RESUMEN
Pharmacodynamic (PD) studies are an essential component of preclinical drug discovery. Current approaches for PD studies, including the analysis of novel kidney disease targeting therapeutic agents, are limited to animal models with unclear translatability to the human condition. To address this challenge, we developed a novel approach for PD studies using transplanted, perfused human kidney organoids. We performed pharmacokinetic (PK) studies with GFB-887, an investigational new drug now in phase 2 trials. Orally dosed GFB-887 to athymic rats that had undergone organoid transplantation resulted in measurable drug exposure in transplanted organoids. We established the efficacy of orally dosed GFB-887 in PD studies, where quantitative analysis showed significant protection of kidney filter cells in human organoids and endogenous rat host kidneys. This widely applicable approach demonstrates feasibility of using transplanted human organoids in preclinical PD studies with an investigational new drug, empowering organoids to revolutionize drug discovery.
Asunto(s)
Enfermedades Renales , Organoides , Animales , Descubrimiento de Drogas , Drogas en Investigación , Humanos , Riñón , RatasRESUMEN
Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent monogenic human disease, but to date, only one therapy (tolvaptan) is approved to treat kidney cysts in ADPKD patients. Cyclin-dependent kinase 5 (CDK5), an atypical member of the cyclin-dependent kinase family, has been implicated as a target for treating ADPKD. However, no compounds have been disclosed to date that selectively inhibit CDK5 while sparing the broader CDK family members. Herein, we report the discovery of CDK5 inhibitors, including GFB-12811, that are highly selective over the other tested kinases. In cellular assays, our compounds demonstrate CDK5 target engagement while avoiding anti-proliferative effects associated with inhibiting other CDKs. In addition, we show that the compounds in this series exhibit promising in vivo PK profiles, enabling their use as tool compounds for interrogating the role of CDK5 in ADPKD and other diseases.
Asunto(s)
Quinasa 5 Dependiente de la Ciclina/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/síntesis química , Proliferación Celular/efectos de los fármacos , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Diseño de Fármacos , Descubrimiento de Drogas , Células HEK293 , Humanos , Modelos Moleculares , Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Relación Estructura-Actividad , Especificidad por SustratoRESUMEN
We identified a genetic variant, an 8-residue appendage, of the α345 hexamer of collagen IV present in patients with glomerular basement membrane diseases, Goodpasture's disease and Alport syndrome, and determined the long-awaited crystal structure of the hexamer. We sought to elucidate how variants cause glomerular basement membrane disease by exploring the mechanism of the hexamer assembly. Chloride ions induced in vitro hexamer assembly in a composition-specific manner in the presence of equimolar concentrations of α3, α4, and α5 NC1 monomers. Chloride ions, together with sulfilimine crosslinks, stabilized the assembled hexamer. Furthermore, the chloride ion-dependent assembly revealed the conformational plasticity of the loop-crevice-loop bioactive sites, a critical property underlying bioactivity and pathogenesis. We explored the native mechanism by expressing recombinant α345 miniprotomers in the cell culture and characterizing the expressed proteins. Our findings revealed NC1-directed trimerization, forming protomers inside the cell; hexamerization, forming scaffolds outside the cell; and a Cl gradient-signaled hexamerization. This assembly detail, along with a crystal structure, provides a framework for understanding hexamer dysfunction. Restoration of the native conformation of bioactive sites and α345 hexamer replacement are prospective approaches to therapeutic intervention.
Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular/genética , Colágeno Tipo IV/química , Colágeno Tipo IV/metabolismo , Mutación , Nefritis Hereditaria/genética , Multimerización de Proteína , Línea Celular , Colágeno Tipo IV/genética , Estructura Cuaternaria de ProteínaRESUMEN
Leveraging the catalytic machinery of LSD1 (KDM1A), a series of covalent styrenylcyclopropane LSD1 inhibitors were identified. These inhibitors represent a new class of mechanism-based inhibitors that target and covalently label the FAD cofactor of LSD1. The series was rapidly progressed to potent biochemical and cellular LSD1 inhibitors with good physical properties. This effort resulted in the identification of 34, a highly potent (<4 nM biochemical, 2 nM cell, and 1 nM GI50), and selective LSD1 inhibitor. In-depth kinetic profiling of 34 confirmed its covalent mechanism of action, validated the styrenylcyclopropane as an FAD-directed warhead, and demonstrated that the potency of this inhibitor is driven by improved non-covalent binding (K I). 34 demonstrated robust cell-killing activity in a panel of AML cell lines and robust antitumor activity in a Kasumi-1 xenograft model of AML when dosed orally at 1.5 mg/kg once daily.
