ABSTRACT
As the desire for a shortened design/make/test/learn cycle increases in early drug discovery, the pressure to rapidly deliver drug metabolism pharmacokinetic data continues to rise. From a bioanalytical standpoint, in vitro assays are challenging because they are amenable to automation and thus capable of generating a high number of samples for analysis. To keep up with analysis demands, automated method development workflows, rapid sample analysis approaches and efficient data analysis software must be utilized. This work provides an outline of how we implemented those three aspects to provide bioanalytical support for in vitro drug metabolism pharmacokinetic assays, which include developing hundreds of mass spectrometry methods and analyzing thousands of samples per week, while delivering a median bioanalytical turnaround time of 1-2 business days.
Subject(s)
Drug Discovery , Software , Drug Discovery/methods , Mass Spectrometry/methods , Automation , Research DesignABSTRACT
Investigation of TRPV4 as a potential target for the treatment of pulmonary edema associated with heart failure generated a novel series of acyclic amine inhibitors displaying exceptional potency and PK properties. The series arose through a scaffold hopping approach, which relied on use of an internal H-bond to replace a saturated heterocyclic ring. Optimization of the lead through investigation of both aryl regions revealed approaches to increase potency through substituents believed to enhance separate intramolecular and intermolecular H-bond interactions. A proposed internal H-bond between the amine and neighboring benzenesulfonamide was stabilized by electronically modulating the benzenesulfonamide. In the aryl ether moiety, substituents para to the nitrile demonstrated an electronic effect on TRPV4 recognition. Finally, the acyclic amines inactivated CYP3A4 and this liability was addressed by modifications that sterically preclude formation of a putative metabolic intermediate complex to deliver advanced TRPV4 antagonists as leads for discovery of novel medicines.
Subject(s)
Diamines/chemistry , Sulfonamides/chemistry , TRPV Cation Channels/antagonists & inhibitors , Animals , Cytochrome P-450 CYP3A/metabolism , Diamines/chemical synthesis , Diamines/metabolism , Diamines/pharmacokinetics , Drug Design , Humans , Hydrogen Bonding/drug effects , Microsomes, Liver/metabolism , Molecular Structure , Protein Binding , Rats , Stereoisomerism , Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/metabolism , Sulfonamides/pharmacokinetics , TRPV Cation Channels/chemistry , TRPV Cation Channels/metabolismABSTRACT
GSK3527497, a preclinical candidate for the inhibition of TRPV4, was identified starting from the previously reported pyrrolidine sulfonamide TRPV4 inhibitors 1 and 2. Optimization of projected human dose was accomplished by specifically focusing on in vivo pharmacokinetic parameters CLu, Vdssu, and MRT. We highlight the use of conformational changes as a novel approach to modulate Vdssu and present results that suggest that molecular-shape-dependent binding to tissue components governs Vdssu in addition to bulk physicochemical properties. Optimization of CLu within the series was guided by in vitro metabolite identification, and the poor FaSSIF solubility imparted by the crystalline properties of the pyrrolidine diol scaffold was improved by the introduction of a charged moiety to enable excellent exposure from high crystalline doses. GSK3527497 is a preclinical candidate suitable for oral and iv administration that is projected to inhibit TRPV4 effectively in patients from a low daily clinical dose.
Subject(s)
Pyrrolidines/chemistry , Sulfonamides/chemistry , TRPV Cation Channels/antagonists & inhibitors , Administration, Oral , Animals , Drug Evaluation, Preclinical , Half-Life , Humans , Inhibitory Concentration 50 , Pyrrolidines/metabolism , Rats , Rats, Sprague-Dawley , Solubility , Structure-Activity Relationship , Sulfonamides/metabolism , TRPV Cation Channels/metabolismABSTRACT
GSK2798745, a clinical candidate, was identified as an inhibitor of the transient receptor potential vanilloid 4 (TRPV4) ion channel for the treatment of pulmonary edema associated with congestive heart failure. We discuss the lead optimization of this novel spirocarbamate series and specifically focus on our strategies and solutions for achieving desirable potency, rat pharmacokinetics, and physicochemical properties. We highlight the use of conformational bias to deliver potency and optimization of volume of distribution and unbound clearance to enable desirable in vivo mean residence times.
ABSTRACT
Pulmonary edema is a common ailment of heart failure patients and has remained an unmet medical need due to dose-limiting side effects associated with current treatments. Preclinical studies in rodents have suggested that inhibition of transient receptor potential vanilloid-4 (TRPV4) cation channels may offer an alternative-and potentially superior-therapy. Efforts directed toward small-molecule antagonists of the TRPV4 receptor have led to the discovery of a novel sulfone pyrrolidine sulfonamide chemotype exemplified by lead compound 6. Design elements toward the optimization of TRPV4 activity, selectivity, and pharmacokinetic properties are described. Activity of leading exemplars 19 and 27 in an in vivo model suggestive of therapeutic potential is highlighted herein.
