Optimal Erythrocyte Ribavirin Level to Reduce the Risk of Anemia and Obtain an Early Virological Response in Patients with Chronic Hepatitis C Caused by Genotype 1b Infection

Aims. To determine whether the erythrocyte phosphorylated ribavirin (RBV) level might be a useful index of EVR and risk of anemia and to determine the optimal dose of RBV in 24 patients with hepatitis C with pegylated interferon and RBV. Methodology. The RBV level was measured by a high-performance liquid chromatography. Results and Conclusion. In patients aged 50 years or over, a negative correlation (r = −0.548, P < .05) was observed between the RBV level at week 2 and rate of Hb reduction (ΔHb) at week 4. The ΔHb at week 4 was significantly greater in patients with RBV levels of ≥800 μM (−25.5 ± 10.1%) than in patients with RBV levels <800 μM (−15.6 ± 7.7%). None of the patients with RBV levels <600 μM at week 2 achieved EVR and SVR. Thus the optimal levels of erythrocyte phosphorylated RBV at week 2 of therapy in order to achieve EVR without anemia seemed to be 600–800 μM.