ABSTRACT
Toll-like receptor (TLR) 7 and TLR8 are endosomal sensors of the innate immune system that are activated by GU-rich single stranded RNA (ssRNA). Multiple genetic and functional lines of evidence link chronic activation of TLR7/8 to the pathogenesis of systemic autoimmune diseases (sAID) such as Sjögren's syndrome (SjS) and systemic lupus erythematosus (SLE). This makes targeting TLR7/8-induced inflammation with small-molecule inhibitors an attractive approach for the treatment of patients suffering from systemic autoimmune diseases. Here, we describe how structure-based optimization of compound 2 resulted in the discovery of 34 (MHV370, (S)-N-(4-((5-(1,6-dimethyl-1H-pyrazolo[3,4-b]pyridin-4-yl)-3-methyl-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridin-1-yl)methyl)bicyclo[2.2.2]octan-1-yl)morpholine-3-carboxamide). Its in vivo activity allows for further profiling toward clinical trials in patients with autoimmune disorders, and a Phase 2 proof of concept study of MHV370 has been initiated, testing its safety and efficacy in patients with Sjögren's syndrome and mixed connective tissue disease.
ABSTRACT
Antagonism of the Toll-like receptors (TLRs) 7 and TLR8 has been hypothesized to be beneficial to patients suffering from autoimmune conditions. A phenotypic screen for small molecule antagonists of TLR7/8 was carried out in a murine P4H1 cell line. Compound 1 was identified as a hit that showed antagonistic activity on TLR7 and TLR8 but not TLR9, as shown on human peripheral blood mononuclear cells (hPBMCs). It was functionally cross reactive with mouse TLR7 but lacked oral exposure and had only modest potency. Chemical optimization resulted in 2, which showed in vivo efficacy following intraperitoneal administration. Further optimization resulted in 8 which had excellent in vitro activity, exposure and in vivo activity. Additional work to improve physical properties resulted in 15, an advanced lead that had favorable in vitro and exposure properties. It was further demonstrated that activity of the series tracked with binding to the extracellular domain of TLR7 implicating that the target of this series are endosomal TLRs rather than downstream signaling pathways.
Subject(s)
Piperazine/chemistry , Toll-Like Receptor 7/metabolism , Toll-Like Receptor 8/metabolism , Administration, Oral , Animals , Cell Line , Drug Evaluation, Preclinical , Half-Life , Humans , Interferon-gamma/metabolism , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/metabolism , Male , Mice , Mice, Inbred BALB C , Piperazine/administration & dosage , Piperazine/pharmacokinetics , Piperazine/pharmacology , Spleen/cytology , Spleen/drug effects , Spleen/metabolism , Structure-Activity Relationship , Toll-Like Receptor 7/antagonists & inhibitors , Toll-Like Receptor 8/antagonists & inhibitorsABSTRACT
Continuing studies based on dihydroquinoline glucocorticoid receptor agonists lead to the discovery of a series of C4-oxime analogs. Representative compounds exhibited potent transrepression activity with minimal transactivation of phosphoenolpyruvate caboxykinase (PEPCK), a key protein in the gluconeogenesis pathway. These compounds represent promising leads in identifying GR agonists with high anti-inflammatory activity and attenuated potential for glucose elevation.
Subject(s)
Carboxy-Lyases/metabolism , Quinolines/pharmacology , Receptors, Glucocorticoid/agonists , Enzyme Activation , Quinolines/chemistry , Structure-Activity RelationshipABSTRACT
Continuing studies on tetrahydroquinoline glucocorticoid receptor anti-inflammatory agents lead to the identification of several tetrahydroquinolin-3-yl carbamates that exhibited steroid-like activity in in vitro transrepression assays with reduced transactivation of phosphoenol pyruvate carboxykinase (PEPCK), a key enzyme in the gluconeogenesis pathway.
Subject(s)
Carboxy-Lyases/metabolism , Quinolines/pharmacology , Receptors, Glucocorticoid/agonists , Enzyme ActivationABSTRACT
A series of tetrahydroquinoline derivatives were synthesized and profiled for their ability to act as glucocorticoid receptor selective modulators. Structure-activity relationships of the tetrahydroquinoline B-ring lead to the discovery of orally available GR-selective agonists with high in vivo activity.
Subject(s)
Quinolines/pharmacology , Receptors, Glucocorticoid/agonists , Administration, Oral , Animals , Drug Discovery , Enzyme-Linked Immunosorbent Assay , Humans , Quinolines/administration & dosage , Quinolines/chemistry , Rats , Rats, Sprague-Dawley , Structure-Activity RelationshipABSTRACT
We have previously disclosed a series of glucocorticoid receptor (GR) ligands derived from 6-indole-1,2,3,4-tetrahydroquinolines through structure-activity relationship (SAR) of the pendent C6-indole ring. In parallel with this effort, we now report SAR of the tetrahydroquinoline A-ring that identified the importance of a C3 hydroxyl in improving GR selectivity within a series of non-steroidal GR agonists.
