Favorable Pharmacokinetic Profile Research Articles

New Quinazolinone‐Tethered 1,2,3‐Triazoles aSs Potent Antimicrobial Agents: Design, Synthesis, Biological Evaluation and in silico Docking Study

AbstractNovel 1,2,3‐triazole acetamide linked quinazolinone derivatives were synthesized via click reaction, by reacting of 3‐methyl‐2‐(prop‐2‐yn‐1‐ylthio)quinazolin‐4(3H)‐one with various aryl azides as prominent fungal pathogen Candida albicans interactions. The prepared triazole compounds were characterized using mass spectrometry, 1H NMR, 13C NMR, and IR spectroscopic techniques. Compounds were screened for their in vitro antibacterial and antifungal activity against a variety of microorganisms namely, Bacillus subtilis, Enterococcus faecalis, Klebsiella pneumonia, Escherichia coli, Aspergillus fumigatus, Candida albicans, and Aspergillus clavatus. Quinazolinone linked p‐hydroxyphenyl, o, p‐dihydroxyphenyl and o‐dimethylamino phenyl triazoles showed a remarkable antibacterial activity against E. faecalis with MIC values of 3.20±0.01, 4.01±0.04, and 4.10±0.01 μg mL−1, and screened compounds p‐nitrophenyl substituted triazole, and p‐methylphenyl substituted triazole displayed a significant antifungal activity against C. albicans with MICs of 3.16±0.01, 4.06±0.03 μg mL−1, compared to itraconazole (MIC=3.32±0.02 μg mL−1). For further exploration of the anti‐fungal mechanism of action, molecular docking was carried out for these compounds in C. albicans active site as one of the important antifungal inhibitors (PDB: 1A19). Furthermore, the ADMET profile was evaluated for all the final triazole compounds in contrast to reference drugs moxifloxacin and itraconazole. In conclusion, we discovered a novel quinazolinone linked 1,2,3‐triazoles with promising antimicrobial activity and a favorable pharmacokinetic profile.

Novel Relaxin Receptor RXFP1 Agonist AZD3427 in the Treatment of Heart Failure: A Phase 1a/b, First-in-Human, Randomized, Single-Blind, Placebo-Controlled Study.

Heart failure mortality remains high despite recent progress in pharmacological treatment. AZD3427 is a selective long-acting analog of relaxin, a vasodilatory hormone with antifibrotic effects. We assessed the safety, pharmacokinetics, and pharmacodynamics of AZD3427 in healthy volunteers and patients with heart failure on standard-of-care therapy. In this first-in-human, phase 1a/b, randomized, single-blind, placebo-controlled study, healthy volunteers were randomized 6:2 to receive a single dose of AZD3427 or placebo by subcutaneous injection in 5 mixed-ethnicity cohorts (5, 10, 30, 90, or 270 mg) and 1 Japanese-descent cohort (270 mg), or by intravenous injection in 1 cohort (15 mg). After confirming safety and tolerability in healthy volunteers, 3 cohorts of patients with heart failure and left ventricular ejection fraction ≤40% and 3 cohorts with ejection fraction ≥41% were randomized 6:2 to receive 5 weekly doses of AZD3427 (5, 15, or 45 mg) or placebo by subcutaneous injection. In total, 56 healthy volunteers and 48 patients with heart failure were randomized. AZD3427 was well tolerated at all doses. After subcutaneous administration, AZD3427 was absorbed slowly, and exposure was approximately linear across the dose range. In patients with heart failure, AZD3427 terminal half-life was 13 to 14 days and there were numerical increases in stroke volume and estimated glomerular filtration rate. No treatment-emergent antidrug antibodies were detected. AZD3427 had favorable safety and pharmacokinetic profiles. Hemodynamic changes in patients with heart failure were consistent with the anticipated effects of a relaxin analog. These findings support further development of AZD3427 as a novel long-term treatment for patients with heart failure. URL: https://www.clinicaltrials.gov; Unique Identifier: NCT04630067.

Discovery of a Potent and Orally Bioavailable Xanthine Oxidase/Urate Transporter 1 Dual Inhibitor as a Potential Treatment for Hyperuricemia and Gout.

