A series of -(1,2,3,4-tetrahydro-3-isoquinolinylmethyl)benzamides, which are potent μ-opioid receptor (MOR) agonists, has been discovered. The most promising compound, compound (BPR1M492), is an MOR agonist without a cl...A series of -(1,2,3,4-tetrahydro-3-isoquinolinylmethyl)benzamides, which are potent μ-opioid receptor (MOR) agonists, has been discovered. The most promising compound, compound (BPR1M492), is an MOR agonist without a clear signaling bias between cAMP and β-arrestin-2 pathways, a cAMP-biased nociceptin-orphanin FQ opioid peptide agonist, and a weak cAMP-biased δ/κ-opioid receptor agonist. Compound demonstrated potent antinociception at 0.027 mg/kg, offering rapid pain relief within 5 min of subcutaneous injection. It produced markedly milder withdrawal symptoms than TRV130 in mice, whereas differences in respiratory, gastrointestinal, reward-related, and tolerance-related measures were less pronounced and should be interpreted cautiously in light of the substantially lower dose required for antinociception. Compound is a highly stable, slightly hygroscopic, low-moisture-containing crystalline solid that is safe at its effective dose.
Acute myeloid leukemia (AML) remains a therapeutic challenge due to its aggressive nature and poor prognosis in relapsed/refractory cases. This study explores novel MNK (MAP kinase-interacting kinase) inhibitors derived...Acute myeloid leukemia (AML) remains a therapeutic challenge due to its aggressive nature and poor prognosis in relapsed/refractory cases. This study explores novel MNK (MAP kinase-interacting kinase) inhibitors derived from the marine natural product phorbazole C. Through systematic structure-activity relationship studies, compound (YTB53) was identified as a potent MNK1/2-targeting compound with IC values of 0.037 and 0.009 μM, respectively. Kinase profiling further revealed that also significantly inhibits PDGFRα, TRKB and FLT3, indicating that its antiproliferative activity in MV4-11 cells arises from multikinase engagement rather than selective MNK inhibition alone. Mechanistically, induced cell cycle arrest, apoptosis, pyroptosis, and mitochondrial dysfunction. It also exhibited antiangiogenic effects and suppressed tumor growth in a xenograft model without overt toxicity. These findings support as a promising multimechanistic lead for AML therapy, warranting further medicinal chemistry optimization to improve its pharmacokinetic properties and advance its development potential.
Programmed death-ligand 1 (PD-L1) is a key mediator of tumor immune evasion and plays a critical role in tumor immunodiagnosis and immunotherapy. We developed a PD-L1-targeted peptide PET tracer, Ga-PDT01, incorporating...Programmed death-ligand 1 (PD-L1) is a key mediator of tumor immune evasion and plays a critical role in tumor immunodiagnosis and immunotherapy. We developed a PD-L1-targeted peptide PET tracer, Ga-PDT01, incorporating a 2-substituted naphthyl group and 5-(trifluoromethyl)nicotinic acid to enhance tumor uptake and retention. Ga-PDT01 exhibited moderate binding affinity ( = 304 ± 26 nM) and specific uptake in PD-L1-positive cells, which was blocked by excess unlabeled peptide. PET imaging demonstrated clear tumor visualization in multiple subcutaneous tumor models with tumor-to-muscle ratios >6.00 at 1 h postinjection. Tracer uptake increased ∼3.16-fold following cisplatin-induced PD-L1 upregulation, indicating sensitivity to dynamic PD-L1 modulation. These findings suggest that Ga-PDT01 enables accurate, noninvasive assessment of PD-L1 expression and holds translational potential for guiding PD-L1-targeted diagnosis and therapeutic monitoring.
