ACS Pharmacology & Translational Science

Coevolution proceeds through the evolution of traits that mediate ecological interactions and evolutionary outcomes. In the arms race between toxic Pacific newts (Taricha) and their garter snake predators (Thamnophis), this interface involves tetrodotoxin (TTX), an antipredator defense that inhibits nerve and muscle function by blocking voltage-gated sodium channels. In response, snakes have evolved TTX-resistant channels, in some cases leading to snake populations that are nearly invulnerable to TTX. For decades, newt TTX has been treated as a single defensive trait, yet TTX occurs as a family of structurally related analogs that may represent alternative defenses against snakes. Here, we characterize TTX analog diversity in all four species of Taricha and evaluate how these compounds interact with the sodium channels in coevolved garter snakes. Using LC-MS analysis of newt skin secretions, we detected a diverse suite of TTX analogs previously unrecognized in Pacific newts. We then used molecular docking models to evaluate interactions between various TTX analogs and variants of the skeletal muscle channel (Nav1.4) that span the range of TTX resistance in garter snakes. We found that some TTX analogs docked better than canonical TTX in resistant snake channels. Notably, we show that 11-deoxy-4-epi-TTX and 11-deoxy-TTX have favorable interactions with hydrophobic amino-acid substitutions in extremely resistant garter snake sodium channels, potentially circumventing predator resistance to canonical TTX. Our results suggest a complex arms race involving multiple newt TTX analogs and multiple snake sodium channel variants. As such, newts may keep pace with snakes by diversifying their arsenal of chemical weapons.

Background and PurposeCardiotoxicity is a major cause for drug failure throughout the drug development process, with particular concern for action potential prolongation and arrhythmia. Hence, such liabilities are heavily considered during the early phases of drug design to pre vent dangerous compounds from progressing. New approach methodologies (NAMs) that efficiently examine this risk early in the discovery pipeline should help streamline drug development programs. We developed a cardiac NAM, a 384-well open bath platform consisting of cardiac tissue derived from human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes, enabling high-throughput drug screening while maintaining the structural and functional complexity of 3D cardiac micromuscles. MethodsWe dramatically increased throughput without compromising physiological relevance provided by the 3D micromuscle structure. Our 384-well open bath high-throughput platform allowed evaluation of multiple compounds at a time, enabling us to study the CiPA (comprehensive in vitro proarrhythmia assay) drug panel for proarrhythmia screening. We obtained phenotypic fingerprints of all 28 compounds (9 low, 11 intermediate, and 8 high arrhythmia risk; https://cipaproject.org) in dose-escalation studies around their respective clinical concentrations. The analysis was augmented with an in silico pipeline that used phenotypic biomarkers to invert data into a mathematical model of cellular currents to infer which ion channels were affected upon drug exposure, and then trained a ML model to predict channel block. Results and ConclusionsWe found accurate detection of arrhythmic potential for most of the compounds, and the in silico model inversions were consistent with published values of compound channel block. All the high risk compounds showed action potential duration (APD) prolongation coupled with either action potential abnormalities, early afterdepolarizations (EADs), or beat cessation. For the intermediate risk group, 9 out of 11 compounds caused APD prolongation alone or in combination with EADs while 2 others showed either beat cessation or beat rate change. Augmentation of APD analysis with detailed biophysical modeling and ML tools provided meaningful insight into the mechanisms involved in APD changes. Overall, our cardiac NAM allowed for fast and relevant screening for mechanistic understanding of APD prolongation and proarrhythmic activity, at massively increased throughput compared to other 3D micromuscle models. SummaryCardiotoxicity testing is critical in drug development to prevent arrhythmogenic side effects. Current stringent regulations have greatly reduced market withdrawals; however, these strict evaluations often lead to costly late-stage failures and loss of promising candidates as false positives. We developed a cardiac new approach methodology (NAM), a 384-well open bath cardiac micromuscle platform created from hiPSC-derived cardiomyocytes, enabling high-throughput drug screening while maintaining the structural and functional complexity of 3D cardiac micromuscles. Using the comprehensive in vitro proarrhythmia assay (CiPA) drug panel, we validated the system to accurately detect proarrhythmic potential. Our assay provided phenotypic fingerprints based on mechanical and electrophysiological biomarkers. Integration with computational modeling offered insights into multi-ion channel effects (MICE). Particularly, we identified sodium channel block contributions as a significant factor for poor risk prediction based on traditional parameters. The combined experimental and computational platform can enhance early drug screening, thereby reducing late-stage failures and promoting the progression of low-risk compounds with complex electrophysiological profiles.

