title: Pharmacokinetic immunoassay methods in the presence of soluble target.
abstract: Soluble targets represent a special challenge when employing ligand binding assays to support pharmacokinetic analysis of monoclonal therapeutics. Target-engaged antibody is not available for binding in immunoassays employing anti-idiotype-specific antibodies or target for capture. We investigated several formats of total antibody assays that show reduced interference of soluble targets: direct target capture, indirect target capture and acid dissociation. While indirect target capture worked well for a regular affinity antibody against DKK1, a high affinity antibody against PCSK9 required an additional acid dissociation step. The choice of a suitable format was antibody and target dependent. Our results offer several choices to approach immunoassay development for soluble targets.
authors.affiliation: Merck & Co., Inc., 770 Sumneytown Pike, PO Box 4, West Point, PA 19486, USA. thorsten_verch@merck.com
authors.forename: Thorsten
authors.initials: T
authors.lastname: Verch
authors.forename: Shannon
authors.initials: S
authors.lastname: Chilewski
authors.forename: Silikhone
authors.initials: S
authors.lastname: Bouaraphan
authors.forename: Helen
authors.initials: H
authors.lastname: Yarovoi
authors.forename: Kuo-Chang
authors.initials: KC
authors.lastname: Yin
authors.forename: Dave
authors.initials: D
authors.lastname: Chen
authors.forename: Michael W
authors.initials: MW
authors.lastname: Washabaugh
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000494:pharmacology*; D000911:Antibodies, Monoclonal / Q000493:pharmacokinetics*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D036341:Intercellular Signaling Peptides and Proteins / Q000276:immunology; D000071449:Proprotein Convertase 9; D043484:Proprotein Convertases; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000276:immunology; D012697:Serine Endopeptidases / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D036341:Intercellular Signaling Peptides and Proteins; D000071449:Proprotein Convertase 9; D043484:Proprotein Convertases; D018719:Erb-b2 Receptor Tyrosine Kinases; D012697:Serine Endopeptidases; D014409:Tumor Necrosis Factor-alpha; C501126:DKK1 protein, human; C472125:PCSK9 protein, human