The main uric acid-lowering agents in clinical use for hyperuricemia and gout are xanthine oxidase (XO) inhibitors or urate transporter 1 (URAT1) inhibitors. While these therapies can partially control the disease, they have various limitations. The development of XO/URAT1 dual inhibitors offers the potential to enhance therapeutic potency and reduce toxicity compared with single-target inhibitors. Through scaffold hopping from the XO inhibitor febuxostat (2) and the URAT1 inhibitor probenecid (3), followed by structure-activity relationship (SAR) studies, we identified compound 27 as a potent dual inhibitor of XO and URAT1. Compound 27 demonstrated significant dual inhibition in vitro (XO IC50 = 35 nM; URAT1 IC50 = 31 nM) and exhibited favorable pharmacology and pharmacokinetic (PK) profiles in multiple species including monkeys. Furthermore, toxicity studies in rats and monkeys revealed general safety profiles, supporting that compound 27 emerges as a promising novel drug candidate with potent XO/URAT1 dual inhibition for the treatment of gout.

Synthesis, molecular docking, drug‐likeness analysis, and ADMET prediction of nickel and zinc tetraphenyl‐porphyrin complexes as possible antioxidant agents

AbstractNickel tetraphenyl‐porphyrin (NiTPPH₂) and zinc tetra(4‐methophenyl)‐porphyrin (ZnTPPH₂(p‐methyl)) were successfully synthesized and characterized using 1H NMR spectroscopy. Their antioxidant activities and interactions with the superoxide anion radical () were evaluated using cyclic voltammetry. Remarkably, NiTPPH₂ displayed superior antioxidant activity with an IC50 value of 54.57 μg mL−1, significantly outperforming α‐tocopherol (IC50 = 353.27 μg mL−1), indicating its potential as a potent antioxidant. Binding free energy calculations demonstrated that electrostatic interactions predominantly govern the binding, with values of −23.47 kJ mol−1 for NiTPPH₂ and −22.50 kJ mol−1 for ZnTPPH₂(p‐methyl). These values suggest robust binding affinities with . Quantum chemical parameters, obtained through density functional theory (DFT), showed a strong correlation with experimental results, validating the computational approach. Additionally, ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) and drug‐likeness assessments, alongside molecular docking studies, highlighted favorable pharmacokinetic profiles and binding affinities. These findings underscore the potential of NiTPPH₂ and ZnTPPH₂(p‐methyl) as promising candidates for antioxidant therapy, exhibiting drug‐like properties and favorable pharmacokinetics. This research advances the understanding of these porphyrin derivatives and their application in the development of novel antioxidant therapeutics.

Prediction of Protein-Drug Interactions, Pharmacophore Modeling, and Toxicokinetics of Novel Leads for Type 2 Diabetes Treatment.

