyl) vinyl) pyridine, Z isomer) was found to be the most active molecule. The binding mode to five biological targets (i.e., AKT, ERK-1 and ERK-2, PARP, and caspase-3) was explored using molecular modeling, and AKT was identified as the most interesting target. Finally, compounds 10a, 10b and 12a were predicted to have appropriate drug-likeness and good Absorption, Distribution, Metabolism and Excretion (ADME) profiles.

Molecular Docking and ADME Analysis of L-Phe -L-Tyr Dipeptide

Hypertension is a serious risk factor for various diseases. Therefore, lowering and preventing high blood pressure is a significant issue. Blockage of the renin-angiotensin-aldosterone system (RAAS), which controls blood pressure, is important to reduce blood pressure and consequently reduce symptoms of heart failure. This blockage can be carried out by angiotensin-converting enzyme (ACE) and angiotensin II receptor blockers (ARBs). The phenylalanyltyrosine (H-Phe-Tyr-OH, Phe-Tyr, L-Phe-L-Tyr, L-phenylalanyl-L-tyrosine) dipeptide examined in this study is an important structure that shows blood pressure lowering properties. For this reason, the potential of the peptide to be an ACE inhibitor or ARB was investigated. The molecular activity of the Phe-Tyr dipeptide was compared with antihypertensive drugs using theoretical calculations. Molecular docking method, one of these theoretical methods, has a considerable process in illuminating biochemical processes by investigating the interactions of drugs (ligands) with targeted receptors. In this theoretical study, molecular docking analyses of H-Phe-Tyr-OH dipeptide with ACE and Angiotensin II type 1 receptor (AT1R) were implemented. The interaction types and interaction regions of the peptide were also determined in comparison with drug molecules (Captopril, Enalapril, Telmisartan and Eprosartan) that are ACE inhibitors and ARBs. Lastly, ADME (absorption, distribution, metabolism, and excretion) analysis of the H-Phe-Tyr-OH dipeptide was also performed to estimate its drug potential. In this study, the pharmacokinetic properties of Phe-Tyr dipeptide and its mechanism of action with ACE and AT1R were investigated for the first time by molecular docking and ADME calculations.

Chemical Attachment of 5-Nitrosalicylaldimine Motif to Silatrane Resulting in an Organic-Inorganic Structure with High Medicinal Significance.

Two chemical motifs of interest for medicinal chemistry, silatrane as 1-(3-aminopropyl) silatrane (SIL M), and nitro group attached in position 5 to salicylaldehyde, are coupled in a new structure, 1-(3-{[(2-hydroxy-5-nitrophenyl)methylidene]amino}propyl)silatrane (SIL-BS), through an azomethine moiety, also known as a versatile pharmacophore. The high purity isolated compound was structurally characterized by an elemental, spectral, and single crystal X-ray diffraction analysis. Given the structural premises for being a biologically active compound, different specific techniques and protocols have been used to evaluate their in vitro hydrolytic stability in simulated physiological conditions, the cytotoxicity on two cancer cell lines (HepG2 and MCF7), and protein binding ability-with a major role in drug ADME (Absorption, Distribution, Metabolism and Excretion), in parallel with those of the SIL M. While the latter had a good biocompatibility, the nitro-silatrane derivative, SIL-BS, exhibited a higher cytotoxic activity on HepG2 and MCF7 cell lines, performance assigned, among others, to the known capacity of the nitro group to promote a specific cytotoxicity by a "activation by reduction" mechanism. Both compounds exhibited increased bio- and muco-adhesiveness, which can favor an optimized therapeutic effect by increased drug permeation and residence time in tumor location. Additional benefits of these compounds have been demonstrated by their antimicrobial activity on several fungi and bacteria species. Molecular docking computations on Human Serum Albumin (HSA) and MPRO COVID-19 protease demonstrated their potential in the development of new drugs for combined therapy.

