RESUMO
The growing opportunities recognized for covalent drug inhibitors, like KRAS G12C inhibitors, are driving the need for mass spectrometry methods that can quickly and robustly measure therapeutic drug activity in vivo for drug discovery research and development. Effective front-end sample preparation is critical for proteins extracted from tumors but is generally labor intensive and impractical for large sample numbers typical in pharmacodynamic (PD) studies. Herein, we describe an automated and integrated sample preparation method for the measurement of activity levels of KRAS G12C drug inhibitor alkylation from complex tumor samples involving high throughput detergent removal and preconcentration followed by quantitation using mass spectrometry. We introduce a robust assay with an average intra-assay coefficient of variation (CV) of 4% and an interassay CV of 6% obtained from seven studies, enabling us to understand the relationship between KRAS G12C target occupancy and the therapeutic PD effect from mouse tumor samples. Further, the data demonstrated that the drug candidate GDC-6036, a KRAS G12C covalent inhibitor, shows dose-dependent target inhibition (KRAS G12C alkylation) and MAPK pathway inhibition, which correlate with high antitumor potency in the MIA PaCa-2 pancreatic xenograft model.
Assuntos
Antineoplásicos , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Animais , Camundongos , Proteínas Proto-Oncogênicas p21(ras)/genética , Linhagem Celular Tumoral , Mutação , Antineoplásicos/farmacologia , Modelos Animais de DoençasRESUMO
The treatment of epidermal growth factor receptor (EGFR)-driven non-small cell lung cancers with the T790M resistance mutation remains a significant unmet medical need. We report the identification of 4-aminoindazolyl-dihydrofuro[3,4-d]pyrimidines as non-covalent inhibitors of EGFR, with excellent activity against the T790M resistance double mutants and initial single activating mutants. Using an optimization strategy focused on structure-based design and improving PK properties through metabolite identification, we obtained advanced leads with high oral exposure.
Assuntos
Receptores ErbB/antagonistas & inibidores , Furanos/farmacologia , Indazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Animais , Sítios de Ligação , Cristalografia por Raios X , Cães , Receptores ErbB/química , Cloridrato de Erlotinib/farmacologia , Furanos/síntese química , Furanos/química , Furanos/farmacocinética , Hepatócitos/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Ligação de Hidrogênio , Indazóis/síntese química , Indazóis/química , Indazóis/farmacocinética , Camundongos , Microssomos Hepáticos/metabolismo , Mutação Puntual , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/síntese química , Pirimidinas/química , Pirimidinas/farmacocinética , RatosRESUMO
A series of 4-azaindole-containing p21-activated kinase-1 (PAK1) inhibitors was prepared with the goal of improving physicochemical properties relative to an indole starting point. Indole 1 represented an attractive, non-basic scaffold with good PAK1 affinity and cellular potency but was compromised by high lipophilicity (clogD=4.4). Azaindole 5 was designed as an indole surrogate with the goal of lowering logD and resulted in equipotent PAK1 inhibition with a 2-fold improvement in cellular potency over 1. Structure-activity relationship studies around 5 identified additional 4-azaindole analogs with superior PAK1 biochemical activity (Ki <10nM) and up to 24-fold selectivity for group I over group II PAKs. Compounds from this series showed enhanced permeability, improved aqueous solubility, and lower plasma protein binding over indole 1. The improvement in physicochemical properties translated to a 20-fold decrease in unbound clearance in mouse PK studies for azaindole 5 relative to indole 1.
Assuntos
Indóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinases Ativadas por p21/antagonistas & inibidores , Animais , Cães , Relação Dose-Resposta a Droga , Humanos , Indóis/síntese química , Indóis/química , Células Madin Darby de Rim Canino , Camundongos , Camundongos Nus , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Quinases Ativadas por p21/metabolismoRESUMO
Modification of the δ-sultam ring of RORc inverse agonist 2 led to the discovery of more polar oxa-sultam 65. The less lipophilic inverse agonist (65) displayed high potency in a biochemical assay, which translated into inhibition of IL-17 production in human peripheral blood mononuclear cells. The successful reduction of lipophilicity of this new analog gave rise to additional improvements in ROR selectivity and aqueous kinetic solubility, as well as reduction in plasma protein binding, while maintaining high cellular permeability.