Jain S, Yasgar A, Dalal A
… +13 more, Nilova A, Davies M, Baljinnyam B, Qu Y, Denson JP, Esposito D, Tao D, Yang SM, Talley DC, Simeonov A, Martinez NJ, Rai G, Zakharov AV
Developing potent, selective small-molecule inhibitors remains a major challenge in drug discovery. ALDH3A1, a detoxifying aldehyde dehydrogenase isoform implicated in cancer and neurodegeneration, is a promising yet und...Developing potent, selective small-molecule inhibitors remains a major challenge in drug discovery. ALDH3A1, a detoxifying aldehyde dehydrogenase isoform implicated in cancer and neurodegeneration, is a promising yet underexplored therapeutic target. To accelerate inhibitor optimization, we developed an AI-guided, reaction-based hit-to-lead workflow combining sequential reaction enumeration, pharmacophore-informed docking, and predictive modeling to support scalable SAR expansion. Applied to ALDH3A1, two rounds of enumeration using Enamine building blocks generated about 250,000 virtual analogues. Combined deep learning and docking-based triage prioritized 150 compounds for synthesis, leading to a roughly 1,000-fold improvement in biochemical potency from 1.41 μM to 1 nM for NCATS-SM0707, together with 4 nM cellular activity for NCATS-SM0708. Crucially, this methodology can be expanded by applying various chemical reactions at different positions. This study highlights CSAR as a scalable, generalizable complementary strategy to accelerate hit optimization through reaction-based enumeration and AI-guided prioritization of larger synthetically accessible chemical space.
Targeted inhibition of monoacylglycerol lipase (MAGL) represents a promising therapeutic strategy for inflammatory diseases and drug-induced hepatotoxicity. However, the lack of robust screening assays hindered the effic...Targeted inhibition of monoacylglycerol lipase (MAGL) represents a promising therapeutic strategy for inflammatory diseases and drug-induced hepatotoxicity. However, the lack of robust screening assays hindered the efficient discovery of potent MAGL inhibitors. Herein, a high-performance MAGL-activatable fluorogenic probe, CN-2, was developed through three-round structural optimization of luminescent scaffold, -site substituent, and recognition moiety. CN-2 displayed an optimal combination of signal enhancement, detection sensitivity, and favorable kinetic behaviors. CN-2-based high-throughput screening platform efficiently identified three potent competitive MAGL inhibitors (A5, A11, and F10). These inhibitors potently inhibited intracellular MAGL activity in macrophages, significantly elevated endogenous 2-AG levels, and attenuated LPS-induced inflammatory responses. Furthermore, these agents conferred significant hepatoprotective effects against acetaminophen (APAP)-induced injury in both hepatocytes and human liver organoids by reducing ALT, AST, LDH, and ROS, and restoring mitochondrial membrane potential. Collectively, this work establishes a practical and efficient platform for discovering MAGL inhibitors as novel anti-inflammatory and hepatoprotective agents.
Nuclear factor erythroid 2-related factor 2 (Nrf2) is a pleiotropic transcription factor essential for cellular defense. Extensive research has demonstrated its oncogenic role, positioning Nrf2 as a promising target for...Nuclear factor erythroid 2-related factor 2 (Nrf2) is a pleiotropic transcription factor essential for cellular defense. Extensive research has demonstrated its oncogenic role, positioning Nrf2 as a promising target for cancer therapy. However, achieving tumor-specific Nrf2 inhibition remains a challenge. Herein, we report the discovery of , a biased inhibitor of Kelch-like ECH-associated protein 1-phosphorylated p62 (Keap1--p62) interaction, as a selective and effective Nrf2 inhibitor. In fluorescence polarization assays, showed potent Keap1--p62 inhibitory activity (IC = 0.11 μM) and high selectivity over the inhibition of Keap1-Nrf2 interaction. Notably, specifically inhibited Nrf2 activity in p62 aberrant hepatocellular carcinoma (HCC) cells by selectively disrupting Keap1--p62 interaction and normalizing Nrf2 ubiquitination. Furthermore, cotreatment with sensitized p62 aberrant HCC to ferroptosis induced by sorafenib (TGI = 95.3%). Overall, our study identifies a biased Keap1--p62 inhibitor as a targeted Nrf2 inhibition therapy and provides valuable insights into HCC treatment.
