SAN FRANCISCO, CA—Results from a Phase 3b study presented at The Liver Meeting® 2015 suggest that 3D ± ribavirin (RBV) achieved high rates of on-treatment response and was well tolerated with a low rate of discontinuation due to adverse events in hepatitis C virus (HCV) genotype 1 (GT1) infected patients.

Ombitasvir/paritaprevir/ritonavir + dasabuvir (3D) ± ribavirin (RBV) demonstrated in Phase 3 trials high SVR12 rates with a favorable safety profile in HCV GT1 patients, including those with compensated cirrhosis.

TOPAZ-I and TOPAZ-II studies are evaluating the influence of SVR12 on progression of liver disease through 5 years post-treatment in a wide range of patients receiving 3D ± RBV.

TOPAZ-II was Phase 3b, open-label, non-randomized multi-center trial held in 48 community and academic centers in patients who were treatment-naïve or interferon/RBV treatment-experienced, with or without compensated cirrhosis. Included patients had a creatinine clearance ≥30mL/min, albumin ≥2.8g/dL, and platelet count ≥25 x 109/L.  

Nancy Reau, MD, from the University of Chicago Medical Center, Chicago, IL, and colleagues  analyzed the patients with GT1a infection without cirrhosis that were given 12 weeks of 3D + RBV, and patients with cirrhosis that were given 3D + RBV for 12 or 24 weeks; patients with GT1b infection received 3D ± RBV for 12 weeks.

Of the total 615 patients that received the study drug, 95.3% (586/615) achieved SVR12 with 12 or 24 weeks of treatment with 3D ± RBV (intent-to-treat [ITT] population 95% CI: 93.3, 96.7). “High SVR12 rates were achieved in all patient subgroups examined,” noted Dr. Reau. In the modified ITT (mITT) population, SVR12 rates were 97.3% (95% CI: 95.7, 98.4). 

Five patients (0.8%) experienced on-treatment virologic failure and 11 (1.9%) relapsed by post-treatment Week 12. A total of 6 patients (1.0%) stopped therapy due to adverse events, 4 of which achieved SVR12.

Treatment with 3D ± RBV resulted in high rates of on-treatment response and was well-tolerated in the TOPAZ-II study. Study patients will be followed for 5 years post-treatment to assess the long-term effect of SVR12 on progression of liver disease, added Dr. Reau.