Commercial biomarker assays: friend and foe.

Aim: 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. Methodology: 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. Conclusion: 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.