Improving the Pharmacokinetic and CYP Inhibition Profiles of Azaxanthene-Based Glucocorticoid Receptor ModulatorsIdentification of (<i>S</i>)‑5-(2-(9-Fluoro-2-(4-(2-hydroxypropan-2-yl)phenyl)‑5<i>H</i>‑chromeno[2,3‑<i>b</i>]pyridin-5-yl)-2-methylpropanamido)‑<i>N</i>‑(tetrahydro‑2<i>H</i>‑pyran-4-yl)-1,3,4-thiadiazole-2-carboxamide (BMS-341)

An empirical approach to improve the microsomal stability and CYP inhibition profile of lead compounds <b>1a</b> and <b>1b</b> led to the identification of <b>5</b> (BMS-341) as a dissociated glucocorticoid receptor modulator. Compound <b>5</b> showed significant improvements in pharmacokinetic properties and, unlike compounds <b>1a</b>–<b>b</b>, displayed a linear, dose-dependent pharmacokinetic profile in rats. When tested in a chronic model of adjuvant-induced arthritis in rat, the ED₅₀ of <b>5</b> (0.9 mg/kg) was superior to that of both <b>1a</b> and <b>1b</b> (8 and 17 mg/kg, respectively)

Discovery and Structure–Activity Relationship (SAR) of a Series of Ethanolamine-Based Direct-Acting Agonists of Sphingosine-1-phosphate (S1P₁)

Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid metabolite that regulates a multitude of physiological processes such as lymphocyte trafficking, cardiac function, vascular development, and inflammation. Because of the ability of S1P₁ receptor agonists to suppress lymphocyte egress, they have great potential as therapeutic agents in a variety of autoimmune diseases. In this article, the discovery of selective, direct acting S1P₁ agonists utilizing an ethanolamine scaffold containing a terminal carboxylic acid is described. Potent S1P₁ agonists such as compounds <b>18a</b> and <b>19a</b> which have greater than 1000-fold selectivity over S1P₃ are described. These compounds efficiently reduce blood lymphocyte counts in rats through 24 h after single doses of 1 and 0.3 mpk, respectively. Pharmacodynamic properties of both compounds are discussed. Compound <b>19a</b> was further studied in two preclinical models of disease, exhibiting good efficacy in both the rat adjuvant arthritis model (AA) and the mouse experimental autoimmune encephalomyelitis model (EAE)

Potent and Selective Agonists of Sphingosine 1‑Phosphate 1 (S1P₁): Discovery and SAR of a Novel Isoxazole Based Series

Sphingosine 1-phosphate (S1P) is the endogenous ligand for the sphingosine 1-phosphate receptors (S1P_1–5) and evokes a variety of cellular responses through their stimulation. The interaction of S1P with the S1P receptors plays a fundamental physiological role in a number of processes including vascular development and stabilization, lymphocyte migration, and proliferation. Agonism of S1P₁, in particular, has been shown to play a significant role in lymphocyte trafficking from the thymus and secondary lymphoid organs, resulting in immunosuppression. This article will detail the discovery and SAR of a potent and selective series of isoxazole based full agonists of S1P₁. Isoxazole <b>6d</b> demonstrated impressive efficacy when administered orally in a rat model of arthritis and in a mouse experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis

Identification and Preclinical Pharmacology of BMS-986104: A Differentiated S1P₁ Receptor Modulator in Clinical Trials

Clinical validation of S1P receptor modulation therapy was achieved with the approval of fingolimod (Gilenya, <b>1</b>) as the first oral therapy for relapsing remitting multiple sclerosis. However, <b>1</b> causes a dose-dependent reduction in the heart rate (bradycardia), which occurs within hours after first dose. We disclose the identification of clinical compound BMS-986104 (<b>3d</b>), a novel S1P₁ receptor modulator, which demonstrates ligand-biased signaling and differentiates from <b>1</b> in terms of cardiovascular and pulmonary safety based on preclinical pharmacology while showing equivalent efficacy in a T-cell transfer colitis model

Small Molecule Reversible Inhibitors of Bruton’s Tyrosine Kinase (BTK): Structure–Activity Relationships Leading to the Identification of 7‑(2-Hydroxypropan-2-yl)-4-[2-methyl-3-(4-oxo-3,4-dihydroquinazolin-3-yl)phenyl]‑9<i>H</i>‑carbazole-1-carboxamide (BMS-935177)

