title: Evaluation of JAK3 Biology in Autoimmune Disease Using a Highly Selective, Irreversible JAK3 Inhibitor.
abstract: Reversible janus associated kinase (JAK) inhibitors such as tofacitinib and decernotinib block cytokine signaling and are efficacious in treating autoimmune diseases. However, therapeutic doses are limited due to inhibition of other JAK/signal transducer and activator of transcription pathways associated with hematopoiesis, lipid biogenesis, infection, and immune responses. A selective JAK3 inhibitor may have a better therapeutic index; however, until recently, no compounds have been described that maintain JAK3 selectivity in cells, as well as against the kinome, with good physicochemical properties to test the JAK3 hypothesis in vivo. To quantify the biochemical basis for JAK isozyme selectivity, we determined that the apparentKmvalue for each JAK isozyme ranged from 31.8 to 2.9μM for JAK1 and JAK3, respectively. To confirm compound activity in cells, we developed a novel enzyme complementation assay that read activity of single JAK isozymes in a cellular context. Reversible JAK3 inhibitors cannot achieve sufficient selectivity against other isozymes in the cellular context due to inherent differences in enzyme ATPKmvalues. Therefore, we developed irreversible JAK3 compounds that are potent and highly selective in vitro in cells and against the kinome. Compound 2, a potent inhibitor of JAK3 (0.15 nM) was 4300-fold selective for JAK3 over JAK1 in enzyme assays, 67-fold [interleukin (IL)-2 versus IL-6] or 140-fold [IL-2 versus erythropoietin or granulocyte-macrophage colony-stimulating factor (GMCSF)] selective in cellular reporter assays and >35-fold selective in human peripheral blood mononuclear cell assays (IL-7 versus IL-6 or GMCSF). In vivo, selective JAK3 inhibition was sufficient to block the development of inflammation in a rat model of rheumatoid arthritis, while sparing hematopoiesis.
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Fiona
authors.initials: F
authors.lastname: Elwood
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: David J
authors.initials: DJ
authors.lastname: Witter
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Piesvaux
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Brian
authors.initials: B
authors.lastname: Kraybill
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Nathan
authors.initials: N
authors.lastname: Bays
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Carla
authors.initials: C
authors.lastname: Alpert
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Peter
authors.initials: P
authors.lastname: Goldenblatt
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Qu
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Irena
authors.initials: I
authors.lastname: Ivanovska
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Hyun-Hee
authors.initials: HH
authors.lastname: Lee
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Chi-Sung
authors.initials: CS
authors.lastname: Chiu
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Hao
authors.initials: H
authors.lastname: Tang
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Scott
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Sujal V
authors.initials: SV
authors.lastname: Deshmukh
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Mark
authors.initials: M
authors.lastname: Zielstorff
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Alan
authors.initials: A
authors.lastname: Byford
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Kalyan
authors.initials: K
authors.lastname: Chakravarthy
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Lauren
authors.initials: L
authors.lastname: Dorosh
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Alexey
authors.initials: A
authors.lastname: Rivkin
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Joel
authors.initials: J
authors.lastname: Klappenbach
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Bo-Sheng
authors.initials: BS
authors.lastname: Pan
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Ilona
authors.initials: I
authors.lastname: Kariv
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Christopher
authors.initials: C
authors.lastname: Dinsmore
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts.
authors.forename: Deborah
authors.initials: D
authors.lastname: Slipetz
authors.affiliation: Departments of Respiratory and Immunology (F.E., Y.Q., I.I., H.-H.L., H.T., D.S.), Chemistry (D.W., M.E.S., A.R., C.D.), Pharmacology (J.P., B.K., N.B., C.A., P.G., M.Z., A.B., K.C., B.-S.P., I.K., P.J.D.), and Pharmacokinetics, Pharmacodynamics and Drug Metabolism (C.-S.C., S.V.D., L.D., J.K.), Merck Research Laboratories, Boston, Massachusetts peter.dandliker@merck.com.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Dandliker
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental / Q000188:drug therapy; D001327:Autoimmune Diseases / Q000188:drug therapy / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016903:Drug Monitoring / Q000379:methods; D006801:Humans; D007527:Isoenzymes; D053613:Janus Kinase 1 / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D053616:Janus Kinase 3 / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D015166:Monitoring, Immunologic / Q000379:methods; D010880:Piperidines / Q000494:pharmacology*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology*; D011758:Pyrroles / Q000494:pharmacology*; D051381:Rats
chemical_list: D007527:Isoenzymes; D010880:Piperidines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D011758:Pyrroles; C479163:tofacitinib; D053613:Janus Kinase 1; D053616:Janus Kinase 3