10 RIBAVIRIN CONCENTRATION AT WEEK FOUR IS AN INDEPENDEND PREDICTOR FOR SUSTAINED VIROLOGICAL RESPONSE AFTER TREATMENT OF HEPATITIS C GENOTYPE 2/3 (NORDYNAMIC TRIAL)

Background and Aims:The relatively high rate of relapse after a 12-16 weeks course of treatment is the main concern on shortening treatment duration for HCV genotype 2 and 3 patients.To delineate predictors of relapse after short treatment duration in patients with HCV clearance at treatment week 4 (RVR) and to report sustained virological response (SVR) rates after a second 24 weeks course in RVR patients who experienced a relapse.Methods: After RVR, naive patients were treated with PegIFN alpha 2b (1.5 mg/Kg) and ribavirin (1000-1200 mg) for 12 weeks.Patients who cleared the virus at the end of treatment (EOT) but had a detectable HCVRNA at the end of 24 weeks follow up underwent re-treatment with the same dosages of both PegIFN alfa 2b and ribavirin but for an extended duration of 24 weeks.Logistic regression analysis was applied to delineate baseline features of SVR to short treatment course by using age, gender, route of transmission, BMI, serum ALT, HCV genotypes, serum HCVRNA levels and platelets counts as covariates.Results: Of 790 patients with genotype 2 and 3 who consecutively underwent treatment from January 2005 at our centers, 496 (mean age 51.6 yrs, M/F 3:2) tested HCVRNA negative at treatment week 4 (63%): EOT response rate was observed in 96% of them and SVR in 82%.Of patients with EOT response, 14% relapsed off-therapy.Factors predictive of relapse were age older than 45 yrs (p = 0.004), BMI > 27 kg/m 2 (p = 0.0001), platelets counts <140,000 mm 3 (p = 0.0001).At logistic regression analysis, only platelets counts (p = 0.001, OR 2.5, 95% CI 1.49-4.20)and BMI (p = 0.036, OR1.7, 95% CI 1.03-2.7)were independently associated with SVR.In the subset of patients without these unfavourable predictors, relapse rate was only 7%.Forty three of 67 patients with relapse agreed to be re-treated.SVR was achieved in 47 (70%) of them.Conclusions: Almost all genotype 2 and 3 patients who achieves RVR maybe cured with only 12 weeks of PegIFN alfa 2b and weight based ribavirin.Standard (24 weeks) treatment duration should be reserved only to patients with PLT < 140,000 mm 3 and/or BMI > 27 kg/m 2 .