This study identified 6-24, a novel antiarrhythmic lead derived from the roemerine scaffold, which exhibited a distinctive multichannel blockade profile targeting Nav1.5 and Cav1.2, while demonstrating only weak inhibiti...This study identified 6-24, a novel antiarrhythmic lead derived from the roemerine scaffold, which exhibited a distinctive multichannel blockade profile targeting Nav1.5 and Cav1.2, while demonstrating only weak inhibition of hERG. This gentle multitarget profile avoided excessive single-channel blockade associated with proarrhythmic drugs, conferring low QT prolongation risk, a key advantage over agents like verapamil. Patch-clamp and iPSC-cardiomyocyte MEA confirmed prolonged action potentials and reduced conduction velocity. Multielectrode mapping in isolated hearts further revealed that the compound dose-dependently prolonged ventricular activation time and reduced conduction velocity, accompanied by a decrease in the heart rate, without significantly altering the QTc interval. Pharmacokinetic analysis further established that this active concentration could be achieved clinically. Beyond electrophysiological modulation, uniquely restored cardiac function , normalizing ventricular dimensions and hemodynamics. With integrated efficacy, safety, and functional restoration, represented a promising multitarget candidate for ventricular arrhythmia therapy.
Discovering novel kinase modulators that combine high selectivity with the ability to regulate noncatalytic functions remains a crucial goal in kinase drug discovery. Here, we use Aurora A as a case study to demonstrate...Discovering novel kinase modulators that combine high selectivity with the ability to regulate noncatalytic functions remains a crucial goal in kinase drug discovery. Here, we use Aurora A as a case study to demonstrate that proteolysis-targeting chimeras (PROTACs) provide a compelling solution to these challenges. We discovered , a potent, selective and in vivo active Aurora A PROTAC degrader, developed from a promiscuous kinase inhibitor warhead. potently degrades Aurora A with a DC value of 2.3 nM in MD-MBA-231 cells and demonstrates exceptional selectivity in a global proteomic analysis. Furthermore, effectively depletes Aurora A in vivo. This study presents a valuable chemical tool for probing the noncatalytic biology of the kinase and, importantly, highlights that selective kinase degraders are achievable even from promiscuous binding ligands.
Phosphoglycerate kinase 1 (PGK1), the first ATP-generating enzyme in glycolysis, is frequently overexpressed in a wide range of human malignancies. Beyond its canonical glycolytic function, PGK1 also functions as a prote...Phosphoglycerate kinase 1 (PGK1), the first ATP-generating enzyme in glycolysis, is frequently overexpressed in a wide range of human malignancies. Beyond its canonical glycolytic function, PGK1 also functions as a protein kinase playing a critical role in tumorigenesis and cancer progression. Here, we report the identification of a novel and highly potent PGK1 inhibitor through structure-based high-throughput virtual screening, exemplified by compound (C67-47). C67-47 binds strongly to PGK1 with a dissociation constant () of 63 nM and exhibits potent antiproliferative effects in pancreatic cancer cells. In preclinical studies, C67-47 demonstrated excellent oral pharmacokinetics in both mouse and rat models. Strikingly, a single oral dose of C67-47 resulted in up to 80% tumor growth inhibition in pancreatic cancer xenograft models with no observable toxicity. These findings establish C67-47 as a promising lead compound for the development of orally administered, PGK1-targeted therapies for pancreatic cancer.
The quinoline scaffold, a well-established privileged structure, continues to play a central role in antimalarial drug discovery. This perspective presents a comprehensive summary and discussion of the antimalarial targe...The quinoline scaffold, a well-established privileged structure, continues to play a central role in antimalarial drug discovery. This perspective presents a comprehensive summary and discussion of the antimalarial targets of quinoline derivatives, including heme detoxification, CDPK1, ChoK, PI4K, PK6, proteases, LDH, HSP, CRT, eEF2, PFT, and the cytochrome bc1 complex. Particular emphasis is placed on promising analogs with dual-stage or multistage activity, potent efficacy against drug-resistant strains, and favorable physicochemical and pharmacokinetic profiles, together with robust performance. Emerging safety considerations, such as cardiotoxicity (hERG inhibition), hepatotoxicity, and metabolite formation, are also highlighted. In addition, key challenges and future directions are discussed, including exploration of new biological targets and the application of modern discovery strategies such as molecular hybridization, drug repurposing, prodrug design, and ionic liquids. Overall, this perspective aims to provide insights that support the continued development of affordable, safe, and effective quinoline-based antimalarial therapeutics.
