RESUMEN
We describe the synthesis of triazole-containing carboline derivatives and their utility as bromodomain and extra-terminal (BET) inhibitors. A convergent synthetic route permitted the detailed investigation of deuteration and fluorination strategies to reduce clearance while maintaining a favorable in vitro profile. This work led to the identification of a potent BET inhibitor, 2-{8-fluoro-3-[4-(2H3)methyl-1-methyl-1H-1,2,3-triazol-5-yl]-5-[(S)-(oxan-4-yl)(phenyl)methyl]-5H-pyrido[3,2-b]indol-7-yl}propan-2-ol (15), which demonstrated reduced clearance and an improved pharmacokinetic (PK) profile across preclinical species. Importantly, no major metabolite was observed when 15 was incubated with human hepatocytes (hHEP) for 2 h. This study culminated with the evaluation of 15 in a mouse triple-negative breast cancer (TNBC) tumor model where it demonstrated robust efficacy at low doses.
RESUMEN
Inhibition of the bromodomain and extra-terminal (BET) family of adaptor proteins is an attractive strategy for targeting transcriptional regulation of key oncogenes, such as c-MYC. Starting with the screening hit 1, a combination of structure-activity relationship and protein structure-guided drug design led to the discovery of a differently oriented carbazole 9 with favorable binding to the tryptophan, proline, and phenylalanine (WPF) shelf conserved in the BET family. Identification of an additional lipophilic pocket and functional group optimization to optimize pharmacokinetic (PK) properties culminated in the discovery of 18 (BMS-986158) with excellent potency in binding and functional assays. On the basis of its favorable PK profile and robust in vivo activity in a panel of hematologic and solid tumor models, BMS-986158 was selected as a candidate for clinical evaluation.
Asunto(s)
Antineoplásicos/farmacología , Carbazoles/farmacología , Descubrimiento de Drogas , Fenilalanina/farmacología , Prolina/farmacología , Triptófano/farmacología , Administración Oral , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Carbazoles/administración & dosificación , Carbazoles/química , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Fenilalanina/administración & dosificación , Fenilalanina/química , Prolina/administración & dosificación , Prolina/química , Relación Estructura-Actividad , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Triptófano/administración & dosificación , Triptófano/químicaRESUMEN
We describe our efforts to introduce structural diversity to a previously described triazole-containing N1-carboline series of bromodomain and extra-terminal (BET) inhibitors. N9 carbolines were designed to retain favorable binding interactions that the N1-carbolines possess. A convergent synthetic route enabled modifications to reduce clearance, enhance physicochemical properties, and improve the overall in vitro profile. This work led to the identification of a potent BET inhibitor, (S)-2-{8-fluoro-5-[(3-fluoropyridin-2-yl)(oxan-4-yl)methyl]-7-[4-(2H3)methyl-1-methyl-1H-1,2,3-triazol-5-yl]-5H-pyrido[3,2-b]indol-3-yl}propan-2-ol (10), a compound with enhanced oral exposure in mice. Subsequent evaluation in a mouse triple-negative breast cancer tumor model revealed efficacy at 4 mg/kg of N9-carboline 10.
Asunto(s)
Antineoplásicos/farmacología , Carbolinas/farmacología , Desarrollo de Medicamentos , Proteínas/antagonistas & inhibidores , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Carbolinas/administración & dosificación , Carbolinas/química , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/patología , Ratones , Estructura Molecular , Proteínas/metabolismo , Relación Estructura-Actividad , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
We describe our efforts to identify structurally diverse leads in the triazole-containing N1-carboline series of bromodomain and extra-terminal inhibitors. Replacement of the N5 "cap" phenyl moiety with various heteroaryls, coupled with additional modifications to the carboline core, provided analogs with similar potency, improved pharmacokinetic properties, and increased solubility compared to our backup lead, BMS-986225 (2). Rapid SAR exploration was enabled by a convergent, synthetic route. These efforts provided a potent BET inhibitor, 3-fluoropyridyl 12, that demonstrated robust efficacy in a multiple myeloma mouse tumor model at 1 mg/kg.