RESUMEN
The nonselective Ca2+-permeable transient receptor potential (TRP) channels play important roles in diverse cellular processes, including actin remodeling and cell migration. TRP channel subfamily C, member 5 (TRPC5) helps regulate a tight balance of cytoskeletal dynamics in podocytes and is suggested to be involved in the pathogenesis of proteinuric kidney diseases, such as focal segmental glomerulosclerosis (FSGS). As such, protection of podocytes by inhibition of TRPC5 mediated Ca2+ signaling may provide a novel therapeutic approach for the treatment of proteinuric kidney diseases. Herein, we describe the identification of a novel TRPC5 inhibitor, GFB-8438, by systematic optimization of a high-throughput screening hit, pyridazinone 1. GFB-8438 protects mouse podocytes from injury induced by protamine sulfate (PS) in vitro. It is also efficacious in a hypertensive deoxycorticosterone acetate (DOCA)-salt rat model of FSGS, significantly reducing both total protein and albumin concentrations in urine.
RESUMEN
A high-throughput screening (HTS) of the Genentech/Roche library identified a novel, uncharged scaffold as a KDM5A inhibitor. Lacking insight into the binding mode, initial attempts to improve inhibitor potency failed to improve potency, and synthesis of analogs was further hampered by the presence of a C-C bond between the pyrrolidine and pyridine. Replacing this with a C-N bond significantly simplified synthesis, yielding pyrazole analog 35, of which we obtained a co-crystal structure with KDM5A. Using structure-based design approach, we identified 50 with improved biochemical, cell potency and reduced MW and lower lipophilicity (LogD) compared with the original hit. Furthermore, 50 showed lower clearance than 9 in mice. In combination with its remarkably low plasma protein binding (PPB) in mice (40%), oral dosing of 50 at 5mg/kg resulted in unbound Cmax â¼2-fold of its cell potency (PC9 H3K4Me3 0.96µM), meeting our criteria for an in vivo tool compound from a new scaffold.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Ensayos Analíticos de Alto Rendimiento , Pirazoles/farmacología , Proteína 2 de Unión a Retinoblastoma/antagonistas & inhibidores , Administración Oral , Animales , Disponibilidad Biológica , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Humanos , Ratones , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Simulación del Acoplamiento Molecular , Estructura Molecular , Pirazoles/administración & dosificación , Pirazoles/química , Ratas , Proteína 2 de Unión a Retinoblastoma/metabolismo , Relación Estructura-ActividadRESUMEN
Polycomb repressive complex 2 (PRC2) has been shown to play a major role in transcriptional silencing in part by installing methylation marks on lysine 27 of histone 3. Dysregulation of PRC2 function correlates with certain malignancies and poor prognosis. EZH2 is the catalytic engine of the PRC2 complex and thus represents a key candidate oncology target for pharmacological intervention. Here we report the optimization of our indole-based EZH2 inhibitor series that led to the identification of CPI-1205, a highly potent (biochemical IC50 = 0.002 µM, cellular EC50 = 0.032 µM) and selective inhibitor of EZH2. This compound demonstrates robust antitumor effects in a Karpas-422 xenograft model when dosed at 160 mg/kg BID and is currently in Phase I clinical trials. Additionally, we disclose the co-crystal structure of our inhibitor series bound to the human PRC2 complex.