Small heterocyclic compounds have been crucial in pioneering advances in type 2 diabetes treatment. There has been a dramatic increase in the pharmacological development of novel heterocyclic derivatives aimed at stimulating the activation of Glucokinase (GK). A pharmaceutical intervention for diabetes is increasingly targeting GK as a legitimate target. Diabetes type 2 compromises Glucokinase's function, an enzyme vital for maintaining the balance of blood glucose levels. Medicinal substances strategically positioned to improve type 2 diabetes management are used to stimulate the GK enzyme using heterocyclic derivatives. The research endeavor aimed to craft novel compounds, drawing inspiration from the inherent coumarin nucleus found in nature. The goal was to evoke the activity of the glucokinase enzyme, offering a tailored approach to mitigate the undesired side effects typically associated with conventional therapies employed in the treatment of type 2 diabetes. Coumarin, sourced from nature's embrace, unfolds as a potent and naturally derived ally in the quest for innovative antidiabetic interventions. Coumarin was extracted from a variety of botanical origins, including Artemisia keiskeana, Mallotus resinosus, Jatropha integerrima, Ferula tingitana, Zanthoxylum schinifolium, Phebalium clavatum, and Mammea siamensis. This inclusive evaluation was conducted on Muybridge's digital database containing 53,000 hit compounds. The presence of the coumarin nucleus was found in 100 compounds, that were selected from this extensive repository. Utilizing Auto Dock Vina 1.5.6 and ChemBioDraw Ultra, structures generated through this process underwent docking analysis. Furthermore, these compounds were accurately predicted online log P using the Swiss ADME algorithm. A predictive analysis was conducted using PKCSM software on the primary compounds to assess potential toxicity. Using Auto Dock Vina 1.5.6, 100 coumarin derivatives were assessed for docking. Glucokinase (GK) binding was significantly enhanced by most of these compounds. Based on superior binding characteristics compared with Dorzagliatin (standard GKA) and MRK (co-crystallized ligand), the top eight molecules were identified. After further evaluation through ADMET analysis of these eight promising candidates, it was confirmed that they met the Lipinski rule of five and their pharmacokinetic profile was enhanced. The highest binding affinity was demonstrated by APV16 at -10.6 kcal/mol. A comparison between the APV16, Dorzagliatin and MRK in terms of toxicity predictions using PKCSM indicated that the former exhibited less skin sensitization, AMES toxicity, and hepatotoxicity. Glucokinase is most potently activated by 100 of the compound leads in the database of 53,000 compounds that contain the coumarin nucleus. APV12, with its high binding affinity, favorable ADMET (adjusted drug metabolic equivalents), minimal toxicity, and favorable pharmacokinetic profile warrants consideration for progress to in vitro testing. Nevertheless, to uncover potential therapeutic implications, particularly in the context of type 2 diabetes, thorough investigations and in-vivo evaluations are necessary for benchmarking before therapeutic use, especially experiments involving the STZ diabetic rat model.

Safety, Tolerability, and Pharmacokinetics of Nebulized GB05-Human IFNα1b Inhalation Solution: A Randomized, Placebo-Controlled, Dose-Escalation PhaseI Study in Healthy Chinese Adult Volunteers.

Human respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infection, especially in children and older people. However, no effective treatment is currently available. TypeI interferons (IFNs) are a group of cytokines that help regulate the activity of the immune system. GB05, human IFNα1b inhalation solution, was developed under US Food and Drug Administration (FDA) standard guidelines to combat RSV infection. This randomized, double-blind, placebo-controlled, dose-escalation phaseI trial evaluated the safety, tolerability, and pharmacokinetics of nebulized GB05. A total of 35 eligible healthy Chinese adult volunteers were enrolled in this study. In the single ascending dose (SAD) study, volunteers were randomized into 0.2, 0.6, 1.2, and 1.8million IU of GB05 or placebo. In the multiple ascending dose (MAD) study, volunteers received 1.2 or 1.8million IU of GB05 or placebo for four consecutive days. Safety, tolerability, immunogenicity, and plasma pharmacokinetics were assessed for all groups. All adverse events were mild or moderate and resolved spontaneously. The most common adverse event was decreased white blood cell count (8.6% in SAD and 10% in MAD). No serious adverse events, deaths, or adverse events that reached the termination criteria occurred during the study. In SAD, the maximum concentration and area under the curve increased across the dose range of 1.2-1.8million IU in a non-linear relationship. The maximum plasma concentration after GB05 nebulization (1.06IU/ml in the 1.8million IU group) reflected a low concentration in the blood, suggesting a better lung uptake of GB05 and reduced incidence or risks of adverse events. In MAD, a steady state was reached after continuous administrations of twice daily for 3days. Overall, nebulized GB05 exhibited satisfactory safety, tolerability, and favorable pharmacokinetic (PK) profiles in healthy adult volunteers, supporting further clinical investigation in patients infected with respiratory syncytial virus. ClinicalTrials.gov Identifier NCT06277167.

Identification and Characterization of a Blood-Brain Barrier Penetrant Inositol Hexakisphosphate Kinase (IP6K) Inhibitor.