Subject(s)
Pulmonary Edema/drug therapy , Pyrrolidines/pharmacology , Sulfonamides/pharmacology , Sulfones/pharmacology , TRPV Cation Channels/antagonists & inhibitors , Animals , Drug Evaluation, Preclinical , Humans , Male , Pyrrolidines/chemistry , Pyrrolidines/pharmacokinetics , Rats, Sprague-Dawley , Structure-Activity Relationship , Sulfonamides/chemistry , Sulfonamides/pharmacokinetics , Sulfones/chemistry , Sulfones/pharmacokineticsABSTRACT
Transient Receptor Potential Vanilloid 4 (TRPV4) is a member of the Transient Receptor Potential (TRP) superfamily of cation channels. TRPV4 is expressed in the vascular endothelium in the lung and regulates the integrity of the alveolar septal barrier. Increased pulmonary vascular pressure evokes TRPV4-dependent pulmonary edema, and therefore, inhibition of TRPV4 represents a novel approach for the treatment of pulmonary edema associated with conditions such as congestive heart failure. Herein we report the discovery of an orally active, potent, and selective TRPV4 blocker, 3-(1,4'-bipiperidin-1'-ylmethyl)-7-bromo-N-(1-phenylcyclopropyl)-2-[3-(trifluoromethyl)phenyl]-4-quinolinecarboxamide (GSK2193874, 28) after addressing an unexpected off-target cardiovascular liability observed from in vivo studies. GSK2193874 is a selective tool for elucidating TRPV4 biology both in vitro and in vivo.
ABSTRACT
High-throughput screening and subsequent hit optimization identified 1-piperidinylbenzimidazoles, exemplified by compound 1, as TRPV4 inhibitors. Lead optimization identified potent TRPV4 blocker 19, which has good target activity and pharmacokinetic properties. Inhibitor 19 was then profiled in an in vivo rat model, demonstrating its ability to inhibit TRPV4-mediated pulmonary edema.
ABSTRACT
Pulmonary edema resulting from high pulmonary venous pressure (PVP) is a major cause of morbidity and mortality in heart failure (HF) patients, but current treatment options demonstrate substantial limitations. Recent evidence from rodent lungs suggests that PVP-induced edema is driven by activation of pulmonary capillary endothelial transient receptor potential vanilloid 4 (TRPV4) channels. To examine the therapeutic potential of this mechanism, we evaluated TRPV4 expression in human congestive HF lungs and developed small-molecule TRPV4 channel blockers for testing in animal models of HF. TRPV4 immunolabeling of human lung sections demonstrated expression of TRPV4 in the pulmonary vasculature that was enhanced in sections from HF patients compared to controls. GSK2193874 was identified as a selective, orally active TRPV4 blocker that inhibits Ca(2+) influx through recombinant TRPV4 channels and native endothelial TRPV4 currents. In isolated rodent and canine lungs, TRPV4 blockade prevented the increased vascular permeability and resultant pulmonary edema associated with elevated PVP. Furthermore, in both acute and chronic HF models, GSK2193874 pretreatment inhibited the formation of pulmonary edema and enhanced arterial oxygenation. Finally, GSK2193874 treatment resolved pulmonary edema already established by myocardial infarction in mice. These findings identify a crucial role for TRPV4 in the formation of HF-induced pulmonary edema and suggest that TRPV4 blockade is a potential therapeutic strategy for HF patients.
Subject(s)
Heart Failure/complications , Membrane Transport Modulators/administration & dosage , Membrane Transport Modulators/therapeutic use , Pulmonary Edema/drug therapy , Pulmonary Edema/prevention & control , TRPV Cation Channels/antagonists & inhibitors , Administration, Oral , Animals , Blood Pressure/drug effects , Calcium/metabolism , Disease Models, Animal , Diuretics/pharmacology , Endothelium/drug effects , Endothelium/metabolism , Endothelium/pathology , Heart Failure/pathology , Heart Failure/physiopathology , Heart Rate/drug effects , Humans , In Vitro Techniques , Ion Channel Gating/drug effects , Lung/drug effects , Lung/metabolism , Lung/pathology , Membrane Transport Modulators/chemistry , Membrane Transport Modulators/pharmacology , Mice , Mice, Knockout , Permeability/drug effects , Protein Transport/drug effects , Pulmonary Edema/etiology , Pulmonary Edema/pathology , Rats , TRPV Cation Channels/metabolism , Water-Electrolyte Balance/drug effectsABSTRACT
The discovery and evaluation of potent and long-acting oral sulfonamidopyrrolidin-2-one factor Xa inhibitors with tetrahydroisoquinoline and benzazepine P4 motifs are described. Unexpected selectivity issues versus tissue plasminogen activator in the former series were addressed in the later, delivering a robust candidate for progression towards clinical studies.
