Evaluation of the Versant ? HBV DNA 3.0 Assay (bDNA)+ and comparison with the Cobastm HBV Taqman Analyte Specific Reagent Assay.

PosterTo evaluate the performance characteristics of the Versant ? HBV DNA 3.0 assay (bDNA)+ (Versant, Bayer Healthcare LLC, Tarrytown, NY). 2.) To compare the Versant assay to the COBAS HBV TaqMan Analyte Specific Reagent assay (TaqMan) (Roche Molecular Systems, Pleasanton, CA) using random and defined patient populations

Performance characteristics of the COBAS HCV TaqMan ASR and Comparison to the COBAS Amplicor HCV Monitor, Version 2.0 and Versant HCV bDNA 3.0.

PosterEvaluate the COBAS HCV TaqMan ASR assay using both the Qiagen BioRobot 9604 and a 1mL extraction protocol for HCV RNA isolation. And Compare the COBAS TaqMan HCV ASR assay to the COBAS Amplicor HCV Monitor, Version 2.0 and Versant HCV bDNA 3.0 assays

Performance Characteristics of the COBAS HCV TaqMan ASR Using Armored RNA Calibrators

PosterAs improved therapies have become available for Hepatititis C Virus (HCV) infection, the use of assays to quantitate HCV RNA has increased dramatically (3, 14, 16). The initial use of these assays was to predict the likelihood of therapy based on baseline HCV RNA levels. These reports indicated that HCV RNA levels >2,000,000 HCV RNA copies/mL were indicative of a decreased response to therapy. Other studies have suggested that the presence or absence of HCV RNA at a particular time point during therapy is predictive of relapse (5, 18). Recent data, including that from pegylated interferon treatment studies (2, 4, 6, 7, 17), have provided additional incentive for HCV RNA quantitative monitoring. This work suggests that quantitative HCV testing can be used to identify patients for whom HCV viral load does not decrease greater than 2 logs during the first 12 weeks of treatment. Such patients are found to have a high likelihood of treatment failure(1, 4, 12, 19)

Comparison of the National Genetics Institute (NGI) HCV Superquant and Roche COBAS Amplicor HCV Monitor, Version 2.0 Assays

PosterChronic Hepatitis C infection is currently recognized as an important health care problem. It is estimated that nearly 4 million Americans are infected, 15 to 20 percent of whom will eventually develop Cirrhosis. Current treatments for Hepatitis C virus (HCV) are limited to alfa-interferon alone or in combination therapy with Ribavirin. Quantitation of HCV RNA in patient samples has become a valuable tool in the evaluation of patients undergoing therapy and has been used as a measure of response to treatment. Three recent studies (Poynard, Davis, McHutchinson) investigating the effectiveness of alfa-interferon and Ribavirin therapy have used HCV RNA viral loads as a marker for treatment efficacy

Evaluation of the COBAS HBV TaqMan Analyte Specific Regent (ASR) Assay and Comparison to the COBAS Amplicor HBV Monitor Assay.

Postererformance characteristics of the COBAS HBV TaqMan ASR (TaqMan) assay were evaluated and compared to the COBAS Amplicor HBV Monitor test (Amplicor) assay for the quantification of HBV DNA in clinical samples

Comparison of the DIGENE HBV HYBRID CAPTURE II AND ROCHE COBAS Amplicor HBV Monitor Assays.

PosterEvaluate and compare the performance characteristics of the COBAS Amplicor HBV Monitor test (Roche Diagnostics Corp.) and the HBV Hybrid capture II (Digene Corporation) assay for the quantification of HBV BNA Levels

Evaluation of the COBAS HBV TaqMan Analyte Specific Regent (ASR) and COBAS HCV TaqMan ASR Assays using the Vidiera NSP sample preparation instrument.

PosterThe Vidiera Nsp nucleic sample preparation instrument (Vidiera,Beckman-Coulter Inc., Fullerton CA) was evaluated using the COBAS HBV TaqMan Analyte Specific Reagent (ASR. Roche Molecular Diagnostics [RMD], Indianapolis, IN) and COBAS HCV TaqMan ASR (RMD) assays using clinical samples and HCV Armored RNA

Evaluation of the Alliance HCV Quantitative Analyte Specific Reagent (ASR) Assay and Comparison to the COBAS HCV TaqMan ASR Assay.