Inositol hexakisphosphate kinases (IP6Ks) have been studied for their role in glucose homeostasis, metabolic disease, fatty liver disease, chronic kidney disease, neurological development, and psychiatric disease. IP6Ks phosphorylate inositol hexakisphosphate (IP6) to the pyrophosphate, 5-diphosphoinositol-1,2,3,4,6-pentakisphosphate (5-IP7). Most of the currently known potent IP6K inhibitors contain a critical carboxylic acid which limits blood-brain barrier (BBB) penetration. In this work, the synthesis and testing of a variety of carboxylic acid isosteres resulted in several new compounds with improved BBB penetration. The most promising compound has an IP6K1 IC50 of 16 nM with an improved brain/plasma ratio and a favorable pharmacokinetic profile. This series of brain penetrant compounds may be used to investigate the role of IP6Ks in CNS disorders.

Exploring highly selective polymethoxy fenamate isosteres as novel anti-prostate cancer agents: Synthesis, biological activity, molecular docking, molecular dynamics, and ADME studies

In this study, we synthesized and characterized sixteen new polymethoxy-substituted hydrazone derivatives. These compounds were evaluated for their in vitro cytotoxic activity against human prostate cancer (PC3) and human umbilical vein endothelial (HUVEC) cell lines. Compounds 5, 6, 7, and 11 exhibited significant cytotoxic effects with high selectivity index. Molecular docking studies and MM-GBSA binding free energy calculations were performed against tubulin protein. Compound 7 emerged as a particularly promising candidate, displaying an IC50 value of 1.49 µM against PC3 cells and a selectivity index of 264. Compound 7 achieved impressive docking score -13.655 kcal/mol against tubulin and formed stable hydrogen bonds and π-π stacking interactions with key residues in this protein. MD simulations confirmed the stability of the 7-tubulin complex. ADME analysis indicated that compound 7 has favorable absorption, solubility, and permeability properties, with minimal rule violations. The SAR analysis highlighted the significance of specific functional groups in enhancing the compound's cytotoxic and binding properties. Overall, compound 7 is identified as a leading candidate due to its exceptional cytotoxicity, high selectivity index, strong binding affinities, and favorable pharmacokinetic profile, making it a top candidate for further investigation and development as a novel anticancer agent.

Comprehensive analysis of Indacaterol and Theophylline molecules: insights from DFT, FTIR, Raman, UV, molecular docking, and ADMET studies

In this study, the structural, vibrational, and biological properties of Indacaterol and Theophylline were thoroughly investigated using quantum chemical and spectroscopic methods, and then compared with experimental FTIR, Raman, and UV–Vis data. The analysis revealed that electronegative oxygen and nitrogen atoms in both molecules facilitate charge transfers, resulting in the shortening of C–C bonds. The HOMO–LUMO energy gaps were found to be 4.298 eV for Indacaterol and 5.170 eV for Theophylline, indicating that Indacaterol is more bioactive. The electrophilic index values suggest that Indacaterol is more electrophilic, potentially offering a higher affinity for protein binding. Molecular electrostatic potential surface maps indicated that electrophilic regions are concentrated near the oxygen and nitrogen atoms, which was corroborated by molecular docking analysis. Binding affinities of Indacaterol and Theophylline to COVID-19 main protease proteins were calculated, showing higher affinities for Indacaterol. Drug likeness, physicochemical, and ADMET results suggest that both molecules have favorable pharmacokinetic profiles and comply with Lipinski’s Rule of Five, indicating effective absorption and distribution. Overall, the study suggests that Indacaterol and Theophylline could function as inhibitors against SARS-CoV-2 and COVID-19 proteins, with Indacaterol potentially being more effective.

Computational design of novel therapeutics targeting Schistosomiasis, a neglected tropical disease

