Abbott RealTime HBV assay is more sensitive in detection of low viral load and little impacted by drug resistant mutation in chronic hepatitis B patients under nucleot(s)ide analogues therapy

Performance Evaluation of the Roche Cobas 5800 HBV and HCV Tests: Comparison of the 200 and 500 μL Protocols

Background

Clinical management of patients infected with hepatitis B virus (HBV) or hepatitis C virus (HCV) relies on the viral load (VL). The Cobas 5800 system (Roche Diagnostics) can determine VLs in 200 and 500 μL samples, but the performance of each protocol has not been compared. We evaluated the performance of both protocols for the HBV and HCV tests.

Methods

Precision and linearity were verified using commercial panels. Probit analyses were used to determine limits of detection (LoDs). The results obtained with 336 samples were compared using the 200 and 500 μL protocols. Data from 6,737 retrospective HBV and 768 HCV samples were compared to estimate the effects of the different LoDs on the diagnostic results of the protocols. Correlations between protocols were tested with Spearman's rank correlation coefficients (rho).

Results

The precision and linearity of both protocols were verified. The LoDs for the 200 and 500 μL protocols were 6.5 and 2.7 IU/mL for HBV and 29.7 and 8.2 IU/mL for HCV, respectively. The agreement between the protocols ranged from 0.8 to 1.0. The results obtained with the HBV and HCV tests showed a strong correlation (rho=0.994). Only 0.4% of HBV and 0.4% of HCV test results were affected by the LoDs of the 200 μL protocol.

Conclusions

The Cobas 5800 200 and 500 μL protocols for the HBV DNA and HCV RNA tests demonstrated excellent performance. These findings establish the 200 μL protocol as a new option for low-volume samples, especially for pediatric and difficult-to-bleed patients.

Comparison of the Amplisure HBV Quantitative Kit with the Qiagen Artus HBV QS-RGQ Assay for Quantifying Viral DNA in Plasma Samples of Monitoring Cases

BACKGROUND

Monitoring of hepatitis B virus (HBV) viral load has become an essential phase in the treatment of HBV. There are many commercial assays available for HBV viral load quantification. In this study, we have evaluated the performance characteristics of Amplisure® HBV Kit in comparison with the Qiagen artus HBV QS-RGQ kit for HBV DNA quantitation.

METHODS

Comparison of 2 methods was carried out on 200 clinical samples, 150 HBV DNA positive and 50 HBV DNA negative, by a reference method. Results obtained with Amplisure® HBV Kit (Amplisure HBV) were compared using the Qiagen artus HBV QS-RGQ assay results as the comparator method.

RESULT

The overall performance of the Amplisure HBV compared with the comparator method shows positive and negative clinical agreement of 100 and 76%, respectively. Among the 12 qualitative discrepant samples, all positive with Amplisure HBV were sequenced and 10 were below comparator method's LOD. For 5 weak positives (-0.22 to 0.98 log IU/mL), the sequencing failed. The 7 other positives (0.48 to 1.89 log IU/mL) were confirmed positive by sequencing. Quantitative comparison gave an r2 of 0.967 with a mean log difference of 0.09 log10 IU/mL.

CONCLUSION

This study shows that Amplisure® HBV Quantitative Kit shows comparable performance with artus HBV QS-RGQ assays and can be useful in management and therapeutic monitoring of HBV in a clinical practice.

Comparison of Amplix® hepatitis B virus and Roche COBAS AmpliPrep/COBAS Taqman hepatitis B virus assay in quantifying HBV DNA in plasma of chronic hepatitis B in Senegal

Introduction

quantification of hepatitis B virus DNA, a key element in the management of chronic hepatitis B, allows a more direct and reliable measurement of viral replication and monitoring of the virological response to therapy. Polymerase chain reaction (PCR) platforms performing this quantification and adaptable to intermediate laboratories have been developed. Thus, this study was conducted to evaluate the on-site performance of the AMPLIX® hepatitis B virus (HBV) real-time PCR technique in comparison with the COBAS AmpliPrep™ technique.

Methods

performance of the AMPLIX® HBV real-time PCR technique was evaluated with repeatability and intermediate precision (reproducibility) determined. The comparison with COBAS Taqman was performed by testing, in parallel, 42 plasma samples. The statistical analysis using Meth Val® software was focused on correlation and concordance determination.

Results

AMPLIX® real-time PCR assay showed good reproducibility for the low (CV=6.65%) and high (CV=3.15%) control levels but also good repeatability for both the low (CV=2.12%) and high (CV=1.60%) concentration levels. Accuracy obtained in our study were less than acceptability limit fixed to 5%. Viral load measurements between Amplix and COBAS Taqman correlated strongly with a correlation coefficient of 0.97%. Concordance analysis gave an average of the differences of 0.54 log IU/L between the viral load measurements of the 2 techniques.

Conclusion

based on these results, the Amplix real-time PCR platform for the quantification of HBV DNA can be considered as a reliable system for the monitoring of chronic hepatitis B and also a system adapted to intermediate laboratories.