Torrente E, Quotadamo A, Corio A
… +14 more, Ferrigno F, Ievoli G, Montalbetti C, Vasile S, Graziani R, Paonessa G, Alli C, Bisbocci M, Veneziano M, Proto G, Orsale MV, di Marco A, Toniatti C, Ontoria JM
Zika virus is an increasing medical and socio-economic burden in (sub)tropical regions, with no effective treatments available. Previously, we identified a novel series of -carbamoylsydnone imine derivatives as potent ZI...Zika virus is an increasing medical and socio-economic burden in (sub)tropical regions, with no effective treatments available. Previously, we identified a novel series of -carbamoylsydnone imine derivatives as potent ZIKV NS2B-NS3 protease inhibitors through phenotypic antiviral screening. Here, we report the optimization of this series, leading to , a nanomolar inhibitor active in both biochemical and cellular assays, exhibiting no cytotoxicity. demonstrates favorable oral bioavailability, low clearance, and strong prophylactic efficacy in mouse models of ZIKV infection. These results highlight as a promising therapeutic candidate against ZIKV and a potential foundation for developing broad-spectrum orthoflavirus agents.
The norepinephrine transporter (NET) represents a validated target for theranostics in neuroendocrine tumors, yet clinical agents such as [I]/[I]mIBG exhibit suboptimal tumor retention, deiodination, and dose-limiting to...The norepinephrine transporter (NET) represents a validated target for theranostics in neuroendocrine tumors, yet clinical agents such as [I]/[I]mIBG exhibit suboptimal tumor retention, deiodination, and dose-limiting toxicity. To address these limitations, we designed and synthesized a series of radioiodinated phenoxyalkylguanidine (PhOG) derivatives by replacing the conventional benzyl moiety with a phenoxyalkyl spacer to increase tumor uptake and enhance metabolic stability. The -I-PhOG was efficiently prepared (RCY 45%, RCP >98%) and exhibited enhanced NET affinity and prolonged intracellular retention compared to [I]mIBG. In PC-12 xenograft models, -I-PhOG achieved significantly higher tumor uptake and superior SPECT/CT contrast. At half the dose, -I-PhOG exerted comparable tumor growth inhibition (TGI = 92.9%) to 10.0 MBq [I]mIBG, with prolonged survival and no obvious toxicity. These results underscore that the strategic incorporation of a phenoxyalkyl linker improves the pharmacokinetic and therapeutic profiles of NET-targeted radiopharmaceuticals, positioning -I-PhOG as a promising candidate for neuroendocrine tumor theranostics.
Androgenetic alopecia (AGA) is primarily driven by overexpression of androgen receptor (AR) in hair follicles, leading to androgen hypersensitivity and progressive follicular miniaturization. Although PROTAC degraders of...Androgenetic alopecia (AGA) is primarily driven by overexpression of androgen receptor (AR) in hair follicles, leading to androgen hypersensitivity and progressive follicular miniaturization. Although PROTAC degraders offer the potential for sustained AR downregulation, their application in AGA has been limited by poor solubility and skin permeability. In this study, we incorporated pyridazinyl glutarimide (PDG) moiety as a novel CRBN ligand and developed dAR-6-1, a PROTAC with both potent AR degradation activity (DC = 0.90 nM, = 91% in LNCaP; DC = 0.23 nM, = 90% in hDPC) and exceptional aqueous solubility ( > 500 mg·mL). Both porcine skin permeation and mouse studies confirmed the favorable skin permeability of dAR-6-1. In the AGA mouse model, topical application of dAR-6-1 resulted in superior hair regeneration compared to minoxidil. These results establish dAR-6-1 as a promising candidate and provide a valuable design strategy for transdermal PROTACs.
