Multicenter Evaluation of the Performance Characteristics of the Bayer VERSANT HCV RNA 3.0 Assay (bDNA)

Abstract

In this multicenter evaluation, the VERSANT HCV RNA 3.0 Assay (bDNA) (Bayer Diagnostics, Tarrytown, N.Y.) was shown to have excellent reproducibility, linearity, and analytical sensitivity across specimen collection matrices (serum, EDTA, ACD-A), and hepatitis C virus (HCV) genotypes 1 to 6. The VERSANT HCV bDNA Assay has a reportable range of 615 to 7,690,000 (7.69 ؋ 10 6 ) IU/ml. The total coefficient of variation (CV) ranged from 32.4% at 615 IU/ml to 17% at 6.8 ؋ 10 6 IU/ml. The assay was linear across the reportable range. Analytical specificity of 98.8% was determined by testing 999 specimens from volunteer blood donors. Evaluation of HCV genotypes using RNA transcripts of representative clones of 1a, 1b, 2a, 2b, 2c, 3a, 4a, 5a, and 6a and patient specimens showed that the largest difference between genotype 1, upon which the assay is standardized, and non-1 genotypes was within 1.5-fold. Testing of potentially interfering endogenous substances and exogenous substances and conditions found no interference in HCV-positive or HCV-negative specimens except for unconjugated bilirubin at concentrations of >20 mg/dl and protein at concentrations of >9 g/dl. Biological variability was estimated from 29 clinically stable individuals not on HCV therapy who were tested weekly over an 8-week period. The combined estimate of total (biologic plus assay) variability was 0.15 log 10 standard deviation (CV, 36.1%), a fold change of 2.6. Thus, the observed fold change between any two consecutive HCV RNA measures is expected to be less than 2.6-fold (equivalent to 0.41 log 10 IU/ml) 95% of the time in clinically stable individuals.Hepatitis C virus (HCV) infection is a major health care problem, with an estimated 4 million individuals infected in the United States (1) and 170 million infected worldwide (26). Approximately 70% of those infected will develop chronic HCV infection, which is a leading cause of chronic liver disease (13). Interferon monotherapy was the first antiviral regimen approved for treatment of chronic HCV infection. Sustained response rates were low (8 to 12%) (3), but newer antiviral treatments (interferon plus ribavirin, peginterferon plus ribavirin) have improved the response rates, particularly for patients infected with non-1 genotypes.Quantitative HCV RNA results have been used prior to initiating interferon-based anti-HCV treatment to assess the likelihood of sustained virological response, defined as a negative result in a qualitative HCV RNA assay 6 months after the end of treatment. HCV RNA levels or changes from baseline have also been used early in treatment to attempt to accurately predict response to treatment (6,10,14,15,18,20,27).The performance characteristics of an assay, i.e., its accuracy, reproducibility, and predictive values, determine the interpretation and utility of the assay's results (12, 18). The VERSANT HCV bDNA Assay, utilizing a signal amplification technique, is a fundamentally simple hybridization-based procedure involving unique nucleic acid probes directed to highly co...

Comparison of Qualitative (COBAS AMPLICOR HCV 2.0 versus VERSANT HCV RNA) and Quantitative (COBAS AMPLICOR HCV Monitor 2.0 versus VERSANT HCV RNA 3.0) Assays for Hepatitis C Virus (HCV) RNA Detection and Quantification: Impact on Diagnosis and Treatment of HCV Infections

“…The specificity, reproducibility, sensitivity, and linear range of quantification of the HCV bDNA 3.0 assay were described in detail by Ross et al (31). The lowest concentration of HCV RNA that produces a quantitative result in 95% of replicate specimens (95% detection limit) was found to be 990 IU/ml (10).…”

Performance of the Abbott Real-Time PCR Assay Using m 2000 sp and m 2000 rt for Hepatitis C Virus RNA Quantification

“…The bDNA assay can be confidently used as a comparator, since it has been shown to be precise and accurate and to equally quantify HCV genotypes 1 to 6, due to the use of a set of 6 capture and 17 extender oligonucleotide probes spanning the full-length 5Ј-noncoding region and the 5Ј third of the core coding region for hybridization of the HCV genome (1,8,9,12,13,(17)(18)(19)24).…”

Comparison of Conventional PCR with Real-Time PCR and Branched DNA-Based Assays for Hepatitis C Virus RNA Quantification and Clinical Significance for Genotypes 1 to 5

“…Furthermore, for assessment of virologic response to currently developed direct antiviral drugs (i.e., protease and polymerase inhibitors), proper HCV RNA quantification for the different HCV genotypes is critical (1,14,25,26). WHO HCV international standard, 96/790 (2,7,11,17,23,24,27). However, continuing limitations are the lack of complete automation (22), the necessity for dilutions for quantification by standard PCR-based assays (6), the relatively low sensitivity of quantitative HCV RNA assays (31), and the need for different test systems for qualitative and quantitative HCV RNA measurements (31).…”