Schistosomiasis, caused by flatworm parasites, is a widespread disease resulting in chronic illness and fatalities globally. Given the risk of drug resistance and limited treatment options, finding new therapeutic options are crucial for managing and controlling this neglected tropical disease. In this research, various in-silico methods including Density-Functional-Theory (DFT) computations, Molecular-docking, molecular dynamics simulations and Pharmacokinetic evaluation were employed to identify ten potential inhibitors of Schistosoma mansoni HDAC8 (SmHDAC8). The modeled activities (pIC50) of these newly designed compounds (ranging between 7.110 and 6.959) surpassed that of the hit compound 19 (pIC50 = 6.445) and the standard reference control, Praziquantel (pIC50 = 5.989). Moreover, the MolDock scores (ranging between −188.964 and −158.351 kcal/mol) for these proposed compounds in the SmHDAC8 binding cavity outperformed the hit template 19 (MolDock score: −122.516 kcal/mol) and the Praziquantel (−110.245 kcal/mol). Furthermore, the conformational stability of the top three designed compounds (19a, 19i, and 19j) in the SmHDAC8 binding cavity was examined through a 100 ns of Molecular Dynamics simulation. Additionally, the drug-likeness and ADMET predictions of these compounds indicated favorable oral bioavailability and pharmacokinetic profiles. This study offers a reliable in-silico approach for identifying potential agents against Schistosomiasis.

Hybrid Virtual Screening Approach to Predict Novel Natural Compounds against HIV-1 CCR5.

Human immunodeficiency virus (HIV) infection continues to pose a major global health challenge. HIV entry into host cells via membrane fusion mediated by the viral envelope glycoprotein gp120/gp41 is a key step in the HIV life cycle. CCR5, expressed on CD4+ T cells and macrophages, acts as a coreceptor facilitating HIV-1 entry. The CCR5 antagonist maraviroc is used to treat HIV infection. However, it can cause adverse effects and has limitations such as only inhibiting CCR5-tropic viruses. There remains a need to develop alternative CCR5 inhibitors with improved safety profiles. Natural products may offer advantages over synthetic inhibitors including higher bioavailability, binding affinity, effectiveness, lower toxicity, and molecular diversity. However, screening the vast chemical space of natural compounds to identify novel CCR5 inhibitors presents challenges. This study aimed to address this gap through a hybrid ligand-based pharmacophore modeling and molecular docking approach to virtually screen large natural product databases. A reliable pharmacophore model was developed based on 311 known CCR5 antagonists and validated against an external data set. Five natural product databases containing over 306,000 compounds were filtered based on drug-likeness rules. The validated pharmacophore model screened the databases to identify 611 hits. Key residues of the CCR5 receptor crystal structure were identified for docking. The top hits were docked, and interactions were analyzed. Molecular dynamics simulations were conducted to examine complex stability. Computational prediction evaluated pharmacokinetic properties. Three compounds exhibited similar interactions and binding energies to maraviroc. MD simulations demonstrated complex stability comparable to maraviroc. One compound showed optimal predicted absorption, minimal metabolism, and a lower likelihood of interactions than maraviroc. This computational screening workflow identified three natural compounds with promising CCR5 inhibition and favorable pharmacokinetic profiles. One compound emerged as a lead based on bioavailability potential and minimal interaction risk. These findings present opportunities for developing alternative CCR5 antagonists and warrant further experimental investigation. Overall, the hybrid virtual screening approach proved effective for mining large natural product spaces to discover novel molecular entities with drug-like properties.

Remimazolam for sedation in gastrointestinal endoscopy: A comprehensive review.

Worldwide, a majority of routine endoscopic procedures are performed under some form of sedation to maximize patient comfort. Propofol, benzodiazepines and opioids continue to be widely used. However, in recent years, Remimazolam is gaining immense popularity for procedural sedation in gastrointestinal (GI) endoscopy. It is an ultra-short-acting benzodiazepine sedative which was approved by the Food and Drug Administration in July 2020 for use in procedural sedation. Remimazolam has shown a favorable pharmacokinetic and pharmacodynamic profile in terms of its non-specific metabolism by tissue esterase, volume of distribution, total body clearance, and negligible drug-drug interactions. It also has satisfactory efficacy and has achieved high rates of successful sedation in GI endoscopy. Furthermore, studies have demonstrated that the efficacy of Remimazolam is non-inferior to Propofol, which is currently a gold standard for procedural sedation in most parts of the world. However, the use of Propofol is associated with hemodynamic instability and respiratory depression. In contrast, Remimazolam has lower incidence of these adverse effects intra-procedurally and hence, may provide a safer alternative to Propofol in procedural sedation. In this comprehensive narrative review, highlight the pharmacologic characteristics, efficacy, and safety of Remimazolam for procedural sedation. We also discuss the potential of Remimazolam as a suitable alternative and how it can shape the future of procedural sedation in gastroenterology.

