IDX184: Phase IIb data

A double-blind, international Phase IIb trial in 67 treatment-naïve patients with HCV genotype 1 infection showed that once-daily 50 and 100 mg IDX184 plus pegylated interferon and ribavirin for 12 weeks showed no evidence of severe cardiac findings as evaluated by multiple cardiac safety measurements, including electrocardiograms, echocardiograms and levels of the cardiac biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP) and ultra-sensitive troponins. Additionally, 76% of patients in the low-dose IDX184 arm and 82% of patients in the high-dose IDX184 arm achieved a complete early virologic response (cEVR) defined as undetectable HCV RNA levels (<25 IU/mL) at week 12. Furthermore, 53% of patients receiving low-dose IDX184 and 55% of patients receiving high-dose IDX184 achieved a rapid virologic response (RVR) at week 4. No patient experienced viral breakthrough during the 12-week treatment period. However, 2 patients with the interleukin-28B (IL-28B; IFNL3) genotype experienced virologic rebound during the pegylated interferon and ribavirin extension phase of the trial.

Patients who achieved an extended rapid virologic response (eRVR), defined as undetectable HCV RNA levels at both weeks 4 and 12, were randomized to stop treatment after an additional 12 or 36 weeks of pegylated interferon and ribavirin in the extended treatment phase. Patients who did not achieve an eRVR entered the 36-week pegylated interferon and ribavirin extended treatment phase. Data were presented at the American Association for the Study of Liver Diseases meeting in Boston. Idenix said complete SVR data from the trial will be reported next year. The company reported interim data from the first cohort of 31 patients in the trial in June (see BioCentury, June 25). ...