Assuntos
Lipídeos/química , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Descoberta de Drogas , Agonismo Inverso de Drogas , Naftalenossulfonatos/químicaRESUMO
A high-throughput screen of the Genentech/Roche compound collection using a retinoic acid receptor-related orphan receptor C (RORc, RORγ, or NR1F3) biochemical assay revealed a N-sulfonyl-tetrahydroquinoline hit. Herein, we describe the hit-to-lead optimization and structure-activity relationships of these tetrahydroquinoline RORc inverse agonists. Through iterative synthesis and analog design, we identified compounds with improved biochemical RORc inverse agonist activity and RORc cellular potencies. These improved N-sulfonyl-tetrahydroquinoline compounds also exhibited selectivity for RORc over other nuclear receptors.
Assuntos
Agonismo Inverso de Drogas , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Quinolinas/farmacologia , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Quinolinas/síntese química , Quinolinas/química , Relação Estrutura-AtividadeRESUMO
The nuclear receptor (NR) retinoic acid receptor-related orphan receptor gamma (RORγ, RORc, or NR1F3) is a promising target for the treatment of autoimmune diseases. RORc is a critical regulator in the production of the pro-inflammatory cytokine interleukin-17. We discovered a series of potent and selective imidazo[1,5-a]pyridine and -pyrimidine RORc inverse agonists. The most potent compounds displayed >300-fold selectivity for RORc over the other ROR family members, PPARγ, and NRs in our cellular selectivity panel. The favorable potency, selectivity, and physiochemical properties of GNE-0946 (9) and GNE-6468 (28), in addition to their potent suppression of IL-17 production in human primary cells, support their use as chemical biology tools to further explore the role of RORc in human biology.
Assuntos
Imidazóis/química , Imidazóis/farmacologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Piridinas/química , Piridinas/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Animais , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Linhagem Celular , Células Cultivadas , Descoberta de Drogas , Células HEK293 , Humanos , Imidazóis/metabolismo , Imidazóis/farmacocinética , Interleucina-17/imunologia , Fígado/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Piridinas/metabolismo , Piridinas/farmacocinética , Pirimidinas/metabolismo , Pirimidinas/farmacocinética , Ratos , Relação Estrutura-AtividadeRESUMO
Using structure-based drug design principles, we identified opportunities to reduce the lipophilicity of our tertiary sulfonamide RORc inverse agonists. The new analogs possessed improved RORc cellular potencies with >77-fold selectivity for RORc over other nuclear receptors in our cell assay suite. The reduction in lipophilicity also led to an increased plasma-protein unbound fraction and improvements in cellular permeability and aqueous solubility.
Assuntos
Proteínas Sanguíneas/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Sulfonamidas/farmacologia , Animais , Sítios de Ligação/efeitos dos fármacos , Proteínas Sanguíneas/metabolismo , Cristalografia por Raios X , Cães , Relação Dose-Resposta a Droga , Desenho de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células Madin Darby de Rim Canino , Modelos Moleculares , Estrutura Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Ratos , Solubilidade , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/químicaRESUMO
The identification of a new series of RORc inverse agonists is described. Comprehensive structure-activity relationship studies of this reversed sulfonamide series identified potent RORc inverse agonists in biochemical and cellular assays which were also selective against a panel of nuclear receptors. Our work has contributed a compound that may serve as a useful in vitro tool to delineate the complex biological pathways involved in signalling through RORc. An X-ray co-crystal structure of an analogue with RORc has also provided useful insights into the binding interactions of the new series.
Assuntos
Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Sulfonamidas/química , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Citocinas/biossíntese , Agonismo Inverso de Drogas , Células HEK293 , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Simulação de Dinâmica Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/toxicidadeRESUMO
Transient receptor potential ankyrin 1 (TRPA1) is a nonselective calcium ion channel highly expressed in the primary sensory neurons, functioning as a polymodal sensor for exogenous and endogenous stimuli, and has been implicated in neuropathic pain and respiratory disease. Herein, we describe the optimization of potent, selective, and orally bioavailable TRPA1 small molecule antagonists with strong in vivo target engagement in rodent models. Several lead molecules in preclinical single- and short-term repeat-dose toxicity studies exhibited profound prolongation of coagulation parameters. Based on a thorough investigative toxicology and clinical pathology analysis, anticoagulation effects in vivo are hypothesized to be manifested by a metaboliteâgenerated by aldehyde oxidase (AO)âpossessing a similar pharmacophore to known anticoagulants (i.e., coumarins, indandiones). Further optimization to block AO-mediated metabolism yielded compounds that ameliorated coagulation effects in vivo, resulting in the discovery and advancement of clinical candidate GDC-6599, currently in Phase II clinical trials for respiratory indications.