LC-MS and GC-MS Analyses on Green Algae Penicillus capitatus: Cytotoxic, Antimicrobial and Anticholinesterase Activity Screening Enhanced by Molecular Docking & Dynamics and ADME Studies.

In this comprehensive screening study, the chemical composition, and cytotoxic, antimicrobial, and anticholinergic activities of the green algae Penicillus capitatus, collected from Antalya-Türkiye, were determined as in vitro and in silico. GC-MS analysis of the hexane extract revealed a high content of fatty acids, with hexadecanoic acid constituting half of the total fatty acid content. LC-HRMS analysis of the DCM:MeOH extract identified ascorbic acid as the most abundant compound, followed by (-)-epigallocatechin and salicylic acid. The DCM:MeOH extract exhibited potent cytotoxicity against MDA-MB-231 and MCF7 breast cancer cell lines, outperforming doxorubicin with lower IC50 values and a higher selectivity index. Additionally, the extract demonstrated significant antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans, along with selective inhibition of acetylcholinesterase (hAChE) over butyrylcholinesterase (hBChE). Molecular docking and dynamics studies revealed that apigenin-7-O-glucoside and epigallocatechin form stable interactions with estrogen receptor alpha (ERα) and hAChE, suggesting their potential as inhibitors. In silico ADME studies indicated favorable pharmacokinetic profiles for the detected compounds, supporting their potential as drug candidates. The promising cytotoxic activity of the P. capitatus extracts, coupled with significant antimicrobial properties and selective hAChE inhibition, highlights their therapeutic potential for breast cancer treatment, infection management, and neurodegenerative disease intervention.

Clinical experience of outpatient treatment of bacterial skin infections in children

Data regarding the role of cutaneous microbiome in physiological and pathological conditions, pharmacological properties of fusidic acid and its clinical use for the treatment of skin infections are presented in the article. Incidence of skin infections in children treated in children’s city polyclinic No. 1 of Izhevsk city through 2019–2022 are analyzed. Outcomes of the treatment of these patients with topical fusidic acid preparations are presented. Due to high activity against typical cutaneous bacterial pathogens including MRSA strains of Staphylococcus aureus, favorable safety profile and pharmacokinetic profile when topically applied along with low resistance of the key pathogens fusidic acid preparations are the first line treatment of primary and secondary pyodermas.

Safety, Pharmacokinetics, and Pharmacodynamics of the New Aldose Reductase Inhibitor Govorestat (AT-007) After a Single and Multiple Doses in Participants in a Phase 1/2 Study.

In classic galactosemia (CG) patients, aldose reductase (AR) converts galactose to galactitol. In a phase 1/2, placebo-controlled study (NCT04117711), safety, pharmacokinetics (PK), and pharmacodynamics (PD) of govorestat were evaluated after single and multiple ascending doses (0.5-40 mg/kg) in healthy adults (n = 81) and CG patients (n = 14). Levels of govorestat in plasma and cerebrospinal fluid (CSF) and blood levels of galactitol, galactose, and galactose-1-phosphate (Gal-1p) were measured for population PK and PK/PD analyses. Govorestat was well tolerated. Adverse event frequency was comparable between placebo and govorestat. Govorestat PK displayed a 2-compartment model with sequential zero- and first-order absorption, and no effect of demographic factors. Multiple-dose PK of govorestat was linear in the 0.5-40 mg/kg range, and CSF levels increased dose dependently. Elimination half-life was ∼10 h. PK/PD modeling supported once-daily dosing. Change from baseline in galactitol was -15% ± 9% with placebo and -19% ± 10%, -46% ± 4%, and -51% ± 5% with govorestat 5, 20, and 40 mg/kg, respectively, thus was similar for 20 and 40 mg/kg. Govorestat did not affect galactose or Gal-1p levels. In conclusion, govorestat displayed a favorable safety, PK, and PD profile in humans, and reduced galactitol levels in the same magnitude (∼50%) as in a rat model of CG that demonstrated an efficacy benefit on neurological, behavioral, and ocular outcomes.

