BACKGROUND: The current standard for determining sustained virologic response (SVR) in patients treated for hepatitis C virus (HCV) infection is undetectable serum HCV-RNA 24 weeks after treatment. This study evaluates the value of HCV-RNA determination at 12 weeks posttreatment (W+12) to predict SVR in liver transplant (LT) patients treated with pegylated interferon and ribavirin for recurrent HCV infection. METHODS: This study, performed in 2001 to 2010, included HCV-LT patients with an end-of-treatment response (undetectable serum HCV-RNA) and HCV-RNA testing at 12 and 24 weeks posttreatment (W+12/W+24). HCV-RNA was detected with a qualitative polymerase chain reaction assay (detection limit 50 IU/mL) and, when positive, measured by quantitative PCR (detection limit 600 IU/mL) up to 2006. Since 2007, a real-time PCR-based test (detection limit 15 IU/mL) has been used. The positive predictive value (PPV) was defined as the probability that SVR would occur in patients with undetectable HCV-RNA at W+12 and W+24. RESULTS: Of 162 patients treated during the study period, 57 (35%) had end-of-treatment response and were included. Of these, 45 (79%) had SVR and 12 (21%) had virologic relapse. At W+12, HCV-RNA was undetectable in 45 (79%) patients, all of whom had SVR, yielding a PPV for SVR at W+12 of 100% (95% confidence interval, 75.8%-100%). CONCLUSIONS: Undetectable HCV-RNA at W+12 posttreatment has a high PPV for predicting SVR. HCV-RNA testing to assess SVR at this time point seems as valid as W+24 testing and could be considered for predicting SVR in HCV-LT patients receiving treatment with pegylated interferon and ribavirin.
BACKGROUND: The current standard for determining sustained virologic response (SVR) in patients treated for hepatitis C virus (HCV) infection is undetectable serum HCV-RNA 24 weeks after treatment. This study evaluates the value of HCV-RNA determination at 12 weeks posttreatment (W+12) to predict SVR in liver transplant (LT) patients treated with pegylated interferon and ribavirin for recurrent HCV infection. METHODS: This study, performed in 2001 to 2010, included HCV-LTpatients with an end-of-treatment response (undetectable serum HCV-RNA) and HCV-RNA testing at 12 and 24 weeks posttreatment (W+12/W+24). HCV-RNA was detected with a qualitative polymerase chain reaction assay (detection limit 50 IU/mL) and, when positive, measured by quantitative PCR (detection limit 600 IU/mL) up to 2006. Since 2007, a real-time PCR-based test (detection limit 15 IU/mL) has been used. The positive predictive value (PPV) was defined as the probability that SVR would occur in patients with undetectable HCV-RNA at W+12 and W+24. RESULTS: Of 162 patients treated during the study period, 57 (35%) had end-of-treatment response and were included. Of these, 45 (79%) had SVR and 12 (21%) had virologic relapse. At W+12, HCV-RNA was undetectable in 45 (79%) patients, all of whom had SVR, yielding a PPV for SVR at W+12 of 100% (95% confidence interval, 75.8%-100%). CONCLUSIONS: Undetectable HCV-RNA at W+12 posttreatment has a high PPV for predicting SVR. HCV-RNA testing to assess SVR at this time point seems as valid as W+24 testing and could be considered for predicting SVR in HCV-LTpatients receiving treatment with pegylated interferon and ribavirin.