title: Benzoxazepines Achieve Potent Suppression of IL-17 Release in Human T-Helper 17 (TH 17) Cells through an Induced-Fit Binding Mode to the Nuclear Receptor RORγ.
abstract: RORγt, an isoform of the retinoic acid-related orphan receptor gamma (RORc, RORγ), has been identified as the master regulator of T-helper 17 (TH 17) cell function and development, making it an attractive target for the treatment of autoimmune diseases. Validation for this target comes from antibodies targeting interleukin-17 (IL-17), the signature cytokine produced by TH 17 cells, which have shown impressive results in clinical trials. Through focused screening of our compound collection, we identified a series of N-sulfonylated benzoxazepines, which displayed micromolar affinity for the RORγ ligand-binding domain (LBD) in a radioligand binding assay. Optimization of these initial hits resulted in potent binders, which dose-dependently decreased the ability of the RORγ-LBD to interact with a peptide derived from steroid receptor coactivator 1, and inhibited the release of IL-17 secretion from isolated and cultured human TH 17 cells with nanomolar potency. A cocrystal structure of inverse agonist 15 (2-chloro-6-fluoro-N-(4-{[3-(trifluoromethyl)phenyl]sulfonyl}-2,3,4,5-tetrahydro-1,4-benzoxazepin-7-yl)benzamide) bound to the RORγ-LBD illustrated that both hydrophobic interactions, leading to an induced fit around the substituted benzamide moiety of 15, as well as a hydrogen bond from the amide NH to His479 seemed to be important for the mechanism of action. This structure is compared with the structure of agonist 25 (N-(2-fluorophenyl)-4-[(4-fluorophenyl)sulfonyl]-2,3,4,5-tetrahydro-1,4-benzoxazepin-6-amine ) and structures of other known RORγ modulators.
authors.affiliation: Department of Medicinal Chemistry, AstraZeneca, Respiratory, Inflammation and Autoimmunity iMed, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Roine I
authors.initials: RI
authors.lastname: Olsson
authors.affiliation: Discovery Sciences, AstraZeneca, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Yafeng
authors.initials: Y
authors.lastname: Xue
authors.affiliation: Department of Medicinal Chemistry, AstraZeneca, Respiratory, Inflammation and Autoimmunity iMed, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Stefan
authors.initials: S
authors.lastname: von Berg
authors.affiliation: Discovery Sciences, AstraZeneca, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Aagaard
authors.affiliation: Discovery Sciences, AstraZeneca, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Jane
authors.initials: J
authors.lastname: McPheat
authors.affiliation: Discovery Sciences, AstraZeneca, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Eva L
authors.initials: EL
authors.lastname: Hansson
authors.affiliation: Discovery Sciences, AstraZeneca, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Jenny
authors.initials: J
authors.lastname: Bernström
authors.affiliation: Discovery Sciences, AstraZeneca, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Pia
authors.initials: P
authors.lastname: Hansson
authors.affiliation: Department of Bioscience, AstraZeneca, Respiratory, Inflammation and Autoimmunity iMed, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Jirholt
authors.affiliation: Department of Bioscience, AstraZeneca, Respiratory, Inflammation and Autoimmunity iMed, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Hanna
authors.initials: H
authors.lastname: Grindebacke
authors.affiliation: Department of Bioscience, AstraZeneca, Respiratory, Inflammation and Autoimmunity iMed, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Agnes
authors.initials: A
authors.lastname: Leffler
authors.affiliation: Department of Medicinal Chemistry, Pharmaron Beijing Co., 6 Taihe Road, BDA, Beijing, 10076, P. R. China.
authors.forename: Rongfeng
authors.initials: R
authors.lastname: Chen
authors.affiliation: Department of Medicinal Chemistry, Pharmaron Beijing Co., 6 Taihe Road, BDA, Beijing, 10076, P. R. China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Xiong
authors.affiliation: Department of Medicinal Chemistry, Pharmaron Beijing Co., 6 Taihe Road, BDA, Beijing, 10076, P. R. China.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Ge
authors.affiliation: Department of Medicinal Chemistry, AstraZeneca, Respiratory, Inflammation and Autoimmunity iMed, Pepparedsleden 1, 43183, Mölndal, Sweden.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Hansson
authors.affiliation: Department of Medicinal Chemistry, AstraZeneca, Respiratory, Inflammation and Autoimmunity iMed, Pepparedsleden 1, 43183, Mölndal, Sweden. Frank.Narjes@astrazeneca.com.
authors.forename: Frank
authors.identifier: http://orcid.org/0000-0002-3104-7771
authors.initials: F
authors.lastname: Narjes
mesh_terms: D001665:Binding Sites / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D020381:Interleukin-17 / Q000276:immunology / Q000378:metabolism*; D008958:Models, Molecular; D015394:Molecular Structure; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000378:metabolism*; D010077:Oxazepines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding / Q000187:drug effects; D013329:Structure-Activity Relationship; D058504:Th17 Cells / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism*
chemical_list: D020381:Interleukin-17; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D010077:Oxazepines
keywords: RORγ; TH17 cells; autoimmune diseases; cocrystal structures; interleukin 17 (IL-17); inverse agonists; nuclear receptors