PosterTo evaluate the Abbott/Celera Alliance HCV Quantitative ASR (Alliance) assay using the Qiagen BioRobot 9604 and QiaAmp Virus Kit for viral RNA isolation. And compare Alliance HCV TaqMan ASR to the Roche COBAS HCV TaqMan ASR (CTM) assay calibrated using Armored RNA solutions and WHO 2nd international standard Metods: To evaluate linearity, dilutions of an Armored RNA solution and high titer patient specimens assayed in the Alliance assay using the Qiagen 9604 BioRobot and QIAamp Virus BioRobot 9604 Kit for RNA extraction. A split sample study was conducted using one hundred forty clilnical samples previously assayed by CTM assay (calibrated directly to the 2nd WHO international standard, with results from 200 to 100.000,000 IU/mL) and tested in the Alliance assay. The results were analyzed using Deming regression. Ninety-two clinical samples previously tested in the CTM assay with result <200 IU/mL were randomly selected and tested in the Alliance assay to determine the number of samples were measurable HCV RNA status. Within-run linearity was evaluated using replicated date from the linerity studies and between-run precisoion was estimated from control material replicated

Evaluation of the COBAS Amplicor HBV Monitor Assay and Comparison with the Ultrasensitive HBV Hybrid Capture 2 Assay for Quantification of Hepatitis B Virus DNA

Performance characteristics of the COBAS Amplicor HBV Monitor test (Roche Diagnostics), which measures hepatitis B virus (HBV) DNA quantitatively, were evaluated and compared with the Ultrasensitive HBV Hybrid Capture 2 (HC2; Digene Corporation) assay. Linearity and within-run precision were assessed for both methods by using eight HBV DNA-positive samples serially diluted to obtain a range of <100 to 500,000 HBV DNA copies/ml and run in triplicate. Agreement between the methods was studied with 100 clinical samples. HC2 assay performance near the limit of detection was investigated through repeat testing of 149 samples with HC2 and testing of 37 samples with HC2 results of <4,700 HBV DNA copies/ml by Amplicor assay and a qualitative PCR assay. The linearity experiment for Amplicor had regression of observed values compared to expected values (y = 1.073x − 0.247; R(2) = 0.993, n = 32; for HC2, y = 0.855x + 0.759, R(2) = 0.729, n = 18). Within-run standard deviation of log HBV DNA copies/ml ranged from 0.003 to 0.348 (Amplicor) and 0.027 to 0.253 (HC2). Agreement assessed by Deming regression was poor [Amplicor = 1.197(HC2) − 0.961; R(2) = 0.799, standard error of the estimate (SEE) = 0.710, n = 94]. Near the lower limit of detection, 32 of 149 repeat HC2 results were <4,700 HBV DNA copies/ml. Of the 37 samples with HC2 results of <4,700 HBV DNA copies/ml, HBV DNA was not detected in 15 samples, while HBV DNA was detected by at least one PCR method in 12 samples. Amplicor is linear from 200 to 200,000 HBV DNA copies/ml with undiluted samples, and this range can be expanded through dilution. Inconsistent HC2 results near the limit of detection justify use of a grey zone

Performance Characteristics of the COBAS Amplicor Hepatitis C Virus (HCV) Monitor, Version 2.0, International Unit Assay and the National Genetics Institute HCV Superquant Assay

The COBAS Amplicor Hepatitis C Virus (HCV) Monitor assay, version 2.0, which reports in international units per milliliter, was compared to the assay reported in copies per milliliter by analyzing dilution series and clinical plasma samples by both methods. In addition, the Amplicor international unit assay was compared to the National Genetics Institute HCV Superquant assay. The dilution series ranged from <100 to 5,000,000 HCV RNA copies/ml and consisted of 32 points, assayed in triplicate in each assay. Thirty clinical samples ranging from 1,000 to 1,000,000 HCV RNA copies/ml were assayed in duplicate. Deming regression analysis comparing the Amplicor HCV RNA international units-per-milliliter and copies-per-milliliter assays was calculated as follows: (Amplicor international units per milliliter) = 1.030(Amplicor copies per milliliter) − 0.392; R(2) = 0.981; n = 28; S(y/x) (standard error of the estimate) = 0.129. The linearity of the Amplicor international units-per-milliliter assay was as follows: observed = 0.886(expected) + 0.437; R(2) = 0.983; n = 30. The linearity of the Superquant assay was as follows: observed= 0.918 (expected) + 0.436; R(2) = 0.986; n = 32. Deming regression analysis comparing the Amplicor and Superquant assays was calculated as follows: Superquant = 1.066(Amplicor) − 0.0197; R(2) = 0.908; S(y/x) = 0.308; n = 28. The Amplicor and Superquant assays were linear through the range of 600 to 600,000 IU of HCV RNA/ml and ∼300 to 5,000,000 HCV RNA copies/ml, respectively. The narrow range of the Amplicor assay means that some samples will require dilution and retesting for accurate quantification above 600,000 IU of HCV RNA/ml. The Amplicor and Superquant assays agreed well within the range of 600 to 600,000 IU of HCV RNA/ml (∼1,000 to ∼1,000,000 HCV RNA copies/ml). Overall, the Amplicor and Superquant assays agree well, and results obtained in one assay could be expected to compare well with results from the other when reported in copies per milliliter