REALTIME HCV VIRAL LOAD

For In Vitro Diagnostic Use

For HCV management, especially given the high cost of therapies, excellent performance at clinical decision points is critical for providing reliable results (at 25 IU/ML) to assess SVR. The Abbott RealTime HCV assay delivers accurate quantification of GT 1-6. 

For Information Only - Not a Controlled Copy

 

Leading Science

The Abbott RealTime HCV assay delivers accurate quantification of genotypes 1, 2, 3, 4, 5 and 6, and consists of three reagent kits:

  • Abbott RealTime HCV Amplification Reagent Kit
  • Abbott RealTime HCV Control Kit 
  • Abbott RealTime HCV Calibrator Kit 

Precisely Quantitates HCV Levels At Clinical Decision Points1

The Abbott RealTime HCV assay demonstrated greater precision than other HCV assays at clinical decision points (6 HCV genotype 1 samples, 10 aliquots measured in 10 independent runs, respectively).2

Reliably Assesses Viral Load

The Abbott RealTime HCV assay is highly precise in reliably assessing viral load.

 ASSAYCV (25 IU/ML)*
RealTime (Abbott)27%
CTM v2 (Roche)53%
Versant (Siemens)49%

Detection and Quantitation of HCV Genotypes


Genotype dilution linearity was demonstrated by diluting six specimens, one of each genotype 1 through 6, to target concentrations of 5.0 log IU/ml, 3.5 log IU/ml,  2.0 log IU/ml, and 1.0 log IU/ml. Four replicates were tested at each concentration of each genotype.  The correlation coefficients ranged from 0.994 to 0.998.

 

Correlation to Comparator Assay


Specimens from 131 HCV infected patients were tested with the Abbott RealTime HCV assay and a comparator assay per NCCLS Document EP9-A2. 
 

HCV Viral Load Treatment Monitoring During Therapy3

Excellent analytical performance at clinical decision points (25 IU/ML) is important in providing reliable results in assessing SVR at these specific time points:

HCV Viral Load Treatment Monitoring Time Points


EOT = end of treatment (week 12, 24, or 48). For IFN-free therapy regimens, week 2 testing is for patient adherence. VL = Viral Load, GT = Genotype, SVR = Sustained Virologic Response. For IFN-free therapy regimens, week 2 testing is for patient adherence, week 12 is assumed end of treatment (ED).EASL Clinical Practice Guidelines,Journal of Hepatology 2014 vol. 60 j 392-420. EASL HVC Treatment Recommendations, April 2014. Available at http://www.easl.eu/_newsroom/latest-news/easl-recommendations-on-treatment-of-hepatitis-c-2014. Accessed January 9, 2015. AASLD/IDSA/IAS-USA. Recommendations for testing, managing, and treating hepatitis C. http://www.hcvguidelines.org. Accessed on January 29, 2014. AASLD/IDSA HCV Guidance Panel (2015), Hepatitis C guidance: AASLD-IDSA recommendations for testing, managing, and treating adults infected with hepatitis C virus. Hepatology, 62: 932–954. doi:10.1002/hep.27950
 

Indications and Limitations of Use

Intended Use

The Abbott RealTime HCV assay is an in vitro reverse transcription-polymerase chain reaction (RT-PCR) assay for use with the Abbott mSample Preparation System reagents and with the Abbott m2000sp and m2000rt instruments for the quantitation of hepatitis C viral (HCV) RNA in human serum or plasma (EDTA) from HCV-infected individuals. Specimens containing HCV genotypes 1 – 6 have been validated for quantitation in the assay.

The Abbott RealTime HCV assay is intended for use as an aid in the management of HCV-infected patients undergoing antiviral therapy. The assay measures HCV RNA levels at baseline and during treatment and can be utilized to predict sustained and non-sustained virological response to HCV therapy. The results from the RealTime HCV assay must be interpreted within the context of all relevant clinical and laboratory findings.

