Abstract Background Quantitative hepatitis B surface antigen (qHBsAg) assays are important tools for monitoring hepatitis B virus (HBV) infection and treatment response and constitute the primary endpoint in most HBV antiviral trials. To date, no qHBsAg assay has been authorized by the FDA for use in the United States, highlighting the need for performance evaluation and harmonization of available methods. Methods We evaluated the analytical performance of three commercial assays for qHBsAg measurement: Architect HBsAg Qualitative (Abbott) adapted for quantitative use, Elecsys HBsAg II quant II (Roche), and LIAISON XL Murex HBsAg Quant (DiaSorin). Performance characteristics including precision, accuracy, analytical sensitivity, linearity, and lot-to-lot variability were assessed using World Health Organization (WHO) International Standards 12/226 and 03/262, following CLSI guidelines. Clinical accuracy was also evaluated using 72 HBsAg-positive clinical specimens. Results The lower limit of quantification was 0.02 IU/mL for Architect, 0.07 IU/mL for Elecsys, and 1.02 IU/mL for LIAISON. The LIAISON exhibited limited linearity and significantly greater variability in samples with high HBsAg levels, as well as significant lot-to-lot variability. Ultimately, all three assays demonstrated acceptable precision and accuracy, though the LIAISON had to be recalibrated specifically with WHO International Standard 03/262. Conclusions The Architect and Elecsys qHBsAg assays demonstrated sufficient analytical performance for clinical use, while the LIAISON was limited by its linearity, lower limit of quantification, and lot-to-lot variability. Standardization is essential to ensure consistent and accurate quantification of HBsAg for effective clinical monitoring and the establishment of treatment goals.
Ko et al. (Tue,) studied this question.