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bioRxiv · 10.1101/2020.10.14.340398

Performances of NeuMoDx, a random-access system for HBV-DNA and HCV-RNA quantification

Besombes, J.·Pronier, C.·Lefevre, C.·Lagathu, G.·Maillard, A.·Grolhier, C.·Thibault, V.
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Abstract

Viral loads (VL) monitoring for hepatitis B and C is essential to evaluate disease progression and treatment response. Automated, random-access rapid systems are becoming standard to provide reliable VL to clinicians. The aim of this study was to evaluate the analytical performances of the recently launched NeuMoDx for HBV-DNA and HCV-RNA quantification. 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=124) tested using NeuMoDx. Linearity range was assessed on serial dilutions of high tittered plasmas containing different genotypes for HBV (A-E, n=10) and HCV (1a-b, 2-5, n=12). Overall test failure, mostly internal control amplification failure, was 2.3% and was not influenced by matrix types. For HBV-VL, Kappa 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, Kappa 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 HBV and HCV genotypes. The mean turnaround time was 72 [55-101] for HBV and 96 [78-133] for HCV. These 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.

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Besombes, J., Pronier, C., Lefevre, C., Lagathu, G., Maillard, A., Grolhier, C., Thibault, V.. 2020-10-16. Performances of NeuMoDx, a random-access system for HBV-DNA and HCV-RNA quantification. https://doi.org/10.1101/2020.10.14.340398

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