title: Multiple compound-related adverse properties contribute to liver injury caused by endothelin receptor antagonists.
abstract: Drug-induced liver injury has been observed in patients treated with the endothelin receptor antagonists sitaxentan and bosentan, but not following treatment with ambrisentan. The aim of our studies was to assess the possible role of multiple contributory mechanisms in this clinically relevant toxicity. Inhibition of the bile salt export pump (BSEP) and multidrug resistance-associated protein 2 was quantified using membrane vesicle assays. Inhibition of mitochondrial respiration in human liver-derived HuH-7 cells was determined using a Seahorse XF(e96) analyzer. Cytochrome P450 (P450)-independent and P450-mediated cell toxicity was assessed using transfected SV40-T-antigen-immortalized human liver epithelial (THLE) cell lines. Exposure-adjusted assay ratios were calculated by dividing the maximum human drug plasma concentrations by the IC50 or EC50 values obtained in vitro. Covalent binding (CVB) of radiolabeled drugs to human hepatocytes was quantified, and CVB body burdens were calculated by adjusting CVB values for fractional drug turnover in vitro and daily therapeutic dose. Sitaxentan exhibited positive exposure-adjusted signals in all five in vitro assays and a high CVB body burden. Bosentan exhibited a positive exposure-adjusted signal in one assay (BSEP inhibition) and a moderate CVB body burden. Ambrisentan exhibited no positive exposure-adjusted assay signals and a low CVB body burden. These data indicate that multiple mechanisms contribute to the rare, but potentially severe liver injury caused by sitaxentan in humans; provide a plausible rationale for the markedly lower propensity of bosentan to cause liver injury; and highlight the relative safety of ambrisentan.
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: J Gerry
authors.initials: JG
authors.lastname: Kenna
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Simone H
authors.initials: SH
authors.lastname: Stahl
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Eakins
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Alison J
authors.initials: AJ
authors.lastname: Foster
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Linda C
authors.initials: LC
authors.lastname: Andersson
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Bergare
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Martin
authors.initials: M
authors.lastname: Billger
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Elebring
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden.
authors.forename: Charles S
authors.initials: CS
authors.lastname: Elmore
authors.affiliation: Drug Safety Consultant, Macclesfield, Cheshire, United Kingdom (J.G.K.); DMPK (S.H.S.), Discovery Safety (J.A.E.), and Translational Safety (A.J.F.), Drug Safety and Metabolism, AstraZeneca R&D Alderley Park, Macclesfield, Cheshire, United Kingdom; DMPK (L.C.A., J.B., C.S.E.), Regulatory Safety (M.B.), Drug Safety and Metabolism, AstraZeneca R&D Mölndal, Mölndal, Sweden; and DMPK, Cardiovascular and Metabolic Diseases (M.E.), and Respiratory, Inflammation, and Autoimmunity (R.A.T.), iMED AstraZeneca R&D Mölndal, Mölndal, Sweden richard.thompson@astrazeneca.com.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Thompson
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000037:antagonists & inhibitors; D000074020:ATP Binding Cassette Transporter, Subfamily B, Member 11; D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors; D000077300:Bosentan; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D056486:Chemical and Drug Induced Liver Injury / Q000209:etiology* / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D065128:Endothelin Receptor Antagonists / Q000493:pharmacokinetics / Q000633:toxicity*; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D022781:Hepatocytes / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007555:Isoxazoles / Q000493:pharmacokinetics / Q000633:toxicity*; D008928:Mitochondria / Q000378:metabolism; D015394:Molecular Structure; D010101:Oxygen Consumption / Q000502:physiology; D010666:Phenylpropionates / Q000493:pharmacokinetics / Q000633:toxicity*; D011724:Pyridazines / Q000493:pharmacokinetics / Q000633:toxicity*; D013449:Sulfonamides / Q000493:pharmacokinetics / Q000633:toxicity*; D013876:Thiophenes / Q000493:pharmacokinetics / Q000633:toxicity*; D000097202:ATP-Binding Cassette Sub-Family B Member 4
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000074020:ATP Binding Cassette Transporter, Subfamily B, Member 11; D018528:ATP-Binding Cassette Transporters; D000077300:Bosentan; D003577:Cytochrome P-450 Enzyme System; D065128:Endothelin Receptor Antagonists; D007555:Isoxazoles; D010666:Phenylpropionates; D011724:Pyridazines; D013449:Sulfonamides; D013876:Thiophenes; D000097202:ATP-Binding Cassette Sub-Family B Member 4; C093491:ABCB11 protein, human; C467894:ambrisentan; C106276:sitaxsentan