Asunto(s)
Antineoplásicos/farmacología , Ensayos Clínicos Fase I como Asunto , Inhibidores Enzimáticos/farmacología , N-Metiltransferasa de Histona-Lisina/antagonistas & inhibidores , Indoles/farmacología , Linfoma de Células B/tratamiento farmacológico , Piperidinas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Histona Metiltransferasas , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Indoles/síntesis química , Indoles/química , Modelos Moleculares , Estructura Molecular , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Piperidinas/síntesis química , Piperidinas/química , Ratas , Relación Estructura-ActividadRESUMEN
This communication describes the identification and optimization of a series of pan-KDM5 inhibitors derived from compound 1, a hit initially identified against KDM4C. Compound 1 was optimized to afford compound 20, a 10nM inhibitor of KDM5A. Compound 20 is highly selective for the KDM5 enzymes versus other histone lysine demethylases and demonstrates activity in a cellular assay measuring the increase in global histone 3 lysine 4 tri-methylation (H3K4me3). In addition compound 20 has good ADME properties, excellent mouse PK, and is a suitable starting point for further optimization.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Proteína 2 de Unión a Retinoblastoma/antagonistas & inhibidores , Animales , Sitios de Unión , Western Blotting , Línea Celular , Descubrimiento de Drogas , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Humanos , Concentración 50 Inhibidora , Ratones , Microsomas Hepáticos/enzimología , Modelos Moleculares , RatasRESUMEN
Features from a high throughput screening (HTS) hit and a previously reported scaffold were combined to generate 1,7-naphthyridones as novel KDM5 enzyme inhibitors with nanomolar potencies. These molecules exhibited high selectivity over the related KDM4C and KDM2B isoforms. An X-ray co-crystal structure of a representative molecule bound to KDM5A showed that these inhibitors are competitive with the co-substrate (2-oxoglutarate or 2-OG).
Asunto(s)
Histona Demetilasas con Dominio de Jumonji/antagonistas & inhibidores , Naftiridinas/farmacología , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Represoras/antagonistas & inhibidores , Proteína 2 de Unión a Retinoblastoma/antagonistas & inhibidores , Animales , Cristalografía por Rayos X , Perros , Diseño de Fármacos , Humanos , Células de Riñón Canino Madin Darby , Naftiridinas/química , Relación Estructura-ActividadRESUMEN
Starting with a lead [1,5-a]pyrimidin-7(4H)-one-containing molecule (1), we generated potent, selective and orally bioavailable KDM5 inhibitors. Using structure- and property-based approaches, we designed 48 with improved cell potency (PC9 H3K4Me3 EC50=0.34µM). Furthermore, 48 maintained suitable physiochemical properties and displayed an excellent pharmacokinetic (PK) profile in mice. When dosed orally in mice at 50mg/kg twice a day (BID), 48 showed an unbound maximal plasma concentration (Cmax) >15-fold over its cell EC50, thereby providing a robust chemical probe for studying KDM5 biological functions in vivo.
Asunto(s)
Pirazoles/química , Pirimidinonas/química , Proteína 2 de Unión a Retinoblastoma/antagonistas & inhibidores , Administración Oral , Animales , Sitios de Unión , Cristalografía por Rayos X , Femenino , Semivida , Histonas/metabolismo , Humanos , Hígado/metabolismo , Ratones , Microsomas Hepáticos/metabolismo , Simulación de Dinámica Molecular , Pirazoles/síntesis química , Pirazoles/farmacocinética , Pirimidinonas/sangre , Pirimidinonas/síntesis química , Pirimidinonas/farmacocinética , Ratas , Proteína 2 de Unión a Retinoblastoma/metabolismo , Relación Estructura-ActividadRESUMEN
The MET receptor tyrosine kinase is involved in cell growth, survival, and invasion. Clinical studies with small molecule MET inhibitors have shown the role of biomarkers in identifying patients most likely to benefit from MET-targeted therapy. AMG 337 is an oral, small molecule, ATP-competitive, highly selective inhibitor of the MET receptor. Herein, we describe AMG 337 preclinical activity and mechanism of action in MET-dependent tumor models. These studies suggest MET is the only therapeutic target for AMG 337. In an unbiased tumor cell line proliferation screen (260 cell lines), a closely related analogue of AMG 337, Compound 5, exhibited activity in 2 of 260 cell lines; both were MET-amplified. Additional studies examining the effects of AMG 337 on the proliferation of a limited panel of cell lines with varying MET copy numbers revealed that high-level focal MET amplification (>12 copies) was required to confer MET oncogene addiction and AMG 337 sensitivity. One MET-amplified cell line, H1573 (>12 copies), was AMG 337 insensitive, possibly because of a downstream G12A KRAS mutation. Mechanism-of-action studies in sensitive MET-amplified cell lines demonstrated that AMG 337 inhibited MET and adaptor protein Gab-1 phosphorylation, subsequently blocking the downstream PI3K and MAPK pathways. AMG 337 exhibited potency in pharmacodynamic assays evaluating MET signaling in tumor xenograft models; >90% inhibition of Gab-1 phosphorylation was observed at 0.75 mg/kg. These findings describe the preclinical activity and mechanism of action of AMG 337 in MET-dependent tumor models and indicate its potential as a novel therapeutic for the treatment of MET-dependent tumors. Mol Cancer Ther; 15(7); 1568-79. ©2016 AACR.
