High sustained virologic response rates in rapid virologic response patients in the large real-world PROPHESYS cohort confirm results from randomized clinical trials

UNLABELLED: The ability to predict which patients are most likely to achieve a sustained virologic response (SVR) with peginterferon/ribavirin would be useful in optimizing treatment for hepatitis C virus (HCV). The objective of this large international noninterventional cohort study was to investigate the predictive value (PV) of a virologic response (VR) by weeks 2, 4, and 12 of treatment on SVR. Treatment-naive HCV monoinfected patients (N = 7,163) age ≥ 18 years were prescribed peginterferon/ribavirin at the discretion of the treating physician according to country-specific requirements in accordance with the local label. The main outcome measure was the PV of a VR (HCV RNA <50 IU/mL) by weeks 2, 4, and 12 of treatment for SVR24 (HCV RNA <50 IU/mL after 24 weeks of untreated follow-up) by HCV genotype. The overall SVR24 rate was 49.4% (3,541/7,163; 95% confidence interval [CI]: 48.3-50.6%). SVR24 rates in patients with an HCV RNA titer <50 IU/mL by weeks 2, 4, and 12, respectively, were 66.2% (95% CI: 60.4-71.7%), 68.4% (95% CI: 65.7-71.0%), and 60.3% (95% CI: 58.5-62.1%) among genotype 1 patients; 82.0% (95% CI: 76.8-86.5%), 76.3% (95% CI: 73.3-79.1%), and 74.2% (95% CI: 71.3-76.9%) among genotype 2 patients; 67.3% (95% CI: 61.1-73.1%), 67.3% (95% CI: 64.2-70.3%), and 63.8% (95% CI: 61.0-66.6%) among genotype 3 patients; and 59.4% (95% CI: 40.6-76.3%), 63.3% (95% CI: 54.3-71.6%), and 54.3% (95% CI: 47.5-60.9%) among genotype 4 patients. The absence of a VR by week 12 had the highest negative PV across all genotypes. CONCLUSION: A VR by week 2 or 4 had the highest positive PV for SVR24 and differed according to HCV genotype.