title: Recommendations for the bioanalytical method validation of ligand-binding assays to support pharmacokinetic assessments of macromolecules.
abstract: OBJECTIVE
  With this publication a subcommittee of the AAPS Ligand Binding Assay Bioanalytical Focus Group (LBABFG) makes recommendations for the development, validation, and implementation of ligand binding assays (LBAs) that are intended to support pharmacokinetic and toxicokinetic assessments of macromolecules.
  
  
  METHODS
  This subcommittee was comprised of 10 members representing Pharmaceutical, Biotechnology, and the contract research organization industries from the United States, Canada, and Europe. Each section of this consensus document addresses a specific analytical performance characteristic or aspect for validation of a LBA. Within each section the topics are organized by an assay's life cycle, the development phase, pre-study validation, and in-study validation. Because unique issues often accompany bioanalytical assays for macromolecules, this document should be viewed as a guide for designing and conducting the validation of ligand binding assays.
  
  
  RESULTS
  Values of +/- 20% (25% at the lower limit of quantification [LLOQ]) are recommended as default acceptance criteria for accuracy (% relative error [RE], mean bias) and interbatch precision (%coefficient of variation [CV]). In addition, we propose as secondary criteria for method acceptance that the sum of the interbatch precision (%CV) and the absolute value of the mean bias (%RE) be less than or equal to 30%. This added criterion is recommended to help ensure that in-study runs of test samples will meet the proposed run acceptance criteria of 4-6-30. Exceptions to the proposed process and acceptance criteria are appropriate when accompanied by a sound scientific rationale.
  
  
  CONCLUSIONS
  In this consensus document, we attempt to make recommendations that are based on bioanalytical best practices and statistical thinking for development and validation of LBAs.
authors.affiliation: Amgen Inc, Thousand Oaks, California, USA.
authors.forename: Binodh
authors.initials: B
authors.lastname: DeSilva
authors.forename: Wendell
authors.initials: W
authors.lastname: Smith
authors.forename: Russell
authors.initials: R
authors.lastname: Weiner
authors.forename: Marian
authors.initials: M
authors.lastname: Kelley
authors.forename: JoMarie
authors.initials: J
authors.lastname: Smolec
authors.forename: Ben
authors.initials: B
authors.lastname: Lee
authors.forename: Masood
authors.initials: M
authors.lastname: Khan
authors.forename: Richard
authors.initials: R
authors.lastname: Tacey
authors.forename: Howard
authors.initials: H
authors.lastname: Hill
authors.forename: Abbie
authors.initials: A
authors.lastname: Celniker
mesh_terms: D002352:Carrier Proteins / Q000378:metabolism; D008024:Ligands; D046911:Macromolecular Substances; D004364:Pharmaceutical Preparations / Q000378:metabolism / Q000592:standards*; D011869:Radioligand Assay / Q000592:standards*; D015203:Reproducibility of Results
chemical_list: D002352:Carrier Proteins; D008024:Ligands; D046911:Macromolecular Substances; D004364:Pharmaceutical Preparations