Ligand optimization is central to drug discovery as hundreds of analogs might be designed and synthesized between an initial hit and a therapeutic candidate. The efficiency of this process is unclear, at least partly because there is no random background for optimization against which to compare. Such a random background might emerge from synthetically accessible but otherwise systematic random small substitutions across starting ligands, measuring likelihood of achieving a substantial improvement in affinity/potency or other property by any single perturbation. Recent literature and ligand-affinity/potency databases suggest that perhaps 10% of analogs with minor modifications improve upon a parents potency substantially (by [≥]10-fold), but this number is clouded by reporting bias, intentional improvement, and inter-group reproducibility. To begin to establish a background expectation for ligand optimization, we comprehensively and systematically modified 18 lead molecules across six targets with single atom changes; 257 compounds were synthesized. Unexpectedly, 11.2% of these random small perturbation analogs improved potency by [≥]10-fold over their parents. Conversely, these more potent analogs typically had worse in vitro pharmacokinetics (e.g. reduced metabolic stability, lower plasma free fraction). While it was possible to find analogs where the potency increase compensated for inferior exposure and half-life, resulting in more potent compounds in vivo, overall a frustrated landscape for ligand optimization is revealed. This study begins to establish a background expectation for ligand potency optimization and offers a simple strategy to do so. It also begins to quantify the challenges confronting the field in moving beyond in vitro potency.

Opioid withdrawal is associated with heightened pain sensitivity, including allodynia. Although opioid-induced allodynia is well-documented in humans and animal models, the relationship between the severity of opioid withdrawal-induced allodynia and individual addiction-like behaviors remains poorly understood. To address this gap, Heterogeneous Stock rats underwent long access (12 hours/day) intravenous oxycodone self-administration, followed by measurement of mechanical sensitivity at six timepoints across three weeks of abstinence. Rats were stratified by an Addiction Index derived from individual differences in the escalation of oxycodone intake, motivation to consume oxycodone, tolerance to oxycodones analgesic effects, and acute withdrawal-induced mechanical pain sensitivity. Here, we show that oxycodone withdrawal induces significant and prolonged allodynia for up to three weeks, with High Addiction Index rats exhibiting greater intensity and longer duration of pain sensitivity than Low Addiction Index rats. Results remained consistent even when excluding allodynia from the Addiction Index, highlighting the robustness of the association between addiction-like severity and protracted allodynia. Linear regression associations revealed that self-administration behaviors, particularly oxycodone intake escalation and motivation to seek oxycodone, predicted subsequent withdrawal-induced allodynia severity. These findings demonstrate that greater addiction-like severity is associated with more intense and prolonged withdrawal-induced pain, supporting mechanical allodynia as a marker of addiction severity. These results motivate future work to define the mechanisms linking addiction severity to protracted opioid withdrawal-induced pain, with the goal of informing targeted clinical interventions for individuals most susceptible to severe abstinence-related allodynia.

The p21-activated kinases (PAKs) are a group of serine-threonine kinases central to multiple signaling pathways that govern cell survival and proliferation. Aberrant activity of PAK1, the most well characterized member of the PAK family, drives progression of several malignancies and brain disorders, including Alzheimers disease and neurodevelopmental disorders. Despite growing interest in PAK1 as a drug target for these diseases, there is no assay to evaluate the intracellular target engagement of PAK1 inhibitors. To address this need, we developed first-in-class NanoBRET assays for wild-type PAK1 and a neurodevelopmental disorder-causing gain-of-function PAK1 mutant. Furthermore, we executed our novel PAK1 NanoBRET assay to evaluate target engagement of PAK1 inhibitors in primary hippocampal neurons. To the best of our knowledge, this is the first demonstration of a NanoBRET cellular target engagement assay in primary neurons, thereby increasing the relevance of our work by confirming PAK1 inhibitor binding to the aberrant form of the protein in primary neurons.

