Comprehensive comparison of the VERSANT ® HIV-1 RNA 3.0 (bDNA) and COBAS AMPLICOR HIV-1 MONITOR ® 1.5 assays on 1000 clinical specimens

• Published in: Journal of clinical virology 2005-12, Vol.34 (4), p.245-252
• Main Authors: Galli, Rick, Merrick, Linda, Friesenhahn, Michel, Ziermann, Rainer
• Format: Article
• Language: English
• Subjects: bDNA; HIV-1 RNA; Patient management; PCR; Viral load
• ISSN: 1386-6532; 1873-5967
• DOI: 10.1016/j.jcv.2004.12.012

Plasma human immunodeficiency virus type 1 (HIV-1) RNA level is an important parameter for patient management, yet viral load assays from different manufacturers are not standardized. In this study, we evaluated the concordance between test results obtained for 1000 plasma specimens collected from HIV-1-infected individuals measured with the VERSANT ® HIV-1 RNA 3.0 assay (bDNA) and the COBAS AMPLICOR HIV-1 MONITOR ® 1.5 test (PCR). We compared viral load values obtained by each of these assays throughout their dynamic ranges, with particular focus on samples with low viral load (i.e. 50–250 copies/mL), and calculated the estimated distribution of distinct plasma viral load levels for the entire study population modeled from the data observed in the study. We found that these two assays show excellent agreement, with a correlation ( R 2) of 0.957 and a slope of 1.004. The mean difference in viral load values between the two assays was less than 0.10-log 10 throughout the dynamic range and 98.2% of all samples had bDNA and PCR results within 0.5-log 10 of each other, a difference that is within the range considered to be a minimal change in plasma viremia. Moreover, the two assays show very similar results across all assay ranges tested. The estimated prevalence of samples with results