Regioselective Synthesis and Molecular Docking Studies of 1,5-Disubstituted 1,2,3-Triazole Derivatives of Pyrimidine Nucleobases

1,2,3-triazoles are versatile building blocks with growing interest in medicinal chemistry. For this reason, organic chemistry focuses on the development of new synthetic pathways to obtain 1,2,3-triazole derivatives, especially with pyridine moieties. In this work, a novel series of 1,5-disubstituted-1,2,3-triazoles functionalized with pyrimidine nucleobases were prepared via 1,3-dipolar cycloaddition reaction in a regioselective manner for the first time. The N1-propargyl nucleobases, used as an alkyne intermediate, were obtained in high yields (87-92%) with a new two-step procedure that selectively led to the monoalkylated compounds. Then, FeCl3 was employed as an efficient Lewis acid catalyst for 1,3-dipolar cycloaddition between different aryl and benzyl azides and the N1-propargyl nucleobases previously synthesized. This new protocol allows the synthesis of a series of new 1,2,3-triazole derivatives with good to excellent yields (82-92%). The ADME (Absorption, Distribution, Metabolism, and Excretion) analysis showed good pharmacokinetic properties and no violations of Lipinsky's rules, suggesting an appropriate drug likeness for these new compounds. Molecular docking simulations, conducted on different targets, revealed that two of these new hybrids could be potential ligands for viral and bacterial protein receptors such as human norovirus capsid protein, SARS-CoV-2 NSP13 helicase, and metallo-β-lactamase.

Design Two Novel Tetrahydroquinoline Derivatives against Anticancer Target LSD1 with 3D-QSAR Model and Molecular Simulation

Lysine-specific demethylase 1 (LSD1) is a histone-modifying enzyme, which is a significant target for anticancer drug research. In this work, 40 reported tetrahydroquinoline-derivative inhibitors targeting LSD1 were studied to establish the three-dimensional quantitative structure-activity relationship (3D-QSAR). The established models CoMFA (Comparative Molecular Field Analysis (q2 = 0.778, Rpred2 = 0.709)) and CoMSIA (Comparative Molecular Similarity Index Analysis (q2 = 0.764, Rpred2 = 0.713)) yielded good statistical and predictive properties. Based on the corresponding contour maps, seven novel tetrahydroquinoline derivatives were designed. For more information, three of the compounds (D1, D4, and Z17) and the template molecule 18x were explored with molecular dynamics simulations, binding free energy calculations by MM/PBSA method as well as the ADME (absorption, distribution, metabolism, and excretion) prediction. The results suggested that D1, D4, and Z17 performed better than template molecule 18x due to the introduction of the amino and hydrophobic groups, especially for the D1 and D4, which will provide guidance for the design of LSD1 inhibitors.

Oral Pharmacokinetics of Hydroxycinnamic Acids: An Updated Review.

Hydroxycinnamic acids (HCAs) such as caffeic acid (CA), chlorogenic acid (CGA), coumaric acid (COA) isomers, ferulic acid (FA) and rosmarinic acid (RA) are natural phenolic acids with widespread distribution in vegetal foods and well-documented pharmacological activities. However, the low bioavailability of HCAs impairs their administration by the oral route. The present review addresses new findings and important factors/obstacles for their oral administration, which were unexplored in the reviews published a decade ago concerning the bioavailability of phenolic acids. Based on this, the article aims to perform an updated review of the water solubility and gastrointestinal stability of HCAs, as well as describe their oral absorption, distribution, metabolism and excretion (ADME) processes by in vitro, ex vivo, in situ and in vivo methods.

Pyrazole Derivative Containing Naphthalene Moiety: Cytotoxocity (Breast and Cervical Cancer), Antibacterial and Antifungal Studies Using Experimental and Theoretical Tools

In the present study, the title compound is named 4-((5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)(6-methoxynaphthalen-1-yl)methyl)-5-methyl-2-phenyl-1,2-dihydropyrazol-3-one was synthesized, and its antibacterial, antifungal, cytotoxic activity was studied by both experimental and in silico methods. The molecular structure was optimized using DFT/B3LYP method with cc-pVDZ as a besis set, and frontier molecular orbital (FMO) studies was used to explain the physiochemical properties of that molecule by the energy of interacting orbitals. NBO describes the intra delocalization of electrons in the molecule, which support the stability of that molecule. Noncovalent interaction (NCI) explains the nonbond interactions present in the molecule. Drug-likeness property of 405 C have been checked by absorption, distribution, metabolism and excretion (ADME) assay, result shown all the drug-likeness properties in red color region, so we have confirmed this molecule as a drug. 405 C undergoes antibiotic activity against P. aeruginosa organism, antifungal activity against B. cinerea and cytotoxicity activity against MCF-7 and HeLa cell when compared to standard drugs.