Asunto(s)
Antineoplásicos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Animales , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Amplificación de Genes , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Necrosis , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The KDM5 family of histone demethylases catalyzes the demethylation of histone H3 on lysine 4 (H3K4) and is required for the survival of drug-tolerant persister cancer cells (DTPs). Here we report the discovery and characterization of the specific KDM5 inhibitor CPI-455. The crystal structure of KDM5A revealed the mechanism of inhibition of CPI-455 as well as the topological arrangements of protein domains that influence substrate binding. CPI-455 mediated KDM5 inhibition, elevated global levels of H3K4 trimethylation (H3K4me3) and decreased the number of DTPs in multiple cancer cell line models treated with standard chemotherapy or targeted agents. These findings show that pretreatment of cancer cells with a KDM5-specific inhibitor results in the ablation of a subpopulation of cancer cells that can serve as the founders for therapeutic relapse.
Asunto(s)
Antineoplásicos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Proteína 2 de Unión a Retinoblastoma/antagonistas & inhibidores , Antineoplásicos/química , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estructura Molecular , Proteína 2 de Unión a Retinoblastoma/metabolismo , Relación Estructura-ActividadRESUMEN
Covalent modification of histones is a fundamental mechanism of regulated gene expression in eukaryotes, and interpretation of histone modifications is an essential feature of epigenetic control. Bromodomains are specialized binding modules that interact with acetylated histones, linking chromatin recognition to gene transcription. Because of their ability to function in a domain-specific fashion, selective disruption of bromodomain:acetylated histone interactions with chemical probes serves as a powerful means for understanding biological processes regulated by these chromatin adaptors. Here we describe the discovery and characterization of potent and selective small molecule inhibitors for the bromodomains of CREBBP/EP300 that engage their target in cellular assays. We use these tools to demonstrate a critical role for CREBBP/EP300 bromodomains in regulatory T cell biology. Because regulatory T cell recruitment to tumors is a major mechanism of immune evasion by cancer cells, our data highlight the importance of CREBBP/EP300 bromodomain inhibition as a novel, small molecule-based approach for cancer immunotherapy.
Asunto(s)
Proteína de Unión a CREB/antagonistas & inhibidores , Proteína p300 Asociada a E1A/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Acetilación/efectos de los fármacos , Proteína de Unión a CREB/química , Proteína de Unión a CREB/metabolismo , Diferenciación Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , Proteína p300 Asociada a E1A/química , Proteína p300 Asociada a E1A/metabolismo , Factores de Transcripción Forkhead/metabolismo , Histonas/metabolismo , Humanos , Simulación del Acoplamiento Molecular , Estructura Terciaria de Proteína/efectos de los fármacos , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/metabolismo , Transcriptoma/efectos de los fármacosRESUMEN
Inhibition of the bromodomains of the BET family, of which BRD4 is a member, has been shown to decrease myc and interleukin (IL) 6 in vivo, markers that are of therapeutic relevance to cancer and inflammatory disease, respectively. Herein we report substituted benzo[b]isoxazolo[4,5-d]azepines and benzotriazolo[4,3-d][1,4]diazepines as fragment-derived novel inhibitors of the bromodomain of BRD4. Compounds from these series were potent and selective in cells, and subsequent optimization of microsomal stability yielded representatives that demonstrated dose- and time-dependent reduction of plasma IL-6 in mice.
