Access anti-HBc Total

The Access anti-HBc Total assay is a chemiluminescent immunoassay that detects total antibodies to hepatitis B virus core antigen (anti-HBc) in human serum and plasma samples from pediatric (2–21 years) and adult populations. It is intended as an aid in diagnosing acute, chronic, or resolved hepatitis B virus infection in individuals with signs/symptoms or risk factors, when used with other laboratory results and clinical information. The assay runs on the DxI 9000 Access Immunoassay Analyzer and is not intended for blood/tissue donor screening.

The candidate device uses a two-step competitive immunoassay with paramagnetic particles coated with HBc antigen, detected by automated chemiluminescence. Key differences from the ARCHITECT CORE predicate include: 105 µL sample volume (vs. 75 µL), ~36 minute result time (vs. ~29 minutes), 45-day on-board reagent stability (vs. 30 days), and 56-day calibration frequency (vs. 30 days). Both employ qualitative detection and liquid ready-to-use reagents, but run on different instruments (DxI 9000 vs. ARCHITECT i).

Studies were conducted using CLSI guidelines: EP05-A3 (imprecision), EP09c 3rd Edition (matrix equivalence), EP25-ED2 (stability), and EP10-A3 AMD (carryover). Analytical sensitivity was determined using the WHO 1st International Standard for Anti-HBc (NIBSC code 95/522).

The Access anti-HBc Total and ARCHITECT CORE both measure the same analyte (anti-HBc), employ similar two-step immunoassay operating principles with automated chemiluminescent detection, use qualitative reporting with comparable calibrators and controls, and are intended for the same clinical indications. Comprehensive analytical and clinical studies demonstrated 98.4% positive percent agreement and 98.9% negative percent agreement with the reference assay across 2,391 prospectively collected specimens, including pregnant and pediatric populations, supporting comparable safety and effectiveness.