Exploration of Anti-HIV Phytocompounds against SARS-CoV-2 Main Protease: Structure-Based Screening, Molecular Simulation, ADME Analysis and Conceptual DFT Studies.

The ever-expanding pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has gained attention as COVID-19 and caused an emergency in public health to an unmatched level to date. However, the treatments used are the only options; currently, no effective and licensed medications are available to combat disease transmission, necessitating further research. In the present study, an in silico-based virtual screening of anti-HIV bioactive compounds from medicinal plants was carried out through molecular docking against the main protease (Mpro) (PDB: 6LU7) of SARS-CoV-2, which is a key enzyme responsible for virus replication. A total of 16 anti-HIV compounds were found to have a binding affinity greater than -8.9 kcal/mol out of 150 compounds screened. Pseudohypericin had a high affinity with the energy of -10.2 kcal/mol, demonstrating amino acid residual interactions with LEU141, GLU166, ARG188, and GLN192, followed by Hypericin (-10.1 kcal/mol). Moreover, the ADME (Absorption, Distribution, Metabolism and Excretion) analysis of Pseudohypericin and Hypericin recorded a low bioavailability (BA) score of 0.17 and violated Lipinski's rule of drug-likeness. The docking and molecular simulations indicated that the quinone compound, Pseudohypericin, could be tested in vitro and in vivo as potent molecules against COVID-19 disease prior to clinical trials.This was also supported by the theoretical and computational studies conducted. The global and local descriptors, which are the underpinnings of Conceptual Density FunctionalTheory (CDFT) have beenpredicted through successful model chemistry, hoping that they could be of help in the comprehension of the chemical reactivity properties of the molecular systems considered in this study.

In silico ADMET analysis of the A-, B- and D-modified androstane derivatives with potential anticancer effects

The major challenge in the fight against cancer is to design new drugs that will be more selective for cancer cells, with fewer side effects. Synthetic steroids such as cyproterone, fulvestrant, exemestane and abiraterone are approved powerful drugs for the treatment of hormone-dependent diseases such as breast and prostate cancers. Therefore, androstane derivatives in 17-substituted, 17a-homo lactone and 16,17-seco series, with potent anticancer activity, were selected for pharmacokinetic and druglike predictions from the absorption, distribution, metabolism and excretion (ADME) models. In silico determination of physico-chemical and ADMET properties was performed using SwissADME and ProTox-II web tools. The possibility of gastrointestinal absorption and brain penetration was analyzed using the BOILED-Egg model, while the in silico evaluation of the similarities between selected steroid derivatives and FDA-approved drugs was carried out using the SwissSimilarity tool. Of all tested, two compounds that showed good in silico ADMET results, in addition to promising cytotoxicity and molecular docking results, could potentially be evaluated in in vivo tests.

Design, synthesis, and biological evaluation of aminopyridine derivatives as novel tropomyosin receptor kinase inhibitors.

Tropomyosin receptor kinase (TRK) is a successful target for the treatment of various cancers caused by NTRK gene fusions. Herein, based on a rational drug design strategy, we designed and synthesized 35 aminopyrimidine derivatives that were shown to be TRKA inhibitors in the enzyme assay, among which compounds C3, C4, and C6 showed potent inhibitory activities against TRKA with IC50 values of 6.5, 5.0, and 7.0 nM, respectively. In vitro antiproliferative activity study showed that compound C3 significantly inhibited the proliferation of KM-12 cellsbut had weak inhibitory effect on MCF-7 cells and HUVEC cells. The preliminary druggability evaluation showed that compound C3 exhibited favorable liver microsomal and plasma stabilitiesand had weak or no inhibitory activity against cytochrome P450 isoforms at 10 µM. Compounds C3, C4, andC6 were also selected for ADME (absorption, distribution, metabolism, and elimination) properties prediction and molecular docking studies. Inhibition experiments showed that compound C3 was not selective for TRK subtypes. All results indicated that compound C3 was a useful candidate for the development of TRK inhibitors.

