PERFORMANCE OF VERSION 2.0 OF THE COBAS® AMPLIPREP/COBAS® TAQMAN (CAP/CTM) REAL-TIME POLYMERASE CHAIN REACTION ASSAY FOR HEPATITIS B VIRUS DNA QUANTIFICATION

August 24, 2010

J. Clin. Microbiol. doi:10.1128/JCM.01306-10

Authors/Institutions. .

PERFORMANCE OF VERSION 2.0 OF THE COBAS® AMPLIPREP/COBAS® TAQMAN (CAP/CTM)

REAL-TIME POLYMERASE CHAIN REACTION ASSAY FOR HEPATITIS B VIRUS DNA

QUANTIFICATION

Stéphane Chevaliez*, Magali Bouvier-Alias, Syria Laperche, Christophe Hézode,

and Jean-Michel Pawlotsky

National Reference Center for Viral Hepatitis B, C and delta, Department of

Virology, Hôpital Henri Mondor, Université Paris-Est, Créteil, France; INSERM

U955, Créteil, France; National Reference Center for Viral Hepatitis B, C and

delta in Blood Transfusion, Institut National de la Transfusion Sanguine, Paris,

France; Department of Hepatology and Gastroenterology, Hôpital Henri Mondor,

Université Paris-Est, Créteil, France

* To whom correspondence should be addressed. Email:

stephane.chevaliez@....

Abstract

Hepatitis B virus (HBV) DNA detection and quantification are essential to

diagnose and treat chronic HBV infection. The use of real-time PCR assays for

HBV DNA quantification is strongly recommended. The goal of this study was to

evaluate the intrinsic characteristics and clinical performances of version 2.0

(v2.0) of the COBAS® AmpliPrep/COBAS® TaqMan® (CAP/CTM) assay, a fully automated

platform for HBV DNA quantification in serum or in plasma with a claimed lower

limit of detection of 20 IU/mL and a claimed upper limit of quantification of

1.7 x 108 IU/mL. The specificity of the assay was 99% (95% confidence interval:

94.7-100%). Intra-assay and inter-assay coefficients of variation ranged from

0.21% to 2.67%, and 0.65% to 2.25%, respectively. Calibration of the assay was

found to be satisfactory. Study of blood specimens from patients infected with

HBV genotypes A to F showed a good correspondence between HBV DNA levels

measured with CAP/CTM v2.0, version 1.0 of the same assay and the third

generation " branched DNA " assay. CAP/CTM v2.0 equally quantified HBV DNA levels

in serum or plasma from the same patients. In conclusion, the new version of the

CAP/CTM assay is sensitive, specific and reproducible. It accurately quantifies

HBV DNA levels in patients chronically infected with HBV genotypes A to F.

Improvements made to ensure equal quantification of HBV DNA in serum and plasma

have been successful. Overall, the CAP/CTM assay version 2.0 is well suited to

monitoring clinical HBV DNA levels according to current Clinical Practice

Guidelines.

August 24, 2010