Semimechanistic Population PK/PD Modeling of Axatilimab in Healthy Participants and Patients With Solid Tumors or Chronic Graft-Versus-Host Disease.

Axatilimab, a high-affinity humanized immunoglobulin G4 monoclonal antibody against colony-stimulating factor 1 receptor (CSF-1R), is approved for the treatment of chronic graft-versus-host disease (cGVHD), and under investigation for idiopathic pulmonary fibrosis and solid tumors. The population pharmacokinetics (PK) and pharmacodynamics (PD) of axatilimab were characterized in healthy participants and patients with solid tumors or cGVHD using data from four clinical studies with 325 participants, including 278 patients with cGVHD. The model structure reflected the mechanism of action of axatilimab: blocking CSF-1R signaling with axatilimab reduces the circulating levels of cells in the mononuclear phagocytic cell lineage (including nonclassical monocytic cells (NCMCs) and Kupffer cells), resulting in increases in circulating enzymes owing to reduced clearance by Kupffer cells.

Pharmacokinetics of Zilurgisertib With and Without Food from Single and Multiple Ascending Dose Phase 1 Studies in Healthy Adults.

Background And Objectives: The oral, potent, and highly selective activin receptor-like kinase 2 (ALK2) inhibitor zilurgisertib (INCB000928) is in development as a treatment for fibrodysplasia ossificans progressiva (FOP), and for anemia due to myelofibrosis, myelodysplastic syndromes, and multiple myeloma. Saliva is an attractive alternative to blood for drug monitoring and pharmacokinetic analysis, as it is non-invasive to retrieve. This is beneficial for patients, such as those with FOP, for whom blood draws can be challenging due to soft tissue damage susceptibility that can cause progressive heterotopic ossification, and for whom tourniquet time and blood draws must be minimized.

Discovery of 5,7-Dihydro-6-pyrrolo[2,3-]pyrimidin-6-ones as Highly Selective CDK2 Inhibitors.

A series of exceptionally selective CDK2 inhibitors are described. Starting from an HTS hit, we successfully scaffold hopped to a 5,7-dihydro-6-pyrrolo[2,3-]pyrimidin-6-one core structure, which imparted a promising initial selectivity within the CDK family. Extensive further SAR identified additional factors that drove selectivity to above 200× for CDKs 1/4/6/7/9.

Discovery of Novel Pyrazolopyrimidines as Potent, Selective, and Orally Bioavailable Inhibitors of ALK2.

Activin receptor-like kinase 2 (ALK2) is a transmembrane kinase receptor that mediates the signaling of the members of the TGF-β superfamily. The aberrant activation of ALK2 has been linked to the rare genetic disorder fibrodysplasia ossificans progressiva (FOP) and diffuse intrinsic pontine glioma (DIPG) that are associated with severely reduced life expectancy in pediatric patients. ALK2 has also been shown to play an essential role in iron metabolism by regulating hepcidin levels and affecting anemia of chronic disease.

Discovery of a Partial Glucokinase Activator Clinical Candidate: Diethyl ((3-(3-((5-(Azetidine-1-carbonyl)pyrazin-2-yl)oxy)-5-isopropoxybenzamido)-1-pyrazol-1-yl)methyl)phosphonate (BMS-820132).

Glucokinase (GK) is a key regulator of glucose homeostasis, and its small-molecule activators represent a promising opportunity for the treatment of type 2 diabetes. Several GK activators have been advanced into clinical trials and have demonstrated promising efficacy; however, hypoglycemia represents a key risk for this mechanism. In an effort to mitigate this hypoglycemia risk while maintaining the efficacy of the GK mechanism, we have investigated a series of amino heteroaryl phosphonate benzamides as ''partial" GK activators.

Discovery of an Oxycyclohexyl Acid Lysophosphatidic Acid Receptor 1 (LPA) Antagonist BMS-986278 for the Treatment of Pulmonary Fibrotic Diseases.

The oxycyclohexyl acid BMS-986278 () is a potent lysophosphatidic acid receptor 1 (LPA) antagonist, with a human LPA of 6.9 nM. The structure-activity relationship (SAR) studies starting from the LPA antagonist clinical compound BMS-986020 (), which culminated in the discovery of , are discussed.

