title: Commercial biomarker assays: friend and foe.
abstract: OBJECTIVE
  Commercial kits can provide a convenient solution for measuring circulating biomarkers to support drug development. However, their suitability should be assessed in the disease matrix of interest.
  
  
  METHODS
  Twelve biomarkers were evaluated in samples from patients with rheumatoid arthritis. We used immunoassay kits from five vendors on three multiplexed platforms. Kit suitability was evaluated on the basis of detectability and prespecified performance acceptance criteria.
  
  
  RESULTS
  Assays had varying levels of sensitivity and susceptibility to interference by matrix components. Only a few assays in the multiplexed kits were found to be suitable. In general, kits for analytes that passed our assay criteria showed good correlation between vendors.
  
  
  CONCLUSIONS
  The data from this study demonstrate that the majority of assays on multiplexed kits evaluated either lacked sensitivity and/or had poor performance, which diminishes the utility of the multiplexing approach.
authors.affiliation: Department of BioAnalytical Sciences, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Saloumeh K
authors.initials: SK
authors.lastname: Fischer
authors.affiliation: Department of BioAnalytical Sciences, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Carrasco-Triguero
authors.affiliation: Department of BioAnalytical Sciences, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Kyu
authors.initials: K
authors.lastname: Hong
authors.affiliation: Department of BioAnalytical Sciences, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Good
authors.affiliation: Department of BioAnalytical Sciences, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Teresa
authors.initials: T
authors.lastname: Davancaze
authors.affiliation: Department of BioAnalytical Sciences, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Trung
authors.initials: T
authors.lastname: Nguy
authors.affiliation: Department of Oncology Biomarker Development, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Oncology Biomarker Development, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Walter
authors.initials: W
authors.lastname: Darbonne
authors.affiliation: Department of OMNI (Ophthalmology, Metabolism, Neurology, Immunology) - BD (Biomarker Development), Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Alyssa
authors.initials: A
authors.lastname: Morimoto
authors.affiliation: Department of Biostatistics, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
authors.forename: Yuda
authors.initials: Y
authors.lastname: Zhu
keywords: Aushon; CyPlex (SimplePlex); Luminex; biomarkers; commercial kits; detectability; heterophilic antibody; immunoassay; multiplexing