title: General LC-MS/MS method approach to quantify therapeutic monoclonal antibodies using a common whole antibody internal standard with application to preclinical studies.
abstract: Ligand binding assays (LBAs) are widely used for therapeutic monoclonal antibody (mAb) quantification in biological samples. Major limitations are long method development times, reagent procurement, and matrix effects. LC-MS/MS methods using signature peptides are emerging as an alternative approach, which typically use a stable isotope labeled signature peptide as the internal standard (IS). However, a new IS has to be generated for every candidate, and the IS may not correct for variations at all processing steps. We have developed a general LC-MS/MS method approach employing a uniformly heavy-isotope labeled common whole mAb IS and a common immunocapture for sample processing. The method was streamlined with automation for consistency and throughput. Method qualification of four IgG(2) and four IgG(1) mAbs showed sensitivity of 0.1 μg/mL and linearity of 0.1-15 μg/mL. Quality control (QC) data of these eight mAbs were accurate and precise. The QC performance of the whole molecule labeled IS was better than those of synthetic labeled IS peptides tested. The pharmacokinetic results of two mAbs (an IgG(2) and IgG(1) candidate) dosed in rats were comparable to those of LBA. The general LC-MS/MS method approach overcomes the limitations of current methods to reduce time and resources required for preclinical studies.
authors.affiliation: PKDM, Amgen Inc., Thousand Oaks, California 91320, USA.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Li
authors.forename: Robert
authors.initials: R
authors.lastname: Ortiz
authors.forename: Linh
authors.initials: L
authors.lastname: Tran
authors.forename: Michael
authors.initials: M
authors.lastname: Hall
authors.forename: Chris
authors.initials: C
authors.lastname: Spahr
authors.forename: Ken
authors.initials: K
authors.lastname: Walker
authors.forename: John
authors.initials: J
authors.lastname: Laudemann
authors.forename: Sterling
authors.initials: S
authors.lastname: Miller
authors.forename: Hossein
authors.initials: H
authors.lastname: Salimi-Moosavi
authors.forename: Jean W
authors.initials: JW
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000032:analysis* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid / Q000592:standards; D004353:Drug Evaluation, Preclinical; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007553:Isotope Labeling; D010455:Peptides / Q000032:analysis; D011786:Quality Control; D012015:Reference Standards; D053719:Tandem Mass Spectrometry / Q000592:standards
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D010455:Peptides