Assuntos
Doenças Respiratórias , Canais de Potencial de Receptor Transitório , Humanos , Canais de Potencial de Receptor Transitório/metabolismo , Canal de Cátion TRPA1 , Aldeído Oxidase/metabolismo , Oxirredutases/metabolismo , Proteínas do Citoesqueleto/metabolismoRESUMO
The application of modeling and simulation techniques is increasingly common in the preclinical stages of the drug development process. GDC-0917 [(S)-1-((S)-2-cyclohexyl-2-((S)-2-(methylamino)propanamido)acetyl)-N-(2-(oxazol-2-yl)-4-phenylthiazol-5-yl)pyrrolidine-2-carboxamide] is a potent second-generation antagonist of inhibitor of apoptosis (IAP) proteins that is being developed for the treatment of various cancers. GDC-0917 has low to moderate clearance in the mouse (12.0 ml/min/kg), rat (27.0 ml/min/kg), and dog (15.3 ml/min/kg), and high clearance in the monkey (67.6 ml/min/kg). Accordingly, oral bioavailability was lowest in monkeys compared with other species. Based on our experience with a prototype molecule with similar structure, in vitro-in vivo extrapolation was used to predict a moderate clearance (11.5 ml/min/kg) in humans. The predicted human volume of distribution was estimated using simple allometry at 6.69 l/kg. Translational pharmacokinetic-pharmacodynamic (PK-PD) analysis using results from MDA-MB-231-X1.1 breast cancer xenograft studies and predicted human pharmacokinetics suggests that ED50 and ED90 targets can be achieved in humans using acceptable doses (72 mg and 660 mg, respectively) and under an acceptable time frame. The relationship between GDC-0917 concentrations and pharmacodynamic response (cIAP1 degradation) was characterized using an in vitro peripheral blood mononuclear cell immunoassay. Simulations of human GDC-0917 plasma concentration-time profile and cIAP1 degradation at the 5-mg starting dose in the phase 1 clinical trial agreed well with observations. This work shows the importance of leveraging information from prototype molecules and illustrates how modeling and simulation can be used to add value to preclinical studies in the early stages of the drug development process.
Assuntos
Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Proteínas Inibidoras de Apoptose/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/farmacocinética , Animais , Disponibilidade Biológica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Cães , Avaliação Pré-Clínica de Medicamentos , Feminino , Meia-Vida , Hepatócitos/efeitos dos fármacos , Humanos , Macaca fascicularis , Masculino , Camundongos , Camundongos SCID , Ratos , Ratos Sprague-Dawley , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
In the early drug discovery environment, poorly soluble compounds with suboptimal potency are often used in efficacy studies to demonstrate in vivo preclinical proof-of-concept for new drug discovery targets and in preclinical toxicity studies to assess chemical scaffold safety. These compounds present a challenge to formulation scientists who are tasked with improving their oral bioavailability because high systemic concentrations are required. Despite the use of enabling formulations, increases in systemic exposure following oral delivery are often not achieved. We hypothesize that in some cases non-sink intestinal permeation can occur for poorly soluble compounds where their high systemic concentrations can act to inhibit their own oral absorption. Rats were given a 30 mg/kg oral dose of 1,3-dicyclohexyl urea (DCU) alone or concurrently with deuterated DCU (D8-DCU) intravenous infusions at rates of 13, 17, and 22 mg/kg/h. D8-DCU infusions dose dependently inhibited DCU oral absorption up to a maximum of 92%. Physiologically based pharmacokinetic modeling was utilized to understand the complex interaction between high DCU systemic concentrations and its effect on its own oral absorption. We show that high systemic concentrations of DCU act to suppress its own absorption by creating a condition where intestinal permeation occurs under non-sink conditions. More importantly, we identify relevant DCU concentrations that create the concentration gradient driving the intestinal permeation process. A new parameter, the maximum permeation extraction ratio, is proposed and provides a simple means to assess the extent of non-sink permeation.
