Comparison of the VERSANT™ HCV RNA qualitative assay (transcription-mediated amplification) and the COBAS AMPLICOR™ hepatitis C virus test, version 2.0, in patients undergoing interferon- ribavirin therapy Jeffrey J. Germer a , Nizar N. Zein b , Mohamed A. Metwally b , Tanya L. Hoskin c , W. Scott Harmsen c , Thomas F. Smith a , Robin Patel a,d, * a Division of Clinical Microbiology, Mayo Clinic, Rochester, MN, USA b Division of Gastroenterology and Hepatology and Internal Medicine, Mayo Clinic, Rochester, MN, USA c Section of Biostatistics, Mayo Clinic, Rochester, MN, USA d Division of Infectious Diseases, Mayo Clinic, Rochester, MN, USA Abstract Hepatitis C virus (HCV)-infected patients were tested for the presence of HCV RNA using two qualitative assays at various time points during interferon-ribavirin therapy. Among patients treated for 48 weeks, transcription-mediated amplification and the COBAS AMPLICOR Hepatitis C Virus Test results at Week 24 predicted subsequent virologic non-response or virologic relapse in 12/15 (80%) and 8/15 (53%) patients, respectively. © 2003 Elsevier Inc. All rights reserved. The VERSANT HCV RNA Qualitative Assay utilizing transcription-mediated amplification technology (TMA; Bayer HealthCare LLC, Berkeley, CA) can reportedly de- tect HCV RNA at concentrations 10 International Units (IU)/mL with 98% specificity (Sawyer et al., 2000; Ross et al., 2001; Krajden et al., 2002). Currently, the most widely used method of qualitative HCV RNA detection in the United States is the COBAS AMPLICOR Hepatitis C Virus Test, Version 2.0 (AMPLICOR; Roche Molecular Systems, Inc., Branchburg, NJ) utilizing reverse transcrip- tion-polymerase chain reaction (RT-PCR) technology. The AMPLICOR assay has a limit of detection ranging from 60 to 100 IU/mL (for plasma and serum, repectively) combined with a specificity approaching 100% (Lee et al., 2000; Roche Molecular Systems 2001). The performance charac- teristics of both TMA and AMPLICOR are well established, and both have received U.S. Food and Drug Administration (FDA) approval for the qualitative detection of HCV RNA in patient specimens. Recent anti-HCV treatment algorithms suggest that tai- loring antiviral therapy based on HCV genotype as well as viral titer can optimize therapeutic outcome in patients chronically infected with HCV (EASL 1999; NIH 2002). Patients chronically infected with HCV genotypes 2 and 3 are more likely to respond to interferon-ribavirin combina- tion therapy than are those infected with HCV genotype 1 (NIH 2002). Furthermore, sustained virologic response, de- fined by the absence of detectable HCV RNA 24 weeks post-treatment, among patients infected with genotypes 1, 2, and 3 has been correlated with a low pre-treatment viral titer (NIH 2002). Clearance of HCV RNA, as determined by RT-PCR, at various time points during interferon-ribavirin combination therapy (including prior to the end-of-treat- ment) has also been suggested as a predictor of sustained virologic response following therapy (Brouwer et al., 1999; McHutchison et al., 1999; McHutchison et al., 2001). It has recently been shown that the increased sensitivity of TMA, as compared to RT-PCR, can improve the detection of extremely low levels of HCV RNA in end-of-treatment specimens and serve as a predictor of sustained virologic response following anti-HCV therapy (Sarrazin et al., 2000; Comanor et al., 2001; Sarrazin et al., 2001). However, there is currently a lack of data concerning the use of the more sensitive TMA with specimens obtained from patients while * Corresponding author. Tel.: +1-507-255-6482; fax: +1-507-255- 7767. E-mail address: patel.robin@mayo.edu (R. Patel). Diagnostic Microbiology and Infectious Disease www.elsevier.com/locate/diagmicrobio 47 (2003) 615– 618 0732-8893/03/$ – see front matter © 2003 Elsevier Inc. All rights reserved. doi:10.1016/S0732-8893(03)00149-4