RESUMEN
In recent years, inhibition of the interaction between the bromodomain and extra-terminal domain (BET) family of chromatin adaptors and acetyl-lysine residues on chromatin has emerged as a promising approach to regulate the expression of important disease-relevant genes, including MYC, BCL-2, and NF-κB. Here we describe the identification and characterization of a potent and selective benzoisoxazoloazepine BET bromodomain inhibitor that attenuates BET-dependent gene expression in vivo, demonstrates antitumor efficacy in an MV-4-11 mouse xenograft model, and is currently undergoing human clinical trials for hematological malignancies (CPI-0610).
Asunto(s)
Antineoplásicos/química , Antineoplásicos/uso terapéutico , Azepinas/química , Azepinas/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Proteínas Nucleares/antagonistas & inhibidores , Factores de Transcripción/antagonistas & inhibidores , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Azepinas/farmacocinética , Azepinas/farmacología , Proteínas de Ciclo Celular , Línea Celular Tumoral , Ensayos Clínicos como Asunto , Perros , Genes myc/efectos de los fármacos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Ratones , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Ratas , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Deregulation of the receptor tyrosine kinase mesenchymal epithelial transition factor (MET) has been implicated in several human cancers and is an attractive target for small molecule drug discovery. Herein, we report the discovery of compound 23 (AMG 337), which demonstrates nanomolar inhibition of MET kinase activity, desirable preclinical pharmacokinetics, significant inhibition of MET phosphorylation in mice, and robust tumor growth inhibition in a MET-dependent mouse efficacy model.
Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Piridonas/síntesis química , Piridonas/farmacología , Triazoles/síntesis química , Triazoles/farmacología , Animales , Antineoplásicos/farmacocinética , Cristalografía por Rayos X , Diseño de Fármacos , Descubrimiento de Drogas , Humanos , Ratones , Modelos Moleculares , Piridonas/farmacocinética , Relación Estructura-Actividad , Triazoles/farmacocinética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The discovery and optimization of a series of small molecule EZH2 inhibitors is described. Starting from dimethylpyridone HTS hit (2), a series of indole-based EZH2 inhibitors were identified. Biochemical potency and microsomal stability were optimized during these studies and afforded compound 22. This compound demonstrates nanomolar levels of biochemical potency (IC50=0.002 µM), cellular potency (EC50=0.080 µM), and afforded tumor regression when dosed (200 mpk SC BID) in an EZH2 dependent tumor xenograft model.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Indoles/química , Complejo Represivo Polycomb 2/antagonistas & inhibidores , Animales , Antineoplásicos/síntesis química , Línea Celular Tumoral , Técnicas de Química Sintética , Diseño de Fármacos , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Estabilidad de Medicamentos , Proteína Potenciadora del Homólogo Zeste 2 , Células HeLa/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Ratones , Terapia Molecular Dirigida/métodos , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
In this report we detail the evolution of our previously reported thiophene isoxazole BET inhibitor chemotype exemplified by CPI-3 to a novel bromodomain selective chemotype (the methyl isoxazoleazepine chemotype) exemplified by carboxamide 23. The methyl isoxazoleazepine chemotype provides potent inhibition of the bromodomains of the BET family, excellent in vivo PK across species, low unbound clearance, and target engagement in a MYC PK-PD model.
Asunto(s)
Azepinas/farmacología , Diseño de Fármacos , Proteínas Nucleares/antagonistas & inhibidores , Oxazoles/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas de Unión al ARN/antagonistas & inhibidores , Factores de Transcripción/antagonistas & inhibidores , Azepinas/síntesis química , Azepinas/química , Proteínas de Ciclo Celular , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Oxazoles/síntesis química , Oxazoles/química , Relación Estructura-ActividadRESUMEN
The overexpression of c-Met and/or hepatocyte growth factor (HGF), the amplification of the MET gene, and mutations in the c-Met kinase domain can activate signaling pathways that contribute to cancer progression by enabling tumor cell proliferation, survival, invasion, and metastasis. Herein, we report the discovery of 8-fluorotriazolopyridines as inhibitors of c-Met activity. Optimization of the 8-fluorotriazolopyridine scaffold through the combination of structure-based drug design, SAR studies, and metabolite identification provided potent (cellular IC50 < 10 nM), selective inhibitors of c-Met with desirable pharmacokinetic properties that demonstrate potent inhibition of HGF-mediated c-Met phosphorylation in a mouse liver pharmacodynamic model.