CAPON (NOS1AP) is an adaptor protein involved in neuronal nitric oxide synthase (nNOS) signaling and has been implicated in Alzheimers disease (AD), excitotoxicity, and tau-associated neurodegeneration. Here, we report the identification of cyclic peptide ligands targeting CAPON using phage display screening of a disulfide-constrained peptide library. Phage enrichment, ELISA validation, microscale thermophoresis (MST), and biolayer interferometry (BLI) identified CAP1 as the lead peptide, exhibiting low micromolar binding affinity toward CAPON. Computational studies further supported stable CAPON-CAP1 interactions through complementary hydrophobic and electrostatic contacts. Functionally, CAP1 attenuated A{beta}42-induced neuronal toxicity, suppressed NMDA-driven nitric oxide production, and reduced pathological tau phosphorylation in neuronal models under AD-relevant stress conditions. In addition, CAP1 demonstrated favorable preliminary pharmacokinetic properties, including good aqueous solubility, plasma stability, and measurable membrane permeability. Collectively, these findings establish the first cyclic peptide ligands targeting CAPON and identify CAP1 as a promising scaffold for modulation of CAPON-dependent neurodegenerative signaling.

BackgroundNeuropathic pain is a major source of disability and distress with few pharmacological options for treatment. Opioid drugs can be effective, but high doses are needed, leading to unwanted effects. BMS-986122 is a positive allosteric modulator of the mu opioid receptor that potentiates acute opioid antinociception without increasing opioid-induced constipation, reward, or respiratory depression. Therefore, we asked if BMS-986122 could increase the effects of low-dose opioid analgesics in chronic neuropathic pain. MethodsWe employed the spared nerve injury and tibial neuroma models in rats and assessed the tactile hypersensitivity of the hind paw and site of neuroma, respectively. ResultsAdministration of low doses of (R)-methadone, morphine, or buprenorphine slightly reduced the tactile hypersensitivity of the hind paw the in spared nerve injury model. Pretreatment with BMS-986122 significantly enhanced the reversal of hypersensitivity, reaching the effect of high-dose gabapentin, a standard of care in neuropathic pain. Pretreatment with BMS-986122 similarly increased the anti-allodynic effects of low dose (R)-methadone on neuroma pain. A similar effect of (R)-methadone in the absence of BMS-986122 was only observed at a dose where respiratory distress was seen. ConclusionsThese findings show that allosteric modulators of the mu opioid receptor such as BMS-986122 can enhance opioid activity that could translate to a safe and effective treatment for chronic neuropathic pain.

Current treatments for opioid use disorder (OUD) have major barriers to access. As such, researching new potential therapies for OUD is important to public health. Previous research has implicated glucagon-like peptide-1 (GLP-1) receptor agonists in decreasing the use of addictive substances by animals. In this study, female Wistar rats (N=32) were surgically implanted with jugular catheters and trained to self-administer fentanyl at a fixed-ratio 1 (FR1) schedule of reinforcement for 21 sessions under short- (ShA; 1 hour) or long-access (LgA; 8 hours) conditions. Next, the animals received injections of semaglutide (0.1 mg/kg, s.c.) or saline (0.9% NaCl, s.c.) prior to another FR1 session. The animals underwent a progressive ratio (PR) schedule of reinforcement while receiving saline (i.v.) or fentanyl (0.625-10 {micro}g/kg/inf, i.v.) and semaglutide (0.1 mg/kg, s.c.) or saline (s.c.). Next, the animals underwent a semaglutide (0-0.1 mg/kg, s.c.) dose response procedure at FR1 and a single dose of fentanyl (2.5 {micro}g/kg/inf, i.v.). Following drug discontinuation, spontaneous locomotor activity and withdrawal-like symptoms were measured. Semaglutide dose-dependently decreased fentanyl rewards under ShA and LgA conditions (p<0.05). Under a PR, semaglutide significantly decreased breakpoint (p<0.05), suggesting semaglutide decreases motivation to self-administer fentanyl. Semaglutide-treated ShA animals displayed significantly less withdrawal-like behavior (p<0.05) but not LgA animals. Overall, these findings suggest semaglutide may modulate motivation to seek opioid reward and could be useful in the development of pharmacotherapies to address OUD.

