Analytical evaluation of the automated interleukin-6 assay on the Roche cobas e602 analyzer

Area of Science:

• Clinical chemistry
• Immunology
• Biomarker validation

Background:

• Interleukin-6 (IL-6) is a key proinflammatory cytokine implicated in various inflammatory diseases.
• Accurate IL-6 measurement is crucial for disease monitoring and management.
• The Roche Elecsys IL-6 assay is an automated immunoassay with emergency use authorization.

Purpose of the Study:

• To evaluate the analytical performance of the automated Roche Elecsys IL-6 immunoassay.
• To assess the clinical performance of the Elecsys IL-6 assay by comparing it to a reference method.
• To determine the suitability of the assay for routine clinical use.

Main Methods:

• Precision, linearity, and interference studies were conducted for the Elecsys IL-6 assay.
• Analytical interference was assessed using hemoglobin, bilirubin, triglycerides, and biotin.
• Clinical performance was evaluated by comparing patient sample results with the V-PLEX Human IL-6 immunoassay.

Main Results:

• The Elecsys IL-6 assay demonstrated excellent precision (intra-assay CV <3%, interassay CV <5%) and a wide analytical range (1.5–4790 pg/mL).
• The assay showed tolerance to significant levels of common interferents.
• A systematic bias (slope bias of 2.95, mean difference of 152 pg/mL or 73%) was observed when compared to the V-PLEX assay.

Conclusions:

• The Roche Elecsys IL-6 assay exhibits robust analytical performance.
• A significant systematic bias between the Elecsys IL-6 and reference methods prevents interchangeable use for IL-6 monitoring.
• The automated, random-access nature of the Roche platform ensures IL-6 testing availability on demand.