A Novel Inhibitor of FLT3 and Its Drug-Resistant Mutants with Superior Activity to Gilteritinib in Molm-13 Preclinical Acute Myeloid Leukemia Xenograft Model

Acute Myeloid Leukemia (AML) is a complex heterogenous disease characterized by the aberrant growth of undifferentiated myeloid progenitor cells typically driven by a combination of epigenetic and signaling mutations. In particular, fms-like tyrosine kinase 3 (Flt3) internal tandem duplication (FLT3-ITD) is associated with poor relapse-free and overall survival. Several FLT3 inhibitors have been developed such as the first generation multikinase inhibitor Midostaurin which is approved for newly diagnosed FLT3 mutant AML in combination with induction chemotherapy. Second generation inhibitors such as gilteritinib are more selective and potent and are also approved for relapsed/refractory FLT3 mutant AML. Although initial response has been positive with this class of agents, prolonged remission is rarely achieved, and diverse mechanisms of resistance often arise with FLT3 inhibitors representing an ongoing challenge. Common mechanisms of resistance to FLT3 inhibitors includes the acquisition of tyrosine kinase domain (TKD) secondary mutations such as the gatekeeper F691L TKD mutation, or the emergence of additional mutations in alternative signaling pathways such as RAS/MAPK. Thus, it is important to continue developing novel inhibitors capable of circumventing these resistance mechanisms. Herein we describe 2082-0047, a novel tyrosine kinase inhibitor with sub-nanomolar potency against FLT3 mutant AML, including TKD mutations. Compound 2082-0047 is a highly selective pan-FLT3 kinase inhibitor, as in both scanMAX and KdELECT KINOMEscan™ Profiling assays (Eurofins DiscoverX) it has shown 400-1000 fold selectivity. In our initial screening, 2082-0047 was only effective in FLT3-ITD mutant cells, however the KINOMEscan™ Profiling data described above demonstrates that 2082-0047 is potent against FLT3, FLT3 ITD, D835H, D835V, D835Y, D835V, K663Q, N841I, and R834Q FLT3 TKD mutations. We confirmed this data in a cellular assay using BaF3 cell lines expressing the TKD mutations D835Y, D835H or F691L alone or with Flt3-ITD. Next, we confirmed using immunoblot analysis of phosphorylated Flt3 that 2082-0047 is a potent inhibitor of FLT3-ITD signaling (superior to gilteritinib) in FLT3-ITD mutant AML cell lines. Using wildtype B6 mice, we conducted pharmacokinetic (PK) studies and found that 2082-0047 had 79 % oral bioavailability, achieved 1.2 μΜ Cmax after 4 hours, and had half-life of 4.7 hours. Next, our absorption, distribution, metabolism and excretion (ADME) studies showed lack of CYP inhibition of major human isoforms. Overall, our PK studies demonstrated overall favorable drug like properties enabling in vivo investigation of therapeutic activity. Therefore, we proceeded with using the MOLM-13 disseminated xenograft model in NCG recipient mice to determine the overall survival of 2082-0047 compared to gilteritinib. We enrolled mice 10 days post engraftment to receive daily oral vehicle, 3, 10, 20 or 30 mg/kg of 2082-0047 or 30 mg/kg of gilteritinib and found that 10 and 20 mg/kg of 2082-0047 were well tolerated and superior to gilteritinib at 30 mg/kg (Figure 1). In summary, we describe a novel and potent inhibitor of FLT3, including both internal tandem duplication and drug-resistant tyrosine kinase domain (TKD) mutants, with promising preclinical activity which is superior to the most potent FDA approved FLT3 inhibitor gilteritinib in an aggressive AML in vivo model. Our non-GLP in vivo safety studies confirmed a broad therapeutic window of 2082-0047. Ongoing Investigational New Drug (IND) enabling studies will include comparing the effect of 2082-0047 to gilteritinib in an immunocompetent syngeneic AML murine model harboring both a Flt3-ITD and F691 TKD gatekeeper mutation. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal