Assessment of Viral Loads in Patients with Chronic Hepatitis C with AMPLICOR HCV MONITOR Version 1.0, COBAS HCV MONITOR Version 2.0, and QUANTIPLEX HCV RNA Version 2.0 Assays

Abstract

The correlation between response to antiviral therapy and pretreatment viral load in patients with chronic hepatitis C has prompted the development of quantitative assays to measure viral load. The aim of our study was to assess the clinical relevance of the newly developed semiautomated PCR system COBAS HCV MONITOR version 2.0 in comparison with (i) the AMPLICOR HCV MONITOR version 1.0 assay, which underestimates RNA concentration of hepatitis C virus (HCV) genotypes 2 to 6, and (ii) the QUANTIPLEX HCV RNA version 2.0 assay, which achieves equivalent quantification for each HCV genotype, with samples from 174 patients diagnosed with chronic hepatitis C before therapy. The level and range of quantification measured with AMPLICOR HCV MONITOR version 1.0 were 1 log lower than when measured with the COBAS HCV MONITOR version 2.0, at 0.261 × 106 RNA copies/ml (range, 0.001 × 106 to 2.50 × 106 RNA copies/ml) and 4.032 × 106 RNA copies/ml (range, 0.026 × 106 to 72.6 × 106 RNA copies/ml), respectively. The two assays showed a poor correlation (r 2 = 0.175). The level and range of quantification were similar when measured with the COBAS HCV MONITOR version 2.0 and QUANTIPLEX HCV RNA version 2.0 assays, at 3.03 × 106 RNA copies/ml (range, 0.023 × 106 to 72.6 × 106 RNA copies/ml) and 4.91 Meq/ml (range, 0.200 to 49.5 Meq/ml), respectively. The two assays showed a strong correlation (r 2 = 0.686) for each HCV genotype. The duration of treatment (6 or 12 months) is modulated according to HCV genotype and viral load. Our results indicate that COBAS HCV MONITOR version 2.0 and QUANTIPLEX HCV RNA version 2.0 assays showing an equal dynamic range for each HCV genotype are suitable tools to assess patients before therapy.

Evaluation of clinical usefulness of second‐generation HCV core antigen assay: comparison with COBAS AMPLICOR HCV MONITOR assay version 2.0

“…As shown in the present study, 204 (95.8%) of 213 cases were detectable by the second-generation assay, providing evidence that sensitivity was indeed significantly improved. The sensitivity of this assay was comparable with that of the COBAS v2.0 assay, a well-calibrated, sensitive and non-serotype-dependent assay (8,(17)(18)(19)(20)(24)(25)(26).…”

“…The quantification of HCV has become an important issue because low viral load is a strong predictor of sustained response to interferon (IFN) monotherapy for chronic hepatitis C (13-15). Among the assays for quantification of HCV load, combined reverse transcription PCR assay, the AM-PLICOR HCV MONITOR assay version 2.0 (CO-BAS v2.0) (Roche Molecular Systems, Branchburg, NJ), is now one of the most sensitive and reliable assays (16)(17)(18)(19)(20).…”

Molecular Analysis and Ex Vivo Infectivity of Seronegative Occult Hepatitis C Virus: A Study in Single Haemodialysis Centre

“…However, the quantification of anti-genomic strands does not represent the actual viral load in a sample; therefore, genomic strand copy numbers should be used for viral load determination. A viral load of less than 6.3 log 10 RNA copies/mL was considered low ( 23 ) and, based on the cut-off point value, viral loads in the PBMCs of patients with OCI were generally lower than those of patients with CCI. A low viral load usually indicates a better prognosis.…”

Comparative Evaluation of the VERSANT HCV RNA 3.0, QUANTIPLEX HCV RNA 2.0, and COBAS AMPLICOR HCV MONITOR Version 2.0 Assays for Quantification of Hepatitis C Virus RNA in Serum

“…There have been numerous studies demonstrating the shortcomings of the first generation of commercially available assays for the quantification of HCV. In particular, the inability of the AMPLICOR HCV MONITOR test version 1.0 (Roche Diagnostics Corporation) and the QUANTIPLEX HCV RNA 1.0 assay (Chiron Corporation, Emeryville, Calif.) to quantify HCV RNA from HCV genotypes 1 to 6 equally has been well documented (5,8,12,14). The shortcomings of these early quantitative assays made the task of accurately assessing the influence of HCV viral load and genotype on disease outcome a complex task.…”

“…While many of the problems associated with the first-generation branched DNA (bDNA) and reverse transcription-PCR assays have reportedly been resolved (5,8,10,12,14,19), the issue of standardization of test reporting has only recently been addressed with the establishment of the World Health Organization (WHO) HCV international unit. The HCV interna-tional unit is a standardized unit of measure established by the WHO based on the consensus value obtained from the quantitative analysis of a single HCV RNA sample by numerous participating laboratories throughout the world (18).…”