Assuntos
Química Farmacêutica/métodos , Administração Oral , Animais , Masculino , Modelos Teóricos , Ratos , Ratos Sprague-Dawley , Solubilidade , Ureia/administração & dosagem , Ureia/análogos & derivados , Ureia/farmacocinéticaRESUMO
In recent years, one of the biggest challenges for pharmaceutical industry is to increase the speed of finding new medicines while at the same time controlling the ever rising cost of drug discovery and development. In order to increase the speed at which drug candidates are identified, high throughput assays (HTS) have been developed and have been widely implemented in the pharmaceutical industry. Cassette (or N-in-1) dosing for pharmacokinetic (PK) evaluation is the process of generating in vivo PK data in a higher throughput manner by dosing multiple compounds to individual animals. However, due to generally poor solubility of compounds being tested, high percentages of organic solvents are often used in the formulation vehicle in order to solubilize compounds for cassette studies. Utilization of high organic content in formulation vehicles can result in unwanted side effects and animal tolerability issues. The current study evaluates the suitability of using nanoparticles in an aqueous suspension for cassette IV dosing. Nanoparticles of 10 poorly soluble marketed drugs covering a wide range of clearances were prepared using an electrospray device and evaluated. PXRD, TGA and particle size data were obtained in order to ensure the quality for in vivo evaluation. Phosphate buffered saline (PBS) was used as the vehicle in IV cassette study using nanoparticles and pharmacokinetic estimates from this study were comparable to those from a traditional high organic formulation approach. The use of nanoparticles in an aqueous suspension formulation was demonstrated to be appropriate for cassette dosing.
Assuntos
Nanopartículas , Farmacocinética , Animais , Cromatografia Líquida , Injeções Intravenosas , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Solubilidade , Espectrometria de Massas em Tandem , Termogravimetria , Difração de Raios XRESUMO
(R)-N-(3-(6-(4-(1,4-dimethyl-3-oxopiperazin-2-yl)phenylamino)-4-methyl-5-oxo-4,5-dihydropyrazin-2-yl)-2-methylphenyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxamide (GDC-0834) is a potent and selective inhibitor of Bruton's tyrosine kinase (BTK), investigated as a potential treatment for rheumatoid arthritis. In vitro metabolite identification studies in hepatocytes revealed predominant formation of an inactive metabolite (M1) via amide hydrolysis in human. The formation of M1 appeared to be NADPH-independent in human liver microsomes. M1 was found in only minor to moderate quantities in plasma from preclinical species dosed with GDC-0834. Human clearance predictions using various methodologies resulted in estimates ranging from low to high. In addition, GDC-0834 exhibited low clearance in PXB chimeric mice with humanized liver. Uncertainty in human pharmacokinetic prediction and high interest in a BTK inhibitor for clinical evaluation prompted an investigational new drug strategy, in which GDC-0834 was rapidly advanced to a single-dose human clinical trial. GDC-0834 plasma concentrations in humans were below the limit of quantitation (<1 ng/ml) in most samples from the cohorts dosed orally at 35 and 105 mg. In contrast, substantial plasma concentrations of M1 were observed. In human plasma and urine, only M1 and its sequential metabolites were identified. The formation kinetics of M1 was evaluated in rat, dog, monkey, and human liver microsomes in the absence of NADPH. The maximum rate of M1 formation (V(max)) was substantially higher in human compared with that in other species. In contrast, the Michaelis-Menten constant (K(m)) was comparable among species. Intrinsic clearance (V(max)/K(m)) of GDC-0834 from M1 formation in human was 23- to 169-fold higher than observed in rat, dog, and monkey.
Assuntos
Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinonas/metabolismo , Pirimidinonas/farmacocinética , Tiofenos/metabolismo , Tiofenos/farmacocinética , Tirosina Quinase da Agamaglobulinemia , Amidas/metabolismo , Animais , Células Cultivadas , Ensaios Clínicos Fase I como Assunto , Cães , Método Duplo-Cego , Feminino , Hepatócitos/metabolismo , Humanos , Hidrólise , Macaca fascicularis , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Proteínas Tirosina Quinases/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Ratos , Ratos Sprague-Dawley , Especificidade da EspécieRESUMO
Optimization of a series of aryl urea RAF inhibitors led to the identification of type II pan-RAF inhibitor GNE-0749 (7), which features a fluoroquinazolinone hinge-binding motif. By minimizing reliance on common polar hinge contacts, this hinge binder allows for a greater contribution of RAF-specific residue interactions, resulting in exquisite kinase selectivity. Strategic substitution of fluorine at the C5 position efficiently masked the adjacent polar NH functionality and increased solubility by impeding a solid-state conformation associated with stronger crystal packing of the molecule. The resulting improvements in permeability and solubility enabled oral dosing of 7. In vivo evaluation of 7 in combination with the MEK inhibitor cobimetinib demonstrated synergistic pathway inhibition and significant tumor growth inhibition in a KRAS mutant xenograft mouse model.
