Background and study aim : Because of pegylated interferon (Peg-IFN)/ribavirin therapy is poorly tolerated and rates of response are lower in hepatitis C virus (HCV) infected patients of genotype 4, the recognition of predictors of response is a high priority in this population. We aimed to use a baseline noninvasive index to predict early virological response (EVR) to Peg-IFN/ribavirin in HCV-infected individuals, the score included 4 variables: 2 host-related variables (IL28B SNP rs12979860 and liver stiffness) and 2 HCV-related variables (genotype and viral load). Patients and Methods: 96 treatment-naive HCV-infected patients receiving Peg-IFN/ribavirin were analysed and predictive model was used. The areas under the receiver operating characteristic (AUROC) curves (95% CI), sensitivity and specificity, as well as negative and positive predictive values, were calculated. Only individuals who had completed a course of Peg-IFN-RBV therapy were considered. Results: EVR was achieved in (60.4 %) of patients. The area under the receiver operating characteristic curve (AUROC) was 0.849 (0.762-0.914). Using three cut-off values, maximum specificity and sensitivity were 81.5% and 77.5%, respectively, with a negative predictive value for EVR of 80% and a positive predictive value of 83.6%. Seventeen individuals were misclassified using optimal cut-off values. Conclusion: The probability of achieving EVR with Peg-IFN-RBV therapy in HCV-infected patients can be reliably estimated prior to initiation of therapy using Prometheus index that includes 4 noninvasive parameters. Prometheus index represents a reliable and easily applicable tool to individually evaluate the probability of achieving an EVR to Peg-IFN/ribavirin among HCV-infected patients.