An a priori prediction model of response to peginterferon plus ribavirin dual therapy in naïve patients with genotype 1 chronic hepatitis C

Background: Aim was to select naïve patients with genotype 1 chronic hepatitis C having a high probability of response to Peg-interferon. +. ribavirin therapy. Methods: In 1073 patients (derivation cohort), predictors of rapid and sustained virological response were identified by logistic analysis; regression coefficients were used to generate prediction models for sustained virological response. Probabilities at baseline and treatment week 4 were utilized to develop a decision rule to select patients with high likelihood of response. The model was then validated in 423 patients (validation cohort). Results: In the derivation cohort, 257 achieved rapid virological response and 818 did not, with sustained virological response rates of 80.2% and 25.4%, respectively; interleukin-28B polymorphisms, fibrosis staging, gamma-glutamyl transferase, and viral load predicted sustained virological response. Assuming a <30% sustained virological response probability for not recommending Peg-interferon. +. ribavirin, 100 patients (25.6%) in the validation cohort were predicted a priori to fail this regimen. Assuming a ≥80% sustained virological response probability as a threshold to continue with Peg-interferon. +. ribavirin, 61 patients were predicted to obtain sustained virological response, and 55 of them (90.2%) eventually did. Conclusions: This model uses easily determined variables for a personalized estimate of the probability of sustained virological response with Peg-interferon. +. ribavirin, allowing to identify patients who may benefit from conventional therapy.