Immune inhibitory signaling in microglia contributes to impaired amyloid clearance and neuroinflammation in Alzheimers disease (AD), yet small molecule modulators targeting these pathways remain largely unexplored. Here, we report the development of a high-throughput cellular thermal shift assay (HT-CETSA) platform for identification of small molecule binders targeting the inhibitory immune receptor ILT3 (LILRB4). Screening of [~]40,000 compounds yielded multiple validated hits, including IB15C, a submicromolar ILT3 binder identified through preliminary structure-activity relationship optimization. Orthogonal validation by microscale thermophoresis, surface plasmon resonance, docking, and site-directed mutagenesis confirmed direct and target-specific ILT3 engagement. Functionally, IB15C disrupted the ILT3-ApoE interaction and restored microglial activity in human iPSC-derived microglia, reducing SHP1/2, suppressing cytokine secretion, and enhancing amyloid uptake. IB15C also demonstrated favorable in vitro pharmacokinetic and safety properties, supporting further development of ILT3-targeted neuroimmune therapeutics.

The KCa2.2 and KCa3.1 channels are fundamental regulator of cellular K+ concentration, and promising target to treat diseases such as spinocerebellar ataxia and cancer. To fully exploit their therapeutic potential, and to continue studying their pathophysiological role, it is crucial to develop selective modulators for each of these two channels. Here we present a computational study to identify the molecular determinants behind the selectivity of two recently reported KCa2.2 modulators. We leveraged a protocol combining in silico mutagenesis, molecular dynamics simulations, and protein-ligand docking to analyse the pockets targeted by these ligands. We identified a Ser353/Pro245 substitution to be the main driver of the distinct pocket shapes in KCa2.2 and KCa3.1 channels, ultimately defining modulator selectivity. This approach provides novel insights into the structural differences of this binding site across potassium channel subtypes, shedding light on the selectivity determinants of modulators targeting this pocket.

TRPA1 is a non-selective cation channel that plays a crucial role in several pain and inflammatory conditions. Agents reducing membrane cholesterol decrease TRPA1 activation, but it remains unclear how cholesterol-lowering medications affect TRPA1 function. Given that TRPA1 is activated by a wide variety of chemicals, we explored whether statins have acute effects on this channel. We found that five commonly used statins activate human and mouse TRPA1 in a reversible and concentration-dependent manner. The effective concentrations were above the micromolar range, in the order: simvastatin {approx} lovastatin < fluvastatin < atorvastatin < pravastatin. Statin-induced activation was not correlated to changes in membrane order, nor mediated by N-terminal cysteine residues contributing to electrophilic compound agonism. Molecular docking calculations and the functional characterization of single-point mutants revealed two separate putative binding sites, one situated close to the kink of transmembrane segment 5 (TM5) and the other at the interface between TM4 and TM5. The mTRPA1 inhibitor A-967079 largely abrogated the response to the electrophilic agonist allyl isothiocyanate, but had weaker and varied effects across different statins and menthol. Mutation T877L strongly altered the effect of A-967079, also in an agonist-dependent manner, suggesting competitive binding between this antagonist and the non-electrophilic agonists. The identification of two distinct agonist binding sites may help explaining how TRPA1 is able to respond to a large variety of non-electrophilic compounds, while the finding of competitive interactions at one of these sites may help guide the development of agonist-specific antagonists of therapeutic relevance.

