Viral kinetics in patients with chronic hepatitis C treated with the serine protease inhibitor BILN 2061.

We analysed viral kinetics from a 2-day treatment with BILN 2061, a serine protease inhibitor of hepatitis C virus, in patients chronically infected with genotype 1 hepatitis C virus. The efficiency (E), describing inhibition of viral production, was above 99.45% in all patients with minor or moderate fibrosis receiving doses of 200mg and 500 mg twice daily and larger than in previous studies for interferon-based treatments. However, epsilon was slightly smaller in patients with cirrhosis given 200mg and markedly smaller in patients given 25 mg. Estimates of viral clearance and infected-cell loss support conclusions on these rates and on treatment mechanisms from previous studies on interferon-alpha-based treatments.