Quantitative viremia test for early prediction of a biochemical response in patients with chronic hepatitis C treated with interferon.

ABSTRACT

To evaluate the importance of the changes in viremia as an early predictor of the outcome of interferon (IFN) therapy, we assayed the levels of hepatitis C virus (HCV)-RNA in stored serum samples obtained from 34 patients with chronic hepatitis C who showed different biochemical responses to therapy. Serum samples obtained before the start of therapy and after 1 and 3 months were used, and viremia levels were determined by "branched DNA (bDNA)" technique. Viremia levels at 1 month of therapy were lower than pre-therapy levels in all 19 patients who had shown a persistent normalization of ALT during therapy (responder patients). The bDNA test was negative, i.e. the levels of viremia were below the sensitivity threshold of the method, in 12 (63.1%) patients at 1 month and in 13 (68.4%) at the 3rd month of therapy, whereas the bDNA test was negative in none of the 15 non-responder patients at the 1st month and in only 2 (13.3%) of them at the 3rd month of therapy. The bDNA test was superior to the ALT test both in predicting the non-response and the biochemical response to IFN after 1 month of therapy. The bDNA test results, instead, were not predictive of the duration of the response to IFN, either at the 1st or 3rd months of therapy. These results seem to indicate the usefulness of measuring the HCV-RNA levels at the beginning and after 1 month of IFN therapy in order to envisage or exclude a possible biochemical response early on in treatment.