Assay performance characteristics have been established for individuals treated with peginterferon alfa-2a or 2b plus ribavirin. No information is available on the assay’s predictive value when other therapies are used. Assay performance for determining the state of HCV infection has not been established.

The Abbott RealTime HCV assay is not for screening blood, plasma, serum or tissue donors for HCV, or to be used as a diagnostic test to confirm the presence of HCV infection.

Limitations of the Procedure

  • Human serum and plasma specimens (EDTA) may be used with the Abbott RealTime HCV assay. The use of other anticoagulants has not been validated with the Abbott RealTime HCV assay.
  • Though rare, mutations within the highly conserved regions of the viral genome covered by the Abbott RealTime HCV assay primers and/or probe may result in the under-quantitation of or a failure to detect the presence of the virus in this circumstance.
  • A specimen with a result of “Not Detected” cannot be presumed to be negative for HCV RNA.
  • Precision was established with HCV Genotypes 1 and 3 only.
  • As with any diagnostic test, results from the Abbott RealTime HCV assay should be interpreted in conjunction with other clinical and laboratory findings.
  • Due to inherent differences between technologies, it is recommended that, prior to switching from one technology to the next, users perform method correlation studies in their laboratory to quantify technology differences.

Warnings and Precautions

The Abbott RealTime HCV assay is not for screening blood, plasma, serum or tissue donors for HCV, or to be used as a diagnostic test to confirm the presence of HCV infection. 

Caution: United States Federal law restricts this device to sale and distribution to or on the order of a physician or to a clinical laboratory; and use is restricted to, by, or on the order of a physician.

References

  1. Wiesmann F et al. Variation analysis of six HCV viral load assays using low viremic HCV samples in the range of the clinical decision points for HCV protease inhibitors. Med Microbiol Immunol. 2015 Aug;204(4):515-25. DOI 10.1007/s00430-014-0364-z. Epub 2014 Nov 15.
  2. Adapted from Wiesmann F et al. Poster #465. ESCV 2013. Comparison of viral load assays for the quantification of HCV genotypes 1-4 in the setting of low viremic samples.
  3. European Association for the Study of the Liver. EASL Clinical Practice Guidelines: Management of hepatitis C virus infection. J Hepatol. 2014; 60(2):392-420.

An Assay Designed with Leading Science

The unique combination of Abbott RealTime HCV assay design features ensures reliable detection of all major HCV genotypes with a high degree of precision.

Conserved Target Region

The target sequence for the Abbott RealTime HCV assay is in the 5´UTR region of the HCV genome. This region is specific for HCV and is highly conserved. The primers are designed to hybridize to the 5´UTR region with the fewest possible mismatches among HCV genotypes 1-6.

 
Unique Probe Design

In the absence of target, the probe achieves quenching through random coiling.

In presence of target, the probe prefers to hybridize to the target sequence, allowing fluorescent detection; cleavage is not required.
 

Optimal Cycling Conditions

The cycling conditions for RealTime HCV encompass a low temperature read cycle. This read cycle allows the probe to tolerate mismatches more effectively than a probe required to bind during the extension phase.

ABBOTT REALTIME HCV PERFORMANCE*
Limit of Detection (LOD)12 IU/mL
Limit of Quantitation (LOQ)12 IU/mL 
Linear Range12 IU/mL (1.08 log IU/mL) to 100 million IU/mL (8.0 log IU/mL)
Target Region5' utr
Genotype DetectionAccurate quantification of genotypes 1, 2, 3, 4, 5 and 6
Internal ControlAdded to lysis buffer during extraction and detected with all samples
CalibrationExternal two point
Specimen TypeHuman serum and plasma (EDTA)
Input Volume0.5mL
PrecisionSD: less than or equal 0.25 log IU/mL
StandardizationSecond World Health Organization international standard to HCV RNA (NIBSC 96/798)

ORDERING INFO