Background: Mocravimod is an oral sphingosine-1-phosphate (S1P) receptor modulator. This Phase 1 multiple-ascending-dose study evaluated its safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) in healthy volunteers. Methods: In this double-blind, randomized, placebo-controlled, parallel-group trial, 60 healthy male volunteers were enrolled in five cohorts. Mocravimod was administered once daily at 0.3, 0.6, 1.2, or 3.0 mg for 14 days, or at 2.0 mg for 28 days. Safety assessments included adverse events (AEs), laboratory tests, vital signs, electrocardiography, and Holter monitoring. PK of mocravimod and its active metabolite, mocravimod-phosphate, and PD effects on absolute lymphocyte count (ALC) and leukocyte subsets were assessed. Results: Fifty-nine of 60 participants completed the study. One participant in the 3.0 mg cohort discontinued treatment because of asymptomatic transaminase elevation. No deaths or serious AEs occurred. AEs were mostly mild or moderate, transient, and showed no clear dose relationship. Mocravimod produced dose-dependent reductions in ALC from 0.6 mg onward, with maximum geometric mean reductions of 65%, 74%, 83%, and 77% at 0.6, 1.2, 2.0, and 3.0 mg, respectively. ALC values recovered to above the lower limit of normal during follow-up in all cohorts. Holter monitoring showed an initial placebo-corrected reduction in heart rate of approximately 10-15 beats/min at doses of 1.2-3.0 mg, which attenuated with continued dosing. One participant in the 3.0 mg cohort had a recurrent daytime second-degree atrioventricular block (Mobitz I/Wenckebach), reported as a mild non-dose-limiting AE. No QT prolongation was observed. Exposure to mocravimod and mocravimod-phosphate increased approximately dose-proportionally. Steady state was reached by Day 14 (Day 28 in the 2.0 mg cohort), accumulation was approximately five- to sevenfold, terminal half-lives were approximately 100-40 hours for both analytes, and parent-to-metabolite exposure ratios were close to 1. Conclusions: Once-daily mocravimod up to 3.0 mg for 14 days and 2.0 mg for 28 days was generally well tolerated and showed predictable S1P-modulator class effects on lymphocyte counts and heart rate, with PK properties supporting once-daily dosing and further clinical development.

The use of covalent warheads targeting the catalytic cysteine has been a cornerstone in coronavirus main protease (Mpro) inhibitor development, where various electrophilic motifs have been used including aldehydes, nitriles, ketoamides, and hydroxymethyl ketones (HMKs). Recent efforts have been mostly centered around nitrile warheads, given the success of compounds like Nirmatrelvir and Ensitrelvir in the clinic. However, finding and advancing alternative chemotypes with differentiating chemical and pharmacological profiles is essential for future pandemic preparedness. Among such alternatives, HMKs hold special interest because they balance reduced intrinsic electrophilicity with an excellent selectivity profile. Nevertheless, early HMK-based compounds, such as the clinical-stage Mpro inhibitor PF-00835231, suffered from poor oral bioavailability and therefore required intravenous administration, with or without prodrug derivatization of the hydroxyl group. Here, we describe our efforts in advancing the HMK field via the discovery of mCMX110, a lead that has superior potency, increased unbound exposure in vivo, and favorable oral bioavailability in preclinical studies. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=105 SRC="FIGDIR/small/725542v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@abe1c9org.highwire.dtl.DTLVardef@746a08org.highwire.dtl.DTLVardef@dd5861org.highwire.dtl.DTLVardef@1d572c7_HPS_FORMAT_FIGEXP M_FIG C_FIG