Assuntos
Neoplasias/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinonas/uso terapêutico , Quinases raf/antagonistas & inibidores , Animais , Azetidinas/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Cães , Combinação de Medicamentos , Sinergismo Farmacológico , Feminino , Humanos , Células Madin Darby de Rim Canino , Camundongos Nus , Estrutura Molecular , Mutação , Compostos de Fenilureia/química , Compostos de Fenilureia/metabolismo , Piperidinas/uso terapêutico , Ligação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Quinazolinonas/química , Quinazolinonas/metabolismo , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases raf/genética , Quinases raf/metabolismoRESUMO
Structure-based optimization of a set of aryl urea RAF inhibitors has led to the identification of Type II pan-RAF inhibitor GNE-9815 (7), which features a unique pyrido[2,3-d]pyridazin-8(7H)-one hinge-binding motif. With minimal polar hinge contacts, the pyridopyridazinone hinge binder moiety affords exquisite kinase selectivity in a lipophilic efficient manner. The improved physicochemical properties of GNE-9815 provided a path for oral dosing without enabling formulations. In vivo evaluation of GNE-9815 in combination with the MEK inhibitor cobimetinib demonstrated synergistic MAPK pathway modulation in an HCT116 xenograft mouse model. To the best of our knowledge, GNE-9815 is among the most highly kinase-selective RAF inhibitors reported to date.
RESUMO
Transient receptor potential ankyrin 1 (TRPA1) is a nonselective calcium-permeable ion channel highly expressed in the primary sensory neurons functioning as a polymodal sensor for exogenous and endogenous stimuli and has generated widespread interest as a target for inhibition due to its implication in neuropathic pain and respiratory disease. Herein, we describe the optimization of a series of potent, selective, and orally bioavailable TRPA1 small molecule antagonists, leading to the discovery of a novel tetrahydrofuran-based linker. Given the balance of physicochemical properties and strong in vivo target engagement in a rat AITC-induced pain assay, compound 20 was progressed into a guinea pig ovalbumin asthma model where it exhibited significant dose-dependent reduction of inflammatory response. Furthermore, the structure of the TRPA1 channel bound to compound 21 was determined via cryogenic electron microscopy to a resolution of 3 Å, revealing the binding site and mechanism of action for this class of antagonists.
Assuntos
Asma/tratamento farmacológico , Furanos/uso terapêutico , Purinas/uso terapêutico , Canal de Cátion TRPA1/antagonistas & inibidores , Animais , Asma/induzido quimicamente , Asma/complicações , Células CHO , Cricetulus , Furanos/síntese química , Furanos/metabolismo , Cobaias , Humanos , Inflamação/tratamento farmacológico , Inflamação/etiologia , Ligantes , Masculino , Estrutura Molecular , Ovalbumina , Oxidiazóis/síntese química , Oxidiazóis/metabolismo , Oxidiazóis/uso terapêutico , Ligação Proteica , Purinas/síntese química , Purinas/metabolismo , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Canal de Cátion TRPA1/metabolismoRESUMO
Factors determining the pharmacokinetics of 2-chloro-N-(4-chloro-3-(pyridine-2-yl)phenyl)-4-(methylsulfonyl)benzamide (GDC-0449) were investigated using preclinical studies and physiologically based pharmacokinetic (PBPK) modeling. Multiple-dose studies where dogs were given twice-daily oral doses of either 7.5 or 25 mg/kg GDC-0449 showed less than dose-proportional increases in exposure on day 1. At steady state, exposures were comparable between the two dose groups. Oral administration of activated charcoal to dogs receiving oral or intravenous GDC-0449 (25 mg) showed a more rapid decrease in plasma concentrations, suggesting that the concentration gradient driving intestinal membrane permeation was reversible. The biliary clearance of GDC-0449 in dogs was low (0.04 ml/min/kg) and did not account for the majority of the estimated systemic clearance (approximately 19% of systemic clearance). Likewise, in vitro studies using sandwich-cultured human hepatocytes showed negligible biliary excretion. The effect of particle size on oral absorption was shown in a single-dose study where 150 mg of GDC-0449 of two particle sizes was administered. An oral PBPK model was used to investigate mechanisms determining the oral pharmacokinetics of GDC-0449. The overall oral absorption of GDC-0449 appears to depend on the interplay between the dissolution and intestinal membrane permeation processes. A unique feature of GDC-0449 distinguishing it from other Biopharmaceutical Classification System II compounds was that incorporation of the effects of solubility rate-limited absorption and nonsink permeation on the intestinal membrane permeation process was necessary to describe its pharmacokinetic behavior.
