Detection of low HCV viraemia by repeated HCV RNA testing predicts treatment failure to triple therapy with telaprevir

Aliment Pharmacol Ther. 2013 Nov 10. doi: 10.1111/apt.12544. [Epub ahead of print]

Maasoumy B, Cobb B, Bremer B, Luk K, Halfon P, Aslam S, Manns MP, Cornberg M, Wedemeyer H.

Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany.

Abstract

BACKGROUND: Early on-treatment virological response is one of the most important predictors for sustained virological response (SVR) to treatment of chronic hepatitis C virus (HCV) genotype 1 infection with triple therapy including HCV protease inhibitors (PI). Treatment duration (24 vs. 48 weeks) is based on HCV RNA results at weeks 4 and 12 of PI therapy when HCV RNA must be 'undetectable' to allow shorter therapy.

AIM: To analyse the reliability of HCV RNA measurements at key decision time points (weeks 4 and 12) and the predictive value of concordant or discordant assay results for SVR.

METHODS: Weeks 4 and 12 samples of patients receiving telaprevir-containing triple therapy were initially tested with the AmpliPrep/COBAS-TaqMan_HCV-Test-v1.0 (limit of detection; LOD = 15IU/mL) and retested with the AmpliPrep/COBAS-TaqMan_HCV-Test-v2.0 (LOD = 15IU/mL) and the High_Pure/COBAS-TaqMan_HCV-Test-v2.0 (LOD = 20IU/mL).

RESULTS: Concordance among the three test results in classifying samples as HCV RNA 'undetectable' or 'detectable' was only 55% at week 4, but 85% at week 12. Retesting of 'undetectable' week 4 samples with the respective other assays revealed positive HCV RNA results in 32-50%. In 30%, HCV RNA was 'undetectable' by all three tests at week 4 and all of these patients achieved SVR. In contrast, treatment failure occurred in 62% of patients with at least one 'detectable' result, including cases with one or two other 'undetectable' tests at week 4.

CONCLUSIONS: A single 'undetectable' HCV RNA result at week 4 is not always associated with achieving SVR. Repeated testing in difficult-to-treat patients may identify those at risk for treatment failure.

© 2013 John Wiley & Sons Ltd.

PMID: 24206524 [PubMed - as supplied by publisher]

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