Selective inhibition of phosphodiesterase 4B (PDE4B) remains a promising strategy for preserving the anti-inflammatory benefit of PDE4 inhibition in chronic obstructive pulmonary disease while reducing PDE4D-associated tolerability liabilities. This study integrated SHAP-interpretable machine learning, natural product virtual screening, hierarchical docking, post-docking MM-GBSA, isoform cross-docking, binding-pocket comparison, ADMET prediction, and 100 ns molecular dynamics simulations to identify PDE4B-selective inhibitors from the LOTUS natural product database. A Random Forest classifier trained on curated ChEMBL PDE4B bioactivity data achieved an external performance with AUC-ROC = 0.955, accuracy = 0.893, F1-score = 0.896, MCC = 0.785, and prioritized 119,698 predicted actives from 276,518 LOTUS compounds. SHAP analysis identified BertzCT and TPSA as major contributors to predicted activity. Sequential Lipinski, PAINS, and QED filtering retained 14,210 candidates for structure-based evaluation. Extra precision docking identified four leads with PDE4B docking scores of -9.123 to -12.080 kcal/mol, all outperforming roflumilast (-7.658 kcal/mol). Cross-docking and post-docking MM-GBSA supported preferential PDE4B binding for three candidates. The top lead, LTS0048837, maintained a stable PDE4B-bound pose during simulation, with comparatively stronger interaction persistence than its PDE4D complex and the roflumilast reference. These findings nominate LTS0048837 as a computationally prioritized PDE4B-selective natural product lead requiring experimental enzyme, cellular, and pharmacokinetic validation.

BackgroundEpidemiological studies consistently report inverse associations between caffeinated coffee consumption and dementia risk. However, the molecular mechanisms linking coffee-derived phytochemicals to neuroprotection remain only partially understood. ObjectiveTo evaluate, through integrated in silico pharmacology, the relative contribution of adenosine receptor modulation versus direct amyloidogenic enzyme and kinase inhibition in mediating the putative neuroprotective effects of major coffee constituents. MethodsMolecular docking analyses were conducted for caffeine, paraxanthine, chlorogenic acid, trigonelline, cafestol, and kahweol against adenosine A2A and A1 receptors (A2AR, A1R), {beta}-secretase 1 (BACE1), glycogen synthase kinase-3{beta} (GSK-3{beta}), and NLRP3 inflammasome components. Docking was performed using the CB-Dock2 platform. Binding affinities, interaction patterns, and ligand efficiency metrics were assessed. Blood-brain barrier permeability and ADMET properties were predicted using pkCSM. ResultsCaffeine and paraxanthine demonstrated structurally coherent binding within the orthosteric pockets of A2AR and A1R, supported by favorable predicted blood-brain barrier penetration and high unbound fractions. Ligand efficiency analysis identified adenosine receptors as the most pharmacologically plausible targets for small xanthine derivatives. Although larger phytochemicals exhibited stronger absolute docking scores at BACE1, GSK-3{beta}, and NLRP3, predicted pharmacokinetic constraints suggest a small biological effect due to a limited central exposure. ConclusionsThese findings support an adenosine receptor-centered mechanism as the dominant molecular axis linking caffeinated coffee consumption to reduced dementia risk, favoring neuroinflammatory and signaling modulation over direct enzymatic inhibition. Experimental validation is warranted to confirm translational relevance. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=193 HEIGHT=200 SRC="FIGDIR/small/723029v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@1a02629org.highwire.dtl.DTLVardef@129890dorg.highwire.dtl.DTLVardef@1e4c05corg.highwire.dtl.DTLVardef@110ec7a_HPS_FORMAT_FIGEXP M_FIG C_FIG