Performance of the cobas Hepatitis B virus (HBV) test using the cobas 4800 system and comparison of HBV DNA quantification ability between the COBAS AmpliPrep/COBAS TaqMan HBV test version 2.0 and cobas HBV test

BACKGROUND

Hepatitis B virus (HBV) DNA levels are used to predict the response to therapy, determine therapy initiation, monitor resistance to therapy, and establish treatment success.

OBJECTIVE

To verify the performance of the cobas HBV test using the cobas 4800 system for HBV DNA quantification and to compare the HBV DNA quantification ability between the cobas HBV test and COBAS AmpliPrep/COBAS TaqMan HBV version 2.0 (CAP/CTM v2.0).

STUDY DESIGN

The precision, linearity, and limit of detection of the cobas HBV test were evaluated using the 4th World Health Organization International Standard material and plasma samples. Clinical samples that yielded quantitative results using the CAP/CTM v2.0 and cobas HBV tests were subjected to correlational analysis.

RESULTS

Three hundred forty-nine samples were subjected to correlational analysis, among which 114 samples showed results above the lower limit of quantification. Comparable results were obtained ([cobas HBV test] = 1.038 × [CAP/CTM v2.0]-0.173, r = 0.914) in 114 samples, which yielded values above the lower limit of quantification. The results for 86.8% of the samples obtained using the cobas HBV test were within 0.5 log₁₀ IU/mL of the CAP/CTM v2.0 results. The total precision values against the low and high positive controls were 1.4% (mean level: 2.25 log₁₀ IU/mL) and 3.2% (mean level: 6.23 log₁₀ IU/mL), respectively. The cobas HBV test demonstrated linearity (1.15-6.75 log₁₀ IU/mL, y = 0.95 × 6 + 0.17, r² = 0.994).

CONCLUSION

The cobas HBV test showed good correlation with CAP/CTM v2.0, and had good precision and an acceptable limit of detection. The cobas HBV test using the cobas 4800 is a reliable method for quantifying HBV DNA levels in the clinical setting.

A European multicenter study on the analytical performance of the VERIS HBV assay

BACKGROUND

Hepatitis B viral load monitoring is an essential part of managing patients with chronic Hepatits B infection. Beckman Coulter has developed the VERIS HBV Assay for use on the fully automated Beckman Coulter DxN VERIS Molecular Diagnostics System.¹ OBJECTIVES: To evaluate the analytical performance of the VERIS HBV Assay at multiple European virology laboratories.

STUDY DESIGN

Precision, analytical sensitivity, negative sample performance, linearity and performance with major HBV genotypes/subtypes for the VERIS HBV Assay was evaluated.

RESULTS

Precision showed an SD of 0.15 log₁₀ IU/mL or less for each level tested. Analytical sensitivity determined by probit analysis was between 6.8-8.0 IU/mL. Clinical specificity on 90 unique patient samples was 100.0%. Performance with 754 negative samples demonstrated 100.0% not detected results, and a carryover study showed no cross contamination. Linearity using clinical samples was shown from 1.23-8.23 log₁₀ IU/mL and the assay detected and showed linearity with major HBV genotypes/subtypes.

CONCLUSIONS

The VERIS HBV Assay demonstrated comparable analytical performance to other currently marketed assays for HBV DNA monitoring.

A European multicientre study on the comparison of HBV viral loads between VERIS HBV assay and Roche COBAS® TAQMAN® HBV test, Abbott RealTime HBV assay, Siemens VERSANT HBV assay, and Qiagen artus HBV RG kit

BACKGROUND

Hepatitis B viral load testing is essential to treatment and monitoring decisions in patients with chronic Hepatitis B. Beckman Coulter has developed the VERIS HBV Assay (Veris) for use on the fully automated DxN VERIS Molecular Diagnostics System.¹ OBJECTIVES: To evaluate the clinical performance of the Veris HBV Assay at multiple EU laboratories STUDY DESIGN: Method comparison was performed with a total of 344 plasma specimens from HBV infected patients tested with Veris and COBAS^® TaqMan^® HBV Test (Cobas), 207 specimens tested with Veris and RealTime HBV Assay (RealTime), 86 specimens tested with Veris and VERSANT^® HBV Assay (Versant), and 74 specimens tested with Veris and artus^® HBV RG PCR kit (artus).

RESULTS

Bland-Altman analysis showed average bias of -0.46 log₁₀ IU/mL between Veris and Cobas, -0.46 log₁₀IU/mL between Veris and RealTime, -0.36 log₁₀IU/mL between Veris and Versant, and -0.12 log₁₀IU/mL between Veris and artus. Bias was consistent across the assay range. Patient monitoring results using Veris demonstrated similar viral load trends over time to Cobas, RealTime, and artus.

CONCLUSIONS

The VERIS HBV Assay demonstrated comparable clinical performance, with varying degrees of negative bias, compared to other currently marketed assays for HBV DNA monitoring. This negative bias should be taken into consideration if switching monitoring methods to Veris.

