Performances of NeuMoDx™, a random-access system for hepatitis B virus DNA and hepatitis C virus RNA quantification

Abstract

Objective: Monitoring of viral loads (VL) for hepatitis B and C viruses (HBV; HCV) is essential to evaluate disease progression and treatment response. Automated, random-access rapid systems are becoming standard to provide clinicians with reliable VL. The aim of this study was to evaluate the analytical performances of the recently launched NeuMoDx™ for HBV-DNA and HCV-RNA quantification.

Methods: Clinical samples routinely quantified on the Beckman-Veris system were either retrospectively (frozen samples; HBV n = 178, HCV n = 249), or in parallel (fresh primary tubes; HBV n = 103, HCV n = 117) tested using NeuMoDx™. Linearity range was assessed on serial dilutions of high-titre plasmas containing different genotypes for HBV (A-E, n = 9) and HCV (1a,1b,2-5, n = 12).

Results: Overall test failure, mostly internal control amplification failure, was 2.3% and was not influenced by matrix types (fresh or frozen). For HBV VL, κ agreement was 74%, with 27 (12.6%) discrepancies. Correlation between HBV assays on 72 quantified samples by both methods was excellent (r = 0.963) with a mean bias (NeuMoDx™-Veris) of 0.21 log IU/mL. For HCV VL, κ agreement reached 94%, with 9 (2.8%) discrepancies. The r correlation factor between assays on 104 samples was 0.960 with a mean bias of -0.14 log IU/mL (NeuMoDx™-Veris). Serial dilutions confirmed the claimed linear ranges for all analysed HBV and HCV genotypes. The mean turnaround time was 72 minutes (range 55-101 minutes) for HBV and 96 minutes (range 78-133 minutes) for HCV.

Conclusion: Results obtained on the NeuMoDx™ confirmed the overall good functionality of the system with a short turn-around-time, full traceability and easy handling. These results on HBV and HCV VL look promising and should be challenged with further comparisons.

Keywords: Correlation analysis; Hepatitis; Molecular biology; Viral load.