Asunto(s)
Antineoplásicos/farmacología , Carbolinas/farmacología , Desarrollo de Medicamentos , Mieloma Múltiple/dietoterapia , Proteínas/antagonistas & inhibidores , Triazoles/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Carbolinas/síntesis química , Carbolinas/química , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Estructura Molecular , Mieloma Múltiple/metabolismo , Proteínas/metabolismo , Relación Estructura-Actividad , Triazoles/síntesis química , Triazoles/químicaRESUMEN
While the discovery of immune checkpoint inhibitors has led to robust, durable responses in a range of cancers, many patients do not respond to currently available therapeutics. Therefore, an urgent need exists to identify alternative mechanisms to augment the immune-mediated clearance of tumors. Hematopoetic progenitor kinase 1 (HPK1) is a serine-threonine kinase that acts as a negative regulator of T-cell receptor (TCR) signaling, to dampen the immune response. Herein we describe the structure-based discovery of isofuranones as inhibitors of HPK1. Optimization of the chemotype led to improvements in potency, selectivity, plasma protein binding, and metabolic stability, culminating in the identification of compound 24. Oral administration of 24, in combination with an anti-PD1 antibody, demonstrated robust enhancement of anti-PD1 efficacy in a syngeneic tumor model of colorectal cancer.
RESUMEN
Hematopoietic progenitor kinase 1 (HPK1) is an intracellular kinase that plays an important role in modulating tumor immune response and thus is an attractive target for drug discovery. Crystallization of the wild-type HPK1 kinase domain has been hampered by poor expression in recombinant systems and poor solubility. In this study, yeast surface display was applied to a library of HPK1 kinase-domain variants in order to select variants with an improved expression level and solubility. The HPK1 variant with the most improved properties contained two mutations, crystallized readily in complex with several small-molecule inhibitors and provided valuable insight to guide structure-based drug design. This work exemplifies the benefit of yeast surface display towards engineering crystallizable proteins and thus enabling structure-based drug discovery.
Asunto(s)
Ingeniería de Proteínas/métodos , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/genética , Técnicas de Visualización de Superficie Celular , Cristalización , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Mutagénesis , Mutación , Dominios Proteicos , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genéticaRESUMEN
Scaffold hopping and structure-based drug design were employed to identify substituted 4-aminoquinolines and 4-aminonaphthyridines as potent, small molecule inhibitors of tumor necrosis factor alpha (TNFα). Structure-activity relationships in both the quinoline and naphthyridine series leading to the identification of compound 42 with excellent potency and pharmacokinetic profile are discussed. X-ray co-crystal structure analysis and ultracentrifugation experiments clearly demonstrate that these inhibitors distort the TNFα trimer upon binding, leading to aberrant signaling when the trimer binds to TNF receptor 1 (TNFR1). Pharmacokinetic-pharmacodynamic activity of compound 42 in a TNF-induced IL-6 mouse model and in vivo activity in a collagen antibody-induced arthritis model, where it showed biologic-like in vivo efficacy, will be discussed.
Asunto(s)
Naftiridinas/farmacología , Quinolinas/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Reumatoide/tratamiento farmacológico , Diseño de Fármacos , Femenino , Humanos , Ratones Endogámicos C57BL , Microsomas Hepáticos/metabolismo , Estructura Molecular , Naftiridinas/síntesis química , Naftiridinas/farmacocinética , Naftiridinas/uso terapéutico , Prueba de Estudio Conceptual , Quinolinas/síntesis química , Quinolinas/farmacocinética , Quinolinas/uso terapéutico , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Novel imidazole-based TGFßR1 inhibitors were identified and optimized for potency, selectivity, and pharmacokinetic and physicochemical characteristics. Herein, we report the discovery, optimization, and evaluation of a potent, selective, and orally bioavailable TGFßR1 inhibitor, 10 (BMS-986260). This compound demonstrated functional activity in multiple TGFß-dependent cellular assays, excellent kinome selectivity, favorable pharmacokinetic properties, and curative in vivo efficacy in combination with anti-PD-1 antibody in murine colorectal cancer (CRC) models. Since daily dosing of TGFßR1 inhibitors is known to cause class-based cardiovascular (CV) toxicities in preclinical species, a dosing holiday schedule in the anti-PD-1 combination efficacy studies was explored. An intermittent dosing regimen of 3 days on and 4 days off allowed mitigation of CV toxicities in one month dog and rat toxicology studies and also provided similar efficacy as once daily dosing.