Bruton’s tyrosine kinase (BTK) belongs to the TEC family of nonreceptor tyrosine kinases and plays a critical role in multiple cell types responsible for numerous autoimmune diseases. This article will detail the structure–activity relationships (SARs) leading to a novel second generation series of potent and selective reversible carbazole inhibitors of BTK. With an excellent pharmacokinetic profile as well as demonstrated in vivo activity and an acceptable safety profile, 7-(2-hydroxypropan-2-yl)-4-[2-methyl-3-(4-oxo-3,4-dihydro­quinazolin-3-yl)­phenyl]-9<i>H</i>-carbazole-1-carboxamide <b>6</b> (BMS-935177) was selected to advance into clinical development

Identification of Tricyclic Agonists of Sphingosine-1-phosphate Receptor 1 (S1P₁) Employing Ligand-Based Drug Design

Fingolimod (<b>1</b>) is the first approved oral therapy for the treatment of relapsing remitting multiple sclerosis. While the phosphorylated metabolite of fingolimod was found to be a nonselective S1P receptor agonist, agonism specifically of S1P₁ is responsible for the peripheral blood lymphopenia believed to be key to its efficacy. Identification of modulators that maintain activity on S1P₁ while sparing activity on other S1P receptors could offer equivalent efficacy with reduced liabilities. We disclose in this paper a ligand-based drug design approach that led to the discovery of a series of potent tricyclic agonists of S1P₁ with selectivity over S1P₃ and were efficacious in a pharmacodynamic model of suppression of circulating lymphocytes. Compound <b>10</b> had the desired pharmacokinetic (PK) and pharmacodynamic (PD) profile and demonstrated maximal efficacy when administered orally in a rat adjuvant arthritis model

Discovery of Pyrrolidine-Containing GPR40 Agonists: Stereochemistry Effects a Change in Binding Mode

A novel series of pyrrolidine-containing GPR40 agonists is described as a potential treatment for type 2 diabetes. The initial pyrrolidine hit was modified by moving the position of the carboxylic acid, a key pharmacophore for GPR40. Addition of a 4-<i>cis</i>-CF₃ to the pyrrolidine improves the human GPR40 binding <i>K</i>_i and agonist efficacy. After further optimization, the discovery of a minor enantiomeric impurity with agonist activity led to the finding that enantiomers <b>(</b><i><b>R,R</b></i><b>)-68</b> and <b>(</b><i><b>S,S</b></i><b>)-68</b> have differential effects on the radioligand used for the binding assay, with <b>(</b><i><b>R,R</b></i><b>)-68</b> potentiating the radioligand and <b>(</b><i><b>S,S</b></i><b>)-68</b> displacing the radioligand. Compound <b>(</b><i><b>R</b></i>,<i><b>R</b></i><b>)-68</b> activates both G_q-coupled intracellular Ca²⁺ flux and G_s-coupled cAMP accumulation. This signaling bias results in a dual mechanism of action for compound <b>(</b><i><b>R</b></i>,<i><b>R</b></i><b>)-68</b>, demonstrating glucose-dependent insulin and GLP-1 secretion in vitro. In vivo, compound <b>(</b><i><b>R</b></i>,<i><b>R</b></i><b>)-68</b> significantly lowers plasma glucose levels in mice during an oral glucose challenge, encouraging further development of the series

Discovery of Clinical Candidate 2‑((2<i>S</i>,6<i>S</i>)‑2-Phenyl-6-hydroxyadamantan-2-yl)-1-(3′-hydroxyazetidin-1-yl)ethanone [BMS-816336], an Orally Active Novel Selective 11β-Hydroxysteroid Dehydrogenase Type 1 Inhibitor

BMS-816336 (<b>6n-2</b>), a hydroxy-substituted adamantyl acetamide, has been identified as a novel, potent inhibitor against human 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme (IC₅₀ 3.0 nM) with >10000-fold selectivity over human 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2). <b>6n-2</b> exhibits a robust acute pharmacodynamic effect in cynomolgus monkeys (ED₅₀ 0.12 mg/kg) and in DIO mice. It is orally bioavailable (%<i>F</i> ranges from 20 to 72% in preclinical species) and has a predicted pharmacokinetic profile of a high peak to trough ratio and short half-life in humans. This ADME profile met our selection criteria for once daily administration, targeting robust inhibition of 11β-HSD1 enzyme for the first 12 h period after dosing followed by an “inhibition holiday” so that the potential for hypothalamic–pituitary–adrenal (HPA) axis activation might be mitigated. <b>6n-2</b> was found to be well-tolerated in phase 1 clinical studies and represents a potential new treatment for type 2 diabetes, metabolic syndrome, and other human diseases modulated by glucocorticoid control