Itacitinib (INCB039110), a JAK1 Inhibitor, Reduces Cytokines Associated with Cytokine Release Syndrome Induced by CAR T-cell Therapy.

Purpose: T cells engineered to express a chimeric antigen receptor (CAR) are a promising cancer immunotherapy. Such targeted therapies have shown long-term relapse-free survival in patients with B-cell leukemia and lymphoma. However, cytokine release syndrome (CRS) represents a serious, potentially life-threatening side effect often associated with CAR T-cell therapy.

Discovery of Potent Protease-Activated Receptor 4 Antagonists with in Vivo Antithrombotic Efficacy.

In an effort to identify novel antithrombotics, we have investigated protease-activated receptor 4 (PAR4) antagonism by developing and evaluating a tool compound, , in a monkey thrombosis model. Beginning with a high-throughput screening hit, we identified an imidazothiadiazole-based PAR4 antagonist chemotype. Detailed structure-activity relationship studies enabled optimization to a potent, selective, and orally bioavailable PAR4 antagonist, .

Label-Free Bottom-Up Proteomic Workflow for Simultaneously Assessing the Target Specificity of Covalent Drug Candidates and Their Off-Target Reactivity to Selected Proteins.

Although designed covalent inhibitors as drug candidates offer several unique advantages over conventional reversible inhibitors, including high potency and the potential for less frequent dosing, there is a general tendency to avoid the covalent mode of action in drug discovery programs due to concerns regarding immune-mediated toxicity that can arise from indiscriminate reactivity with off-target proteins. Therefore, the ability to assess off-target reactivity relative to target specificity is desirable for optimizing covalent drug candidates in the early discovery stage. One concern with current surrogate nucleophile trapping approaches is that they employ a simplistic model nucleophile such as glutathione, which may not reliably reflect the covalent interactions with cellular or extracellular proteins.

Effects of dietary yeast nucleotides on growth, non-specific immunity, intestine growth and intestinal microbiota of juvenile hybrid tilapia ♀ × ♂.

This study investigated the effect of dietary supplementation of yeast nucleotides on the growth, non-specific immunity, intestine growth and intestinal microbiota of juvenile hybrid tilapia. Tilapia (initial average weight of 8.02 g) was fed test diets supplemented with a yeast-originated nucleotide mixture (0, 0.

Conjugated linoleic acid alters growth performance, tissue lipid deposition, and fatty acid composition of darkbarbel catfish (Pelteobagrus vachelli).

Fatty liver syndrome is a prevalent problem of farmed fish. Conjugated linoleic acid (CLA) has received increased attention recently as a fat-reducing fatty acid to control fat deposition in mammals. Therefore, the aim of the present study was to determine whether dietary CLA can reduce tissue lipid content of darkbarbel catfish (Pelteobagrus vachelli) and whether decreased lipid content is partially due to alterations in lipid metabolism enzyme activities and fatty acid profiles.

Identification of human liver microsomal proteins adducted by a reactive metabolite using shotgun proteomics.

Covalent modification of cellular proteins by chemically reactive compounds/metabolites has the potential to disrupt biological function and elicit serious adverse drug reactions. Information on the nature and binding patterns of protein targets are critical toward understanding the mechanism of drug induced toxicity. Protein covalent binding studies established in liver microsomes can quantitively estimate the extent of protein modification, but they provide little information on the nature of the modified proteins.

Effects of dietary microencapsulated sodium butyrate on growth, intestinal mucosal morphology, immune response and adhesive bacteria in juvenile common carp (Cyprinus carpio) pre-fed with or without oxidised oil.

The aim of the present study was to investigate the effects of different dietary sustained-release microencapsulated sodium butyrate (MSB) products (0 (non-supplement), 1·5 and 3·0 h) for a control or oxidised soyabean oil (SBO) diet on fish production, intestinal mucosal condition, immunity and intestinal bacteria in juvenile common carp (Cyprinus carpio). Dietary MSB increased weight gain and reduced the feed conversion ratio within the control and oxidised SBO groups. Gut mucosa was damaged in the oxidised SBO group fed without MSB, in contrast to a normal appearance found in fish fed the MSB1·5 and MSB3·0 diets in the oxidised SBO group.

Bioactivation of 2-(alkylthio)-1,3,4-thiadiazoles and 2-(alkylthio)-1,3-benzothiazoles.