RESUMEN
The multifunctional cytokine TGFß plays a central role in regulating antitumor immunity. It has been postulated that inhibition of TGFß signaling in concert with checkpoint blockade will provide improved and durable immune response against tumors. Herein, we describe a novel series of 4-azaindole TGFß receptor kinase inhibitors with excellent selectivity for TGFß receptor 1 kinase. The combination of compound 3f and an antimouse-PD-1 antibody demonstrated significantly improved antitumor efficacy compared to either treatment alone in a murine tumor model.
RESUMEN
The TGFß-TGFßR signaling pathway has been reported to play a protective role in the later stages of tumorigenesis via increasing immunosuppressive Treg cells and facilitating the epithelial to mesenchymal transition (EMT). Therefore, inhibition of TGFßR has the potential to enhance antitumor immunity. Herein we disclose the identification and optimization of novel heterobicyclic inhibitors of TGFßRI that demonstrate potent inhibition of SMAD phosphorylation. Application of structure-based drug design to the novel pyrrolotriazine chemotype resulted in improved binding affinity (Ki apparentâ¯=â¯0.14â¯nM), long residence time (T1/2â¯>â¯120â¯min) and significantly improved potency in the PSMAD cellular assay (IC50â¯=â¯24â¯nM). Several analogs inhibited phosphorylation of SMAD both in vitro and in vivo. Additionally, inhibition of TGFß-stimulated phospho-SMAD was observed in primary human T cells.
Asunto(s)
Compuestos Bicíclicos con Puentes/química , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Sitios de Unión , Compuestos Bicíclicos con Puentes/síntesis química , Compuestos Bicíclicos con Puentes/farmacología , Células Cultivadas , Cristalografía por Rayos X , Diseño de Fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Humanos , Simulación de Dinámica Molecular , Fosforilación , Unión Proteica , Proteínas Serina-Treonina Quinasas/metabolismo , Estructura Terciaria de Proteína , Pirroles/síntesis química , Pirroles/química , Pirroles/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Proteínas Smad/metabolismo , Relación Estructura-Actividad , Linfocitos T/citología , Linfocitos T/metabolismo , Tiazinas/síntesis química , Tiazinas/química , Tiazinas/metabolismoRESUMEN
Current clinical anti-CD40 biologic agents include both antagonist molecules for the treatment of autoimmune diseases and agonist molecules for immuno-oncology, yet the relationship between CD40 epitope and these opposing biological outcomes is not well defined. This report describes the identification of potent antagonist domain antibodies (dAbs) that bind to a novel human CD40-specific epitope that is divergent in the CD40 of nonhuman primates. A similarly selected anti-cynomolgus CD40 dAb recognizing the homologous epitope is also a potent antagonist. Mutagenesis, biochemical, and X-ray crystallography studies demonstrate that the epitope is distinct from that of CD40 agonists. Both the human-specific and cynomolgus-specific molecules remain pure antagonists even when formatted as bivalent Fc-fusion proteins, making this an attractive therapeutic format for targeting hCD40 in autoimmune indications.
Asunto(s)
Antígenos CD40/inmunología , Epítopos/inmunología , Animales , Enfermedades Autoinmunes/inmunología , Cristalografía por Rayos X/métodos , Humanos , Macaca fascicularisRESUMEN
The cytokine TGF-ß modulates a number of cellular activities and plays a critical role in development, hemostasis and physiology, as well as in diseases including cancer and fibrosis. TGF-ß signals through two transmembrane serine/threonine kinase receptors: TGFßR1 and TGFßR2. Multiple structures of the TGFßR1 kinase domain are known, but the structure of TGFßR2 remains unreported. Wild-type TGFßR2 kinase domain was refractory to crystallization, leading to the design of two mutated constructs: firstly, a TGFßR1 chimeric protein with seven ATP-site residues mutated to their counterparts in TGFßR2, and secondly, a reduction of surface entropy through mutation of six charged residues on the surface of the TGFßR2 kinase domain to alanines. These yielded apo and inhibitor-bound crystals that diffracted to high resolution (<2â Å). Comparison of these structures with those of TGFßR1 reveal shared ligand contacts as well as differences in the ATP-binding sites, suggesting strategies for the design of pan and selective TGFßR inhibitors.