Boceprevir-based triple therapy to rescue HCV genotype 1/HBV dually infected patients refractory to peginterferon plus ribavirin combination therapy in Taiwan

BACKGROUND/PURPOSE

The role of directly-acting antivirals (DAA)-containing regimens in the treatment of patients dually-infected with hepatitis C virus (HCV) and hepatitis B virus (HBV) remains unclear. The pilot study aimed to explore the safety and efficacy of a protease inhibitor, boceprevir, in combination with peginterferon/ribavirin for HCV genotype 1 (HCV-1)/HBV dually-infected patients refractory to prior peginterferon/ribavirin.

METHODS

Twelve peginterferon-experienced patients dually-infected with HCV-1/HBV were assigned to receive boceprevir 800 mg, twice a day, plus peginterferon-α 2b 1.5 μg/kg/week and ribavirin 800-1400 mg/day for 36 or 48 weeks. The primary endpoint was HCV sustained virological response (SVR, HCV RNA undetectable 24 weeks after end-of-treatment).

RESULTS

Five patients terminated treatment early due to adverse events (one at week 4, one at week 46), virological failures (one non-response and one breakthrough), and patient request (n = 1). Eight patients achieved HCV SVR (66.7% in full-analysis set and 72.7% in modified intention-to-treat population). The HCV SVR rate was 71.4% (5/7) in prior relapsers, 60.0% (3/5) in prior null responder; 75% in non-cirrhotic and 50% in cirrhotic patients. All four patients of prior non-cirrhotic relapsers received 36-week regimen and achieved HCV SVR. There was no HBV-related hepatic flare. All patients experienced at least one adverse event. Two had serious adverse events.

CONCLUSION

Boceprevir plus peginterferon/ribavirin is effective in the treatment of HCV-1/HBV dually infected patients' refractory to prior peginterferon/ribavirin combination therapy.

Comparison of the QIAGEN artus HBV QS-RGQ Assay With the Roche COBAS AmpliPrep/COBAS TaqMan HBV Assay for Quantifying Viral DNA in Sera of Chronic Hepatitis B Patients

BACKGROUND

Hepatitis B virus DNA quantification is essential for managing chronic hepatitis B (CHB). We compared the performance of artus HBV QS-RGQ (QIAGEN GmbH, Germany) and CAP/CTM v2.0 HBV assays (Roche Molecular Diagnostics, USA) in CHB patients.

METHODS

A comparative evaluation between two assays was performed with 508 clinical serum samples. Precision, linearity, and the limit of detection (LOD) of QS-RGQ assay was evaluated by using the WHO standard 97/750 and clinical samples.

RESULTS

Detection rates and viral loads as determined QS-RGQ assay were significantly lower than those from the CAP/CTM v2.0 assay (52.8% vs 60.6%; 3.55±1.77 IU/mL vs 4.18±1.89 IU/mL, P<0.0001). The kappa coefficient between qualitative results was 0.79 (95% confidence interval, 0.74 to 0.85). Bland-Altman plot found a mean difference of (QS-RGQ - CAP/CTM v2.0)=-0.63 log₁₀ IU/mL (95% limit of agreement, -1.48 to 0.22). Repeatability and total imprecision (% CV) of the QS-RGQ assay were 1.0% and 1.1% at 2,000 IU/mL, and 0.7% and 1.4% at 20,000 IU/mL, respectively. Linearity of this assay ranged from 31.6 to 1.0±10⁷ IU/mL, and the LOD was 2.95 IU/mL.

CONCLUSIONS

The artus HBV QS-RGQ assay showed good performance but significantly decreased detection rate and viral load compared with CAP/CTM v2.0 assays. This assay recommends using plasma; however, we used stored serum because of the retrospective study design. Usually HBV DNA quantification is performed in plasma or serum, but sample type and clinical relevance of quantitative values should be considered when determining the clinical application of this reagent.

Review of Laboratory Tests used in Monitoring Hepatitis B Response to Pegylated Interferon and Nucleos(t)ide Analog Therapy

There are only two currently approved classes of hepatitis B virus (HBV) antiviral agents, pegylated interferon (Peg-IFN), and nucleos(t)ide analogs (NAs) for chronic HBV infection. Although Peg-IFN is used for a finite 48-week duration and offers a greater chance of sustained off-treatment virological response, it is poorly tolerated and can only be offered to selected patients. The NAs are well tolerated but require prolonged therapy due to risk of relapse with treatment cessation. There is evolving data that novel virological assays (e.g., quantitative hepatitis B surface antigen, quantitative hepatitis B core antigen, quantitative antibody to core protein) in combination with hepatitis B genotype and more sensitive HBV DNA polymerase chain reaction (PCR) assays may be useful to predict response to IFN as well as off-treatment NA durability. Utilization of these clinical laboratory tests may be important given the development of novel anti-HBV therapies, hoping to achieve a cure for chronic hepatitis B infection.