Anti-quorum sensing activity of α-amidoamides against Agrobacterium tumefaciensNT1: Insights from molecular docking and dynamic investigations to synergistic approach of metronidazole release from gel formulations

A unique approach is imperative for the development of drugs aimed at inhibiting various stages of infection, rather than solely focusing on bacterial viability. Among the array of unconventional targets explored for formulating novel antimicrobial medications, blocking the quorum-sensing (QS) system emerges as a highly effective and promising strategy against a variety of pathogenic microbes. In this investigation, we have successfully assessed nine α-aminoamides for their anti-QS activity using Agrobacterium tumefaciensNT1 as a biosensor strain. Among these compounds, three (2, 3and, 4) have been identified as potential anti-QS candidates. Molecular docking studies have further reinforced these findings, indicating that these compounds exhibit favorable pharmacokinetic profiles. Additionally, we have assessed the ligand's stability within the protein's binding pocket using molecular dynamics (MD) simulations and MMGBSA analysis. Further, combination of antiquorum sensing properties with antibiotics viaself-assembly represents a promising approach to enhance antibacterial efficacy, overcome resistance, and mitigate the virulence of bacterial pathogens. The release study also reflects a slow and gradual release of the metronidazole at both pH 6.5 and pH 7.4, avoiding the peaks and troughs associated with more immediate release formulations.

Preclinical evaluation of [18F]SYN1 and [18F]SYN2, novel radiotracers for PET myocardial perfusion imaging

BackgroundPositron emission tomography (PET) is now an established diagnostic method for myocardial perfusion imaging (MPI) in coronary artery disease, which is the main cause of death globally. The available tracers show several limitations, therefore, the 18F-labelled tracer is in high demand nowadays. The preclinical studies on normal Wistar rats aimed to characterise two potential, novel radiotracers, [18F]SYN1 and [18F]SYN2, to evaluate which is a better candidate for PET MPI cardiotracer.ResultsThe dynamic microPET images showed rapid myocardial uptake for both tracers. However, the uptake was higher and also stable for [18F]SYN2, with an average standardized uptake value of 3.8. The biodistribution studies confirmed that [18F]SYN2 uptake in the cardiac muscle was high and stable (3.02%ID/g at 15 min and 2.79%ID/g at 6 h) compared to [18F]SYN1 (1.84%ID/g at 15 min and 0.32%ID/g at 6 h). The critical organs determined in dosimetry studies were the small intestine and the kidneys. The estimated effective dose for humans was 0.00714 mSv/MBq for [18F]SYN1 and 0.0109 mSv/MBq for [18F]SYN2. The tested dose level of 2 mg/kg was considered to be the No Observed Adverse Effect Level (NOAEL) for both candidates. The better results were achieved for [18F]SYN2, therefore, further preclinical studies were conducted only for this tracer. Radioligand binding assays showed significant responses in 3 from 68 assays: muscarinic acetylcholine M1 and M2 receptors and potassium channel hERG. The compound was mostly metabolised via an oxidative N-dealkylation, while the fluor substituent was not separated from the molecule.Conclusion[18F]SYN2 showed a favourable pharmacodynamic and pharmacokinetic profile, which enabled a clear visualization of the heart in microPET. The compound was well-tolerated in studies in normal rats with moderate radiation exposure. The results encourage further exploration of [18F]SYN2 in clinical studies.

Discovery and optimization of 3-(indolin-5-yloxy)pyridin-2-amine derivatives as potent necroptosis inhibitors.