Asunto(s)
Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/química , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Receptores de Factores de Crecimiento Transformadores beta/química , Adenosina Trifosfato/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Humanos , Ligandos , Modelos Moleculares , Unión Proteica , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Inhibidores de Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptor Tipo II de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/metabolismoRESUMEN
The structure of death receptor 4 (DR4) in complex with TNF-related apoptosis-inducing ligand (TRAIL) has been determined at 3â Å resolution and compared with those of previously determined DR5-TRAIL complexes. Consistent with the high sequence similarity between DR4 and DR5, the overall arrangement of the DR4-TRAIL complex does not differ substantially from that of the DR5-TRAIL complex. However, subtle differences are apparent. In addition, solution interaction studies were carried out that show differences in the thermodynamics of binding DR4 or DR5 with TRAIL.
Asunto(s)
Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/química , Ligando Inductor de Apoptosis Relacionado con TNF/química , Secuencia de Aminoácidos , Calorimetría , Cristalización , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/aislamiento & purificación , Ligando Inductor de Apoptosis Relacionado con TNF/aislamiento & purificación , TermodinámicaRESUMEN
Adnectins are targeted biologics derived from the tenth type III domain of human fibronectin (¹°Fn3), a member of the immunoglobulin superfamily. Target-specific binders are selected from libraries generated by diversifying the three ¹°Fn3 loops that are analogous to the complementarity determining regions of antibodies. The crystal structures of two Adnectins were determined, each in complex with its therapeutic target, EGFR or IL-23. Both Adnectins bind different epitopes than those bound by known monoclonal antibodies. Molecular modeling suggests that some of these epitopes might not be accessible to antibodies because of the size and concave shape of the antibody combining site. In addition to interactions from the Adnectin diversified loops, residues from the N terminus and/or the ß strands interact with the target proteins in both complexes. Alanine-scanning mutagenesis confirmed the calculated binding energies of these ß strand interactions, indicating that these nonloop residues can expand the available binding footprint.
Asunto(s)
Receptores ErbB/química , Fibronectinas/química , Interleucina-23/química , Fragmentos de Péptidos/química , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Cristalografía por Rayos X , Fibronectinas/genética , Humanos , Enlace de Hidrógeno , Modelos Moleculares , Datos de Secuencia Molecular , Complejos Multiproteicos/química , Mutagénesis Sitio-Dirigida , Fragmentos de Péptidos/genética , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Homología Estructural de Proteína , Resonancia por Plasmón de Superficie , Propiedades de SuperficieRESUMEN
A new class of lymphocyte function-associated antigen-1 (LFA-1) antagonists is described. Elaboration of the 2,3-dihydro-1H-pyrrolizin-5(7aH)-one scaffold resulted in the synthesis of potent inhibitors of the LFA-1/ICAM-1 interaction. Along with the in vitro activity, we present the X-ray crystal structure of the complex of compound 9b, in a novel binding mode to the I-domain of LFA-1.
Asunto(s)
Química Farmacéutica/métodos , Antígeno-1 Asociado a Función de Linfocito/química , Pirroles/química , Cristalografía por Rayos X , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Células HeLa , Humanos , Concentración 50 Inhibidora , Modelos Químicos , Conformación Molecular , Estereoisomerismo , Temperatura , Rayos XRESUMEN
Synthesis and SAR of substituted pyrrolotriazine-4-one analogues as Eg5 inhibitors are described. Many of these analogues displayed potent inhibitory activities in the Eg5 ATPase and A2780 cell proliferation assays. In addition, pyrrolotriazine-4-one analogue 26 demonstrated in vivo efficacy in an iv P388 murine leukemia model. Both NMR and X-ray crystallographic studies revealed that these analogues bind to an allosteric site on the Eg5 protein.
Asunto(s)
Cinesinas/antagonistas & inhibidores , Pirroles/síntesis química , Pirroles/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Humanos , Espectroscopía de Resonancia Magnética , Ratones , Modelos Moleculares , Pirroles/química , Relación Estructura-ActividadRESUMEN
In a high-throughput screening effort, a series of tetrahydroisoquinolines was identified as modest inhibitors of human Eg5. A medicinal chemistry optimization effort led to the identification of R-4-(3-hydroxyphenyl)-N,N-7,8-tetramethyl-3,4-dihydroisoquinoline-2(1H)-carboxamide (32a) as a potent inhibitor of human Eg5 (ATPase IC50 104 nM) with good anti-proliferative activity in A2780 cells (IC50 234 nM).