Assuntos
Anilidas/química , Anilidas/farmacocinética , Proteínas Hedgehog/antagonistas & inibidores , Piridinas/química , Piridinas/farmacocinética , Administração Oral , Anilidas/administração & dosagem , Animais , Carvão Vegetal/farmacologia , Simulação por Computador , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Interações Medicamentosas , Hepatócitos/metabolismo , Humanos , Injeções Intravenosas , Absorção Intestinal , Masculino , Tamanho da Partícula , Piridinas/administração & dosagem , SolubilidadeRESUMO
A class of imidazoisoindole (III) heme-binding indoleamine-2,3-dioxygenase (IDO1) inhibitors were optimized via structure-based drug design into a series of tryptophan-2,3-dioxygenase (TDO)-selective inhibitors. Kynurenine pathway modulation was demonstrated in vivo, which enabled evaluation of TDO as a potential cancer immunotherapy target. As means of mitigating the risk of drug-drug interactions arising from cytochrome P450 inhibition, a novel property-based drug design parameter, herein referred to as the CYP Index, was implemented for the design of inhibitors with appreciable selectivity for TDO over CYP3A4. We anticipate the CYP Index will be a valuable design parameter for optimizing CYP inhibition of any small molecule inhibitor containing a Lewis basic motif capable of binding heme.
RESUMO
SAR for a wide variety of heterocyclic replacements for a benzimidazole led to the discovery of functionalized 2-pyridyl amides as novel inhibitors of the hedgehog pathway. The 2-pyridyl amides were optimized for potency, PK, and drug-like properties by modifications to the amide portion of the molecule resulting in 31 (GDC-0449). Amide 31 produced complete tumor regression at doses as low as 12.5mg/kg BID in a medulloblastoma allograft mouse model that is wholly dependent on the Hh pathway for growth and is currently in human clinical trials, where it is initially being evaluated for the treatment of BCC.
Assuntos
Amidas/química , Anilidas/química , Proteínas Hedgehog/metabolismo , Piridinas/química , Amidas/síntese química , Amidas/farmacologia , Anilidas/síntese química , Anilidas/farmacologia , Animais , Benzimidazóis/química , Carcinoma Basocelular/tratamento farmacológico , Linhagem Celular , Neoplasias Cerebelares/tratamento farmacológico , Proteínas Hedgehog/antagonistas & inibidores , Humanos , Meduloblastoma/tratamento farmacológico , Camundongos , Camundongos Nus , Piridinas/síntese química , Piridinas/farmacologia , Transdução de Sinais , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Solubilization of new chemical entities for toxicity assessment must use excipients that do not negatively impact drug pharmacokinetics and toxicology. In this study, we investigated the tolerability of a model freebase compound, GDC-0152, solubilized by pH adjustment with succinic acid and complexation with hydroxypropyl-ß-cyclodextrin (HP-ß-CD) to enable intravenous use. Solubility, critical micelle concentration, and association constant with HP-ß-CD were determined. Blood compatibility and potential for hemolysis were assessed in vitro. Local tolerability was assessed after intravenous and subcutaneous injections in rats. A pharmacokinetic study was conducted in rats after intravenous bolus administration. GDC-0152 exhibited pH-dependent solubility that was influenced by self-association. The presence of succinic acid increased solubility in a concentration-dependent manner. HP-ß-CD alone also increased solubility, but the extent of solubility enhancement was significantly lower than succinic acid alone. Inclusion of HP-ß-CD in the solution of GDC-0152 improved blood compatibility, reduced hemolytic potential by â¼20-fold in vitro, and increased the maximum tolerated dose to 80 mg/kg.