Necroptosis is a form of regulated necrotic cell death and has been confirmed to play pivotal roles in the pathogenesis of multiple autoimmune diseases such as rheumatoid arthritis (RA) and psoriasis. The development of necroptosis inhibitors may offer a promising therapeutic strategy for the treatment of these autoimmune diseases. Herein, starting from the in-house hit compound 1, we systematically performed structural optimization to discover potent necroptosis inhibitors with good pharmacokinetic profiles. The resulting compound 33 was a potent necroptosis inhibitor for both human I2.1 cells (IC50 < 0.2 nM) and murine Hepa1-6 cells (IC50 < 5 nM). Further target identification revealed that compound 33 was an inhibitor of receptor interacting protein kinase 1 (RIPK1) with favorable selectivity. In addition, compound 33 also exhibited favorable pharmacokinetic profiles (T1/2 = 1.32 h, AUC = 1157 ng·h/mL) in Sprague-Dawley rats. Molecular docking and molecular dynamics simulations confirmed that compound 33 could bind to RIPK1 with high affinity. In silico ADMET analysis demonstrated that compound 33 possesses good drug-likeness profiles. Collectively, compound 33 is a promising candidate for antinecroptotic drug discovery.

A phase I randomized study to evaluate safety, pharmacokinetics, and pharmacodynamics of SIR2446M, a selective RIPK1 inhibitor, in healthy participants.

Activation of receptor-interacting protein kinase 1 (RIPK1), a broadly expressed serine/threonine protein kinase, by pro-inflammatory cytokines and pathogens can result in apoptosis, necroptosis, or inflammation. RIPK1 inhibition has been shown to reduce inflammation and cell damage in preclinical studies and may have therapeutic potential for degenerative and inflammatory diseases. SIR2446 is a potent and selective novel small molecule RIPK1 kinase inhibitor. This phase I, randomized, double-blind, placebo-controlled study in Australia (ACTRN12621001621808) evaluated the safety (primary objective), pharmacokinetics, and pharmacodynamics of single (3-600 mg) and multiple (5-400 mg for 10 days) ascending oral doses of SIR2446M (SIR2446 magnesium salt form) in healthy adults from Nov 24, 2021, until May 01, 2023. All treatment-emergent adverse events (TEAEs) were mild/moderate. The most reported TEAEs were vascular access site pain, headache, and rash morbilliform. SIR2446M plasma half-lives ranged from 11 to 19 h and there were no major deviations from dose proportionality for maximum concentration and area under the curve across doses. Renal excretion of unchanged SIR2446 was minimal. No marked accumulation was observed (mean accumulation ratio, 1.2-1.6) after multiple daily doses. A high-fat meal mildly reduced the exposure but was not considered clinically significant. SIR2446M had a rapid and sustained inhibitory effect on the activity of RIPK1, with an overall 90% target engagement at repeated doses ranging from 30 to 400 mg in peripheral blood mononuclear cells exvivo stimulated to undergo necroptosis. The favorable safety, pharmacokinetic, and pharmacodynamic profile of SIR2446M in healthy participants supports its further clinical development in patients with degenerative and inflammatory diseases.

Discovery of a novel exceptionally potent and orally active Nur77 ligand NB1 with a distinct binding mode for cancer therapy

The orphan nuclear receptor Nur77 is emerging as an attractive target for cancer therapy, and activating Nur77's non-genotypic anticancer function has demonstrated strong therapeutic potential. However, few Nur77 site B ligands have been identified as excellent anticancer compounds. There are no co-crystal structures of effective anticancer agents at Nur77 site B, which greatly limits the development of novel Nur77 site B ligands. Moreover, the lack of pharmaceutical ligands restricts Nur77's therapeutic proof of concept. Herein, we developed a first-in-class Nur77 site B ligand (NB1) that significantly inhibited cancer cells by mediating the Nur77/Bcl-2-related apoptotic effect at mitochondria. The X-ray crystallography suggests that NB1 is bound to the Nur77 site B with a distinct binding mode. Importantly, NB1 showed favorable pharmacokinetic profiles and safety, as evidenced by its good oral bioavailability in rats and lack of mortality, bodyweight loss, and pathological damage at the 512.0 mg/kg dose in mice. Furthermore, oral administration of NB1 demonstrated remarkable in vivo anticancer efficacy in an MDA-MB-231 xenograft model. Together, our work discovers NB1 as a new generation Nur77 ligand that activates the Nur77/Bcl-2 apoptotic pathway with a safe and effective cancer therapeutic potency.