1215 Multivariate Models Predict Outcome to Hepatitis C Virus Therapy at Baseline and at Weeks 4 and 8

The benefit of individualizing treatment for patients with genotype 3 HCV infection on the basis of viral clearance at week 4 (wk4-R) has not been firmly established.Four hundred and fourteen patients received Peg-interferon alpha-2b plus 1000–1200 mg of ribavirin daily according with body weight > or <75 kg. Patients were randomized to standard 24 weeks (Std24) or to a 12 or 36 weeks variable treatment duration (Var12/36). In the variable treatment arm, patients with or without wk4-R were allocated to either 12 or 36 weeks duration.At treatment week 4, HCV RNA was undetectable in 262 patients (63.3%), 136 in the Std24, and 126 in the Var12/36 group (p = 0.41). In patients with wk4-R, end-of-treatment (EOT) responses were 80.4% (CI 85.4–95.3) and 97.6% (CI 94.9–99.9) in the two arms, respectively (p = 0.019). In patients without wk4-R, corresponding rates were 61.9% (50.6–73.2) and 75.3% (CI 65.9–84.6) (p = 0.08). SVR was attained in 302 patients, 71.4% (CI 65.3–77.6) in the St24 group and 74.3% (CI 58.4–80.3) in the variable 12/36 arm. Among patients with wk4-R, SVR was 81.6% (CI 75.1–88.1) and 82.5% (75.9–89.1), respectively. In patients without wk4-R, SVR amounted to 52.1% (CI 40.4–63.7) and 61.7 (CI 51.1–72.3) in the two arms (p = 0.25).HCV genotype 3 patients with week4-R may be treated safely with 12 weeks of therapy, provided that sufficiently high doses of ribavirin are administered. For patients still viremic at treatment week 4, SVR rates were numerically higher after 36 weeks of treatment than after the currently recommended 24 weeks.