The investigators hypothesized and have now demonstrated that CXCL10 is being cleaved in situ, resulting in the generation of an antagonist form of the chemokine. Based on the use of specific inhibitors, the investigators now propose to test whether protection of the agonist form of CXCL10 will increase responsiveness to peg-IFN-alfa2 / ribavirin therapy. This can be achieved using DPPIV inhibitors, targeting the enzyme responsible for N-terminal truncation of CXCL10. If safety is confirmed, the efficacy of DPPIV-inhibition in HCV patients will be tested in future trials that examine potential clearance benefits.