Guha R, Wang W, Price E
… +13 more, Bhhatarai B, Hassan M, DiFranzo A, Keefer C, Woody N, Broccatelli F, Winiwarter S, He L, Green DVS, Edwards CD, Kato H, Kosugi Y, Desai P
Machine learning models for ADMET prediction benefit from large, diverse data sets, yet such data are typically siloed across organizations. Federated learning (FL) enables collaborative modeling while preserving data pr...Machine learning models for ADMET prediction benefit from large, diverse data sets, yet such data are typically siloed across organizations. Federated learning (FL) enables collaborative modeling while preserving data privacy. Here, we investigate a student-teacher model (STM) framework in which organizations train internal models on proprietary data and share predictions on a public data set to generate pseudolabels for a centralized student model. As a proof of concept, 11 pharmaceutical companies contributed predictions for rat steady-state volume of distribution, yielding a pseudolabeled data set of ∼133,000 compounds. The resulting student model achieved performance comparable to individual teacher models on an external test set (RMSE ≈ 0.51 vs 0.47-0.61). Compared with FL approaches such as MELLODY and Effiris, STM offers a simpler workflow that avoids direct data sharing or iterative collaboration, providing a practical and scalable framework for secure cross-company model development.
Gajendran N, Suresh M, Marquez R SJ
… +14 more, Mohan S, Ponsot T, Quiceno-Torres D, Noboa MA, Weselman BT, Li X, Durr M, Novakova Z, Schutkowski M, Hepp M, Noonepalle S, Barinka C, Wardrop DJ, Villagra A
Tumor-associated macrophages (TAMs) play a pivotal role in shaping the tumor microenvironment (TME) and influencing the outcomes of immunotherapy. However, most drug screening strategies emphasize tumor cell cytotoxicity...Tumor-associated macrophages (TAMs) play a pivotal role in shaping the tumor microenvironment (TME) and influencing the outcomes of immunotherapy. However, most drug screening strategies emphasize tumor cell cytotoxicity and neglect immune effector modulation. Here, we describe a macrophage-centric phenotypic screening platform to identify selective HDAC6 inhibitors that reprogram TAMs toward an antitumor phenotype. Building on the HDAC6 inhibitor SS-208, we synthesized a novel class of tetrazolone-based compounds with potent selectivity and minimal cytotoxicity. Among these, SM-06-09 emerged as a lead candidate, showing subnanomolar HDAC6 inhibition, enhanced macrophage phagocytosis, antigen presentation, and T-cell activation in vitro. In a syngeneic melanoma model, SM-06-09 suppressed tumor growth and promoted M1-like TAM polarization. Combination with anti-PD-1 therapy further enhanced immune infiltration, increased effector memory and central memory T-cells, and improved antitumor efficacy. This study establishes a functional screening framework for identifying immunomodulatory compounds and supports the clinical potential of macrophage-targeted HDAC6 inhibitors as adjuncts to immune checkpoint blockade.
Protein-protein interactions (PPIs) are promising drug targets, yet peptide modulation of intracellular PPIs is limited by poor membrane permeability. Although conjugation with cell-penetrating peptides (CPPs) improves d...Protein-protein interactions (PPIs) are promising drug targets, yet peptide modulation of intracellular PPIs is limited by poor membrane permeability. Although conjugation with cell-penetrating peptides (CPPs) improves delivery, it often increases molecular weight, induces nonspecific interactions, and compromises target binding. Here, we present a CPP grafting strategy that integrates membrane permeability into peptide design while preserving binding capability. Based on computational identification of hotspot residues, CPP motifs were embedded into regions dispensable for binding. Applied to the MDM2/p53 interaction, the CPP-grafted stapled peptide showed enhanced cellular uptake and improved intracellular inhibitory activity compared with CPP-conjugated analogues. X-ray crystallography confirmed the preservation of key hydrophobic hotspot residues after grafting. The strategy was also validated in the β-catenin/TCF system, where CPP-grafted peptides retained binding affinity, suppressed Wnt signaling, and inhibited cancer cell proliferation. This approach provides a structure-guided platform for intracellular PPI-targeting peptides.