Subject(s)
Benzazepines/chemical synthesis , Factor Xa Inhibitors , Serine Proteinase Inhibitors/chemistry , Tetrahydroisoquinolines/chemistry , Administration, Oral , Animals , Benzazepines/administration & dosage , Benzazepines/pharmacology , Crystallography, X-Ray , Drug Evaluation, Preclinical , Molecular Structure , Rats , Serine Proteinase Inhibitors/administration & dosage , Tetrahydroisoquinolines/administration & dosage , Tetrahydroisoquinolines/pharmacologyABSTRACT
Lead compound 1 was successfully redesigned to provide compounds with improved pharmacokinetic profiles for this series of human urotensin-II antagonists. Replacement of the 2-pyrrolidinylmethyl-3-phenyl-piperidine core of 1 with a substituted N-methyl-2-(1-pyrrolidinyl)ethanamine core as in compound 7 resulted in compounds with improved oral bioavailability in rats. The relationship between stereochemistry and selectivity for hUT over the kappa-opioid receptor was also explored.
Subject(s)
Chemistry, Pharmaceutical/methods , Urotensins/antagonists & inhibitors , Administration, Oral , Animals , Brain/metabolism , Chromatography, High Pressure Liquid , Diamines/chemistry , Drug Design , Humans , Inhibitory Concentration 50 , Models, Chemical , Rats , Receptors, Opioid, kappa/chemistry , Stereoisomerism , Structure-Activity Relationship , Urotensins/chemistryABSTRACT
This work describes the development of potent and selective human Urotensin-II receptor antagonists starting from lead compound 1, (3,4-dichlorophenyl)methyl{2-oxo-2-[3-phenyl-2-(1-pyrrolidinylmethyl)-1-piperidinyl]ethyl}amine. Several problems relating to oral bioavailability, cytochrome P450 inhibition, and off-target activity at the kappa opioid receptor and cardiac sodium channel were addressed during lead development. hUT binding affinity relative to compound 1 was improved by more than 40-fold in some analogs, and a structural modification was identified which significantly attenuated both off-target activities.
Subject(s)
Aniline Compounds/pharmacology , Piperidones/pharmacology , Receptors, G-Protein-Coupled/antagonists & inhibitors , Administration, Oral , Aniline Compounds/chemical synthesis , Aniline Compounds/chemistry , Animals , Biological Availability , Cell Line , Drug Evaluation, Preclinical , Humans , Molecular Structure , Molecular Weight , Piperidones/chemical synthesis , Piperidones/chemistry , Rats , Small Molecule Libraries , Stereoisomerism , Structure-Activity RelationshipABSTRACT
N,N'-diarylsquaramides were prepared and evaluated as antagonists of CXCR2. The compounds were found to be potent and selective antagonists of CXCR2. Significant differences in SAR was observed relative to the previously described N,N'-diarylurea series. As was the case in the N,N'-diarylurea series, placing sulfonamide substituent adjacent to the acidic phenol significantly reduced the clearance in rat pharmacokinetic studies.
Subject(s)
Cyclobutanes/chemical synthesis , Cyclobutanes/pharmacology , Cyclobutanes/pharmacokinetics , Receptors, Interleukin-8B/antagonists & inhibitors , Urea/analogs & derivatives , Urea/chemical synthesis , Urea/pharmacology , Urea/pharmacokinetics , Animals , CHO Cells , Chemical Phenomena , Chemistry, Physical , Cricetinae , Cricetulus , Indicators and Reagents , Mass Spectrometry , Phenols/chemistry , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship , Sulfonamides/chemistryABSTRACT
The syntheses, in vitro characterizations, and rat and monkey in vivo pharmacokinetic profiles of a series of 5-, 6-, and 7-methyl-substituted azepanone-based cathepsin K inhibitors are described. Depending on the particular regiochemical substitution and stereochemical configuration, methyl-substituted azepanones were identified that had widely varied cathepsin K inhibitory potency as well as pharmacokinetic properties compared to the 4S-parent azepanone analogue, 1 (human cathepsin K, K(i,app) = 0.16 nM, rat oral bioavailability = 42%, rat in vivo clearance = 49.2 mL/min/kg). Of particular note, the 4S-7-cis-methylazepanone analogue, 10, had a K(i,app) = 0.041 nM vs human cathepsin K and 89% oral bioavailability and an in vivo clearance rate of 19.5 mL/min/kg in the rat. Hypotheses that rationalize some of the observed characteristics of these closely related analogues have been made using X-ray crystallography and conformational analysis. These examples demonstrate the potential for modulation of pharmacological properties of cathepsin inhibitors by substituting the azepanone core. The high potency for inhibition of cathepsin K coupled with the favorable rat and monkey pharmacokinetic characteristics of compound 10, also known as SB-462795 or relacatib, has made it the subject of considerable in vivo evaluation for safety and efficacy as an inhibitor of excessive bone resorption in rat, monkey, and human studies, which will be reported elsewhere.