Cytokine release syndrome (CRS) is a major dose-limiting toxicity of T cell-engaging immunotherapies. Existing CRS models are drug-class-specific and have not addressed whether a single mechanistic cytokine network can capture severity differences across mechanistically distinct drug classes. Here, we developed a PK-driven quantitative systems pharmacology (QSP) model linking drug exposure, T cell activation dynamics, and a macrophage-amplified cytokine network to clinical CRS severity. The 17-parameter downstream amplification network with macrophage-gated STAT3 positive feedback was developed iteratively. The network was calibrated on blinatumomab, structurally refined using TGN1412 as a transparently disclosed development case, then locked and tested blind on OKT3. The same locked network was used to evaluate cross-drug transferability across three antibody-based T cell engager classes: bispecific, CD28 superagonist, and anti-CD3 with activation-induced cell death. The locked network reproduced the clinically observed CRS severity ordering across all three drugs without re-fitting any shared parameter. The OKT3 blind prediction passed eight qualitative plausibility checks and three of three quantitative cytokine peaks within published clinical ranges. Tocilizumab rescue simulation reproduced five clinically validated phenomena. A mechanistic parameter swap test reversing the T cell exhaustion rate between OKT3 and TGN1412 reversed CRS severity in the expected direction, supporting a mechanistic rather than parameter-fitted interpretation. Local robustness analysis (ABC-style accepted ensemble: 692 of 5,000 parameter sets accepted, 13.8%) and a 2D stability map over the two threshold-setting parameters (0 of 900 wrong-order combinations) confirmed that the cross-drug severity ordering is a property of a feasible parameter region rather than a single tuned point. Profile likelihood analysis of the IL-6 feedback and clearance rates revealed complementary asymmetric profiles consistent with practical identifiability as a ratio. The same locked model predicted three qualitatively distinct dose-response shapes without re-fitting. Findings should be interpreted as a mechanistic proof-of-concept; prospective clinical validation remains pending.

The rise of new, rapidly mutating viruses presents increasing challenges for drug developers. Traditional methods, such as high-throughput screening and drug repurposing against mutagenic viral targets, have recently shown their limitations. Our current rational molecular engineering approach offers a sustainable solution by targeting viral ion channels, which generally have low mutation rates. First, extending the amantadine molecule led to the development of new compounds that better match the alternating hydrophobic and hydrophilic patterns of the inner walls of ion channels--a common feature across many viruses. Then, simplifying the structure yielded a cyclohexylamine-based minimalist scaffold that effectively blocks the ion channel and demonstrates improved antiviral activity compared to well-known agents such as amantadine and arterolane. SARS-CoV-2 variants served as test systems in laboratory experiments. The new molecular scaffolds presented here provide a strong foundation for designing potent, broad-spectrum viral ion channel blockers.

BackgroundThe discontinuation of Fasiglifam (TAK-875), a GPR40/FFAR1 full agonist, during Phase 3 clinical trials due to hepatotoxicity led to widespread abandonment of GPR40 as a viable therapeutic target for type 2 diabetes mellitus (T2DM). However, mechanistic evidence suggests that Fasiglifams hepatotoxicity arises from mitochondrial liability driven by high lipophilicity (aLogP = 5.31), rather than from on-target GPR40 signaling. We hypothesized that target-level failure was incorrectly inferred from compound-level safety concerns, and that superior candidates exist within publicly available databases. MethodsWe queried ChEMBL Release 36 (28 GB SQLite, 74 tables) for all compounds with documented GPR40/FFAR1 activity (UniProt: O14842). Compounds were filtered by EC50 [&le;] 10 nM in nM units with standard relation "=". Drug-likeness was assessed using Lipinskis Rule of Five (Ro5), aLogP, molecular weight (MW), hydrogen bond donors/acceptors (HBD/HBA), and polar surface area (PSA). A parallel analysis of Therapeutic Target Database (TTD v10.1.01, 4,298 targets) provided clinical context. A real-world evidence (RWE) patient stratification framework was constructed using EMR data from tens of millions of patients with >10 years of longitudinal follow-up. ResultsOf 2,637 GPR40-active compounds in ChEMBL 36, 526 (19.9%) demonstrated EC50 < 100 nM and 102 (3.9%) demonstrated EC50 < 10 nM. Eight compounds met stringent drug-likeness criteria (Ro5 violations = 0, aLogP < 5.0, EC50 [&le;] 1 nM). The lead compound (CHEMBL4859651) exhibited EC50 = 0.04 nM (8.75-fold more potent than Fasiglifam), MW = 297 Da (43% lower), and aLogP = 4.30 (19% lower), with zero Ro5 violations. Mean MW of the eight candidates was 317 {+/-} 28 Da versus 524 Da for Fasiglifam. A parallel GCK analysis identified a protein-protein interaction target (CHEMBL3885579, GCK-GKRP interface) harboring 40 exclusive compounds as an orthogonal strategy for partial GCK activation. ConclusionsSystematic cheminformatic analysis reveals that compounds with substantially superior activity and drug-likeness profiles relative to Fasiglifam exist within ChEMBL 36. Fasiglifams hepatotoxicity is attributable to compound-specific physicochemical properties, not GPR40-mediated toxicity. RWE patient stratification may further mitigate hepatotoxicity risk for next-generation GPR40 agonists. These findings argue for systematic reappraisal of GPR40 as a viable therapeutic target for T2DM.

