Introduction: Interferon-g-inducible protein-10 (IP-10)
serum levels are associated with IL28B genotype and may predict response to interferon/ribavirin-based therapy in chronic hepatitis C patients. Our aim was to relate IP-10 levels before and during treatment to treatment outcome, viral HCV-RNA kinetics and IL28B genotype. Patients and methods: A cohort of chronic hepatitis C patients was treated with high-dose interferon for six weeks, followed by standard peginterferon/ ribavirin for 24 or 48 weeks. IP-10 and HCV-RNA levels were frequently determined before, during and after treatment. Results: IP-10 levels increased from log2.56 pg/ml at baseline to log3.48 pg/ml at Day 1 and gradually diminished thereafter. IP-10 levels at any time point were not statistically different between patients with or without sustained viral response (SVR). Patients with IL28B CC genotype had significantly lower baseline IP-10 levels (p = 0.019) and a higher increase of IP-10 levels from baseline to Day 1 than patients with IL28B non-CC genotypes (p = 0.015). Patients with HCV-RNA decline ≥ 2.28log10 at Day 1 had significantly lower baseline IP-10 levels (p = 0.016) and a higher increase of IP-10 levels from baseline to Day1 (p = 0.047) than patients with HCV-RNA decline of < 2.28log10 at Day 1. Conclusions: In patients treated with high induction dose interferon, IP-10 levels at any time point were not predictive for SVR. Low baseline IP-10 levels and a higher increase of IP-10 levels from baseline to Day 1 were associated with IL28B CC genotype and HCV-RNA decline ≥ 2.28log10 at Day 1. This suggests that, in our cohort, for prediction of SVR the added value of IP-10 to IL28B genotype and early viral kinetics is limited.