The role of pro-fibrogenic cytokines in the outcome of infections with hepatitis C virus (HCV) and the response to treatment with pegylated interferon-alpha (pegIFNalpha) and ribavirin remains unclear. To address this issue, we assessed hepatic fibrosis and plasma markers pertinent to T-cell mediated fibrogenesis and inflammation at the start of treatment. Levels of soluble (s)CD30, interleukin-13 receptor alpha 2 (IL-13Ralpha2), total and active transforming growth factor-beta 1 (TGFbeta1), interleukin-18 (IL-18) and interferon-gamma inducible protein-10 (IP-10, CXCL10) were correlated with the severity of fibrosis and with treatment outcome using multiple logistic regression modelling. The Hepascore algorithm was confirmed as a marker of fibrosis, but was a poor predictor of treatment outcome. Inclusion of all immunological markers improved prediction based on Hepascore alone (p=0.045), but optimal prediction was achieved with an algorithm ("TIPscore") based on TGFbeta1 (total), IP-10, age, sex and HCV genotype (p=0.003 relative to Hepascore). Whilst this was only marginally more effective than predictions based on HCV genotype age and sex (p=0.07), it associates high TGFbeta1 and low IP-10 levels with a failure of therapy.