Performance Characteristics of a Quantitative TaqMan Hepatitis C Virus RNA Analyte-Specific Reagent

Abstract

We determined the dynamic range, reproducibility, accuracy, genotype bias, and sensitivity of the TaqMan hepatitis C virus (HCV) analyte-specific reagent (ASR). Serum samples were processed using the MagNA Pure LC instrument and run on the COBAS TaqMan Both qualitative and quantitative hepatitis C virus (HCV) RNA tests are used in diagnosis and management of patients with hepatitis C, because no single commercially available test combines high analytical sensitivity with a broad dynamic range. Qualitative nucleic acid amplification tests for detection of HCV RNA in serum are used to confirm the diagnosis of hepatitis C, distinguish active from resolved infection, assess virological response to therapy, and screen blood donors (3,18,23). Quantitative tests are used in evaluation of patients being considered for therapy and to assess early response to therapy. A pretreatment viral load of less than 800,000 IU/ml is one of several predictors of a sustained virological response (20,24). Viral load testing has also been used in early assessment of treatment response. Patients who fail to achieve at least a 2-log 10 decline in viral load after 12 weeks of treatment have little chance of a sustained response and can be spared the cost and toxicity of a complete treatment course (9, 17). However, viral load does not predict the progression of hepatitis C and is not associated with the severity of liver disease.A variety of tests for detection and quantitation of HCV RNA based on different nucleic acid amplification technologies are commercially available. The qualitative AMPLICOR HCV and quantitative AMPLICOR HCV MONITOR version 2.0 tests (Roche Diagnostics Corporation, Indianapolis, Ind.) are based on conventional reverse transcription-PCR in a heterogeneous format (17). The VERSANT HCV RNA qualitative and VERSANT HCV RNA 3.0 quantitative assays (Bayer Healthcare, Tarrytown, N.Y.) are based on transcription-mediated amplification and branched DNA signal amplification, respectively (10, 15).These tests also differ in their lower limits of detection and dynamic ranges. The qualitative AMPLICOR and VERSANT tests have lower limits of detection of 50 and 5 IU/ml, respectively. Although the lower limits of detection for the quantitative AMPLICOR and VERSANT tests are both approximately 600 IU/ml, the dynamic ranges differ by approximately 1 log 10 and are 3.1 and 4.1 log 10 , respectively. Because of the differences in sensitivity between the qualitative and quantitative assays, many clinical laboratories use a quantitative test to determine viral load and a sensitive qualitative test for diagnosis and test-of-cure. A single test with sensitivity similar to the qualitative tests that accurately quantitates high viral loads would be beneficial for clinical laboratories.A number of homogeneous TaqMan reverse transcription-PCR assays for detection and quantitation of HCV RNA have been described (12,13,19,21,29). These tests are very sensitive, have broad dynamic ranges, and provide precise quantitation of viral load. These tes...

HCV RNA detection by TMA during the hepatitis C antiviral long-term treatment against cirrhosis (Halt-C) trial

“…1,2 Recently, several assays with greater sensitivity, having a limit of 5-10 IU/mL or less, have become available. [7][8][9][10] One of these tests, the Bayer VERSANT HCV RNA Qualitative Assay, based on transcription-mediated amplification (TMA) technology, has been approved by the U.S. Food and Drug Administration for detection of HCV RNA as evidence of active infection. The usefulness and potential role of this assay in monitoring the course and outcome of therapy for hepatitis C has yet to be fully defined.…”

Merimepodib, pegylated interferon, and ribavirin in genotype 1 chronic hepatitis C pegylated interferon and ribavirin nonresponders

“…Antiviral response was assessed by plasma HCV RNA testing using the COBAS TaqMan HCV test (TaqMan HCV; Roche Molecular Systems, Branchburg, NJ). 11 The lower limit of quantification and the limit of detection for this HCV RNA assay were 30 IU/mL and 10 IU/mL, respectively. Additional plasma and serum samples were collected at several study visits to assess the PK parameters of MMPD and RBV.…”

Evaluation of the Performance Characteristics of an In-House One Step TaqMan Real Time-Polymerase Chain Reaction Assay for Detection and Quantification of Hepatitis C Virus

“…Patients with viral load less than 600,000 IU/mL and those with HCV genotype 2 or 3, have higher sustained virological response rates (3). At least 2 log 10 unit decrease in HCV RNA viral load compared to the initial level of HCV RNA level after 12 weeks of treatment, indicates early virological response (4,5).…”