Opioid-related overdoses have continued to rise in the past decade and have been further exacerbated by polydrug exposure involving the α adrenergic receptor agonist xylazine, a veterinary tranquilizer referred to as "tr...Opioid-related overdoses have continued to rise in the past decade and have been further exacerbated by polydrug exposure involving the α adrenergic receptor agonist xylazine, a veterinary tranquilizer referred to as "tranq" or "tranq dope". Despite the growing threat of xylazine and other α adrenergic receptor agonists, no FDA-approved treatment or prophylaxis exists for xylazine-induced overdose toxicity in humans. To address this unmet need, our team developed and characterized a series of novel xylazine-based haptens and their cognate conjugate vaccines. This study tested their efficacy against xylazine-induced pharmacological effects in rats. Our results demonstrated that active immunization provides protection against xylazine by limiting its entry into the brain and mitigating its pharmacological effects. This study also provides preliminary evidence that a xylazine vaccine can be combined with a fentanyl vaccine through a multivalent formulation strategy to provide protection against drug mixtures of xylazine and synthetic opioids. These findings highlight the potential for immunotherapeutics to prevent toxicity resulting from xylazine and polydrug exposure.
Halogenation has been used as a useful strategy to optimize an imidazolium-based macrocyclic ultralong-acting neuromuscular blocking agent for improved bioactivity and biocompatibility. A structure-activity relationship...Halogenation has been used as a useful strategy to optimize an imidazolium-based macrocyclic ultralong-acting neuromuscular blocking agent for improved bioactivity and biocompatibility. A structure-activity relationship study for 18 compounds reveals that monofluorinated macrocycle displays blockade profiles generally superior to those of lead compound . In vivo tests with a rat model show that, compared with those of , the onset, profound blockade, and moderate blockade-to-spontaneous respiration times of at the same dose of 0.2 mg/kg shortens by 47%, extends by 34%, and shortens by 89%, respectively, while the onset activity surpasses that of cisatracurium, one of the main neuromuscular blocking agents, of a clinically associated dose. Moreover, the profound blockade of can be rapidly reversed by a biocompatible acyclic cucurbit[]uril (ACB) antagonist at any stage of blockade. also exhibits a biosafety superior to that of . The two agents thus form a promising partnership featuring ultralong-acting blockade and on-demand reversal.
Fibroblast activation protein (FAP) is highly expressed in cancer-associated fibroblasts and represents an attractive target for PET imaging. Here, we report [F]AlF-, an improved FAPI-46 derivative bearing an -methyl-ben...Fibroblast activation protein (FAP) is highly expressed in cancer-associated fibroblasts and represents an attractive target for PET imaging. Here, we report [F]AlF-, an improved FAPI-46 derivative bearing an -methyl-benzenesulfonic acid side chain and labeled via an Al[F]-NOTA platform. [F]AlF- was obtained with high radiochemical purity (>95%), high FAP binding affinity (IC = 2.94 nM), and high hydrophilicity (LogD = -3.06). In A549-hFAP xenografts, PET imaging showed high tumor uptake (7.45 ± 2.34%ID/g at 60 min), rapid renal clearance, and low hepatobiliary background, with strong concordance between PET-derived uptake and ex vivo biodistribution. In a first-in-human study, physiologic uptake decreased over time, whereas tumor uptake persisted to 120 min. The effective dose was 0.03 ± 0.01 mSv/MBq. Malignant lesions exhibited higher target-to-background ratios on [F]AlF- PET/CT than on [F]FDG and [F]FAPI-42. Collectively, these findings support the clinical translation potential of [F]AlF-, which combines high affinity with excellent imaging contrast.
No selective actin inhibitor has been developed due to the high homology of actin isoforms. Given the distributions of cysteine residues among actin isoforms, we propose the covalent small-molecule targeting approach off...No selective actin inhibitor has been developed due to the high homology of actin isoforms. Given the distributions of cysteine residues among actin isoforms, we propose the covalent small-molecule targeting approach offers a distinct path to achieve isoform selectivity. Combining phenotypic screening of our in-house covalent compound library and structural optimizations, we identified a novel and selective β-actin inhibitor . ABPP protein affinity enrichment and mechanistic investigations discovered specifically targeted to β-actin but not α- or γ-actin and inhibited its polymerization to disrupt the actin cytoskeleton and lead to cell death in143B cells. exhibits potent anticancer activity both (IC = 0.015 μM) and (TGI = 66%) and shows no obvious toxicity at the tested dosage. To our knowledge, represents the first selective inhibitor of β-actin. This provides valuable insights and a foundation for subsequent research on the selectivity of actins and related drug discovery.