Abbott RealTime Hepatitis C Virus (HCV) and Roche Cobas AmpliPrep/Cobas TaqMan HCV Assays for Prediction of Sustained Virological Response to Pegylated Interferon and Ribavirin in Chronic Hepatitis C Patients

Two commercial real-time PCR assays are currently available for sensitive hepatitis C virus (HCV) RNA quantification: the Abbott RealTime HCV assay (ART) and Roche Cobas AmpliPrep/Cobas TaqMan HCV assay (CAP/CTM). We assessed whether the two real-time PCR assays were more effective than Roche Cobas Amplicor HCV Monitor test, v. 2.0 (CAM) for prediction of the sustained virological response (SVR) to pegylated interferon (PEG-IFN) plus ribavirin (RBV) in chronic hepatitis C. Sixty patients chronically infected with HCV genotype 1b (37 males and 23 females, 53 +/- 12 years of age) were treated with PEG-IFN alpha 2b plus RBV for 48 weeks. Stored specimens at nine time points for each patient (at baseline, on treatment, and 24 weeks after treatment) were tested by the two real-time PCR assays and CAM. Twenty-six (43.3%) patients reached SVR. The positive predictive values (PPVs) for SVR of undetectable HCV RNA at week 12 by CAM, ART, and CAP/CTM were 74.3%, 88.0%, and 95.2%, respectively. An undetectable HCV RNA level by CAM, ART, and CAP/CTM correctly predicted SVR at week 4 in 100%, 100%, and 100% of patients, at weeks 5 to 8 in 91.7%, 100%, and 100% of patients, at weeks 9 to 12 in 55.6%, 75%, and 87.5% of patients, and at weeks 13 to 24 in 0%, 26.7%, and 40% of patients, respectively. Of 16 patients who relapsed after treatment, HCV RNA was detectable in 2 patients at the end of treatment by CAP/CTM but undetectable by ART and CAM. HCV RNA tests using ART and CAP/CTM are considered to be more effective at predicting SVR than CAM, and the PPV for SVR was slightly higher in CAP/CTM than in ART.