Drug-induced seizures remain a major safety concern in drug development, yet human seizure liability is difficult to predict using conventional preclinical models. Here, we evaluated whether spontaneous calcium network activity in human induced pluripotent stem cell-derived CNS-3D Brain Organoids could predict clinically observed seizure risk across a pharmacokinetically anchored drug set. CNS-3D organoids contained neuronal and astrocytic populations, expressed neuroactive receptor and ion-channel gene programs that aligned with human cortical tissue, and exhibited reproducible spontaneous calcium oscillations across production batches. A retrospective drug panel of 66 small-molecule drugs was assembled from human clinical evidence, including 30 seizure-associated drugs and 36 comparator drugs without documented clinical seizure liability. Drugs were tested across concentration ranges anchored to reported clinical Cmax, and calcium time-series responses were integrated with chemical structure features using a machine-learning workflow. The final model predicted clinical seizure liability with an AUROC of 0.872, achieving 83.3% sensitivity and 88.9% specificity in drug-level cross-validation. Model scores also stratified seizure-associated drugs by clinical context and prevalence, suggesting that CNS-3D activity profiles capture clinically meaningful differences in seizure risk. Compared with published in vitro and preclinical seizure-liability models, CNS-3D organoid-based predictions showed improved balanced sensitivity and specificity. These findings support high-throughput calcium profiling in human CNS-3D organoids as a scalable, exposure-aware platform for predicting human seizure liability and contributing functional human data to neuro-safety assessment.

Background and PurposeWhile inflammation has been generally considered to exacerbate symptoms of schizophrenia, some clinical observations suggest that acute inflammation may alleviate positive symptoms. However, animal models often use excessive inflammatory stimuli, and the effects of acute inflammation--comparable to levels observed in patients--remain unknown. Experimental ApproachTo address this, we examined whether acute inflammation induced under relatively mild, clinically relevant conditions suppresses behavioural sensitization in methamphetamine (METH)-sensitized mice, a model of psychostimulant-induced psychosis with relevance to certain aspects of positive symptoms of schizophrenia. We used a repeated METH (1 mg/kg) sensitized model to evaluate the effects of acute inflammation on behavioural sensitization. Acute inflammation was induced via two methods using either lipopolysaccharides (LPS; 1 g/kg) to mimic peripheral immune activation or restraint stress (RS; single 2-h exposure) to model the neuroinflammation induced by psychological stress. LPS doses were adjusted with reference to the magnitude of peripheral cytokine elevation reported in patients, and RS was applied in short single sessions to avoid excessive inflammation. Key ResultsBoth LPS and RS significantly suppressed behavioural sensitization, without inducing other behavioural abnormalities. This suppression was dependent on toll-like receptor-4 activation. LPS-mediated suppression involved cyclooxygenase-2, whereas RS-mediated suppression was linked to the microglia-derived tumour necrosis factor-. LPS did not alter, whereas RS significantly reduced the striatal extracellular dopamine levels. Conclusion and ImplicationsThese findings suggest that acute inflammation suppresses behavioural sensitization through distinct mechanisms depending on the inflammatory trigger, providing a framework for understanding how inflammation may influence psychosis-related processes, with potential relevance to schizophrenia.