Certain functional groups/structural motifs are known to generate chemically reactive metabolites that can covalently modify essential cellular macromolecules and, therefore, have the potential to disrupt biological function and elicit idiosyncratic adverse drug reactions. In this report, we describe the bioactivation of 5-substituted 2-(alkylthio)-1,3,4-thiadiazoles and 2-(alkylthio)-1,3-benzothiazoles, which can be added to the growing list of structural alerts. When 5-substituted 2-(methylthio)-1,3,4-thiadiazoles and 2-(methylthio)-1,3-benzothiazole were incubated with pooled human liver microsomes in the presence of NADPH and GSH, unusual GSH adducts were formed.

Quantitative estimation of circulating metabolites without synthetic standards by ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry in combination with UV correction.

An early assessment of metabolite exposure in preclinical species can provide quantitative estimation on possible active or toxic metabolites. Frequently, synthetic metabolite standards are not available at the preclinical stage, precluding the quantitation of metabolites by means of calibration curves and quality control (QC) samples. We present here an approach to determine the extent of circulating metabolites using 'metabolite standards' generated by in vitro incubations in combination with the correction for mass spectrometry response based on UV response.

An algorithm for thorough background subtraction from high-resolution LC/MS data: application for detection of glutathione-trapped reactive metabolites.

A control sample background-subtraction algorithm was developed for thorough subtraction of background and matrix-related signals in high-resolution, accurate mass liquid chromatography/mass spectrometry (LC/MS) data to reveal ions of interest in an analyte sample. This algorithm checked all ions in the control scans within a specified time window around the analyte scan for potential subtraction of ions found in that analyte scan. Applying this method, chromatographic fluctuations between runs were dealt with and background and matrix-related signals in the sample could be thoroughly subtracted.

P450 phenotyping of the metabolism of selegiline to desmethylselegiline and methamphetamine.

Although there is evidence in the literature of the participation of CYP2B6 in the metabolism of selegiline, it is not clear which other CYP isoforms contribute to its metabolism. The aim of this study was to investigate the P450 isozymes (CYPs) involved in the metabolism of selegiline to desmethylselegiline (DMS) and methamphetamine (MA) using four assays: incubation of selegiline with cDNA expressed CYPs, inhibition of DMS and MA formations in human liver microsomes by CYP-selective chemical inhibitors or CYP-specific antibodies, and correlation analysis. Correlation analysis, performed in a bank of 15 individual human liver microsomes, yielded correlation coefficients for DMS and MA formation of 0.

Coupling on-chip solid-phase extraction to electrospray mass spectrometry through an integrated electrospray tip.

We report the integration of solid-phase extraction (SPE) with mass spectrometry (MS) through an on-chip electrospray tip for sample precleaning and preconcentration. An in situ polymerized alkylacrylate-based monolithic column was used as the stationary phase for the on-chip SPE. Each microchip consists of two sets of microchannels and their respective integrated electrospray tips, with a common gold electrode.

A polymeric microchip with integrated tips and in situ polymerized monolith for electrospray mass spectrometry.

We describe the integration of a cyclo-olefin polymer based microchip with a sheathless capillary tip for electrospray ionization-mass spectrometry (ESI-MS). The microchip was fabricated by hot embossing and thermal bonding. Its design includes a side channel for adjusting the composition of the electrospray solution so that analytes in 100% water can be analyzed.

Isoelectric focusing in cyclic olefin copolymer microfluidic channels coated by polyacrylamide using a UV photografting method.

As an alternative material to glass or silicon, microfluidic devices made from a cyclic olefin copolymer (COC) were fabricated. This material is of interest because of the relative ease of fabrication, low costs, and solvent resistance. However, as a result of the strong hydrophobic interactions normally present, COC surfaces are not suitable for protein separations.

Quantitative mass spectrometric determination of methylphenidate concentration in urine using an electrospray ionization source integrated with a polymer microchip.

We have demonstrated the use of a simple microfabricated electrospray ionization source for coupling microfluidic chips to mass spectrometry (MS). A polymer-based microchip, coupled to a triple quadrupole mass spectrometer, has been employed for direct infusion quantitative bioanalysis of methylphenidate (Ritalin) extracted from human urine samples. The approach used a microfabricated polymer electrospray emitter to couple a microfluidic channel to a stable electrospray ionization source.