Gilead Sciences, Inc. (Nasdaq: GILD) today announced topline results from three Phase 3 clinical trials (ION-1, ION-2 and ION-3) evaluating the investigational once-daily fixed-dose combination of the nucleotide analog polymerase inhibitor sofosbuvir (SOF) 400 mg and the NS5A inhibitor ledipasvir (LDV) 90 mg, with and without ribavirin (RBV), for the treatment of genotype 1 chronic hepatitis C virus (HCV) infection.
Across the three studies, 1,952 patients with genotype 1 HCV infection were randomized to receive SOF/LDV with or without RBV for eight, 12 or 24 weeks of therapy. Of these, 1,512 patients were treatment-naïve, 440 were treatment experienced and 224 had compensated cirrhosis.
The intent-to-treat SVR12 rates observed to date in the ION studies are summarized in the table below. Results of the 24-week arms from ION-1 will be available in the first quarter of 2014 and will be presented at a future scientific meeting.
|ION-1|| GT 1 treatment-naïve
(including 15.7 percent(136/865) with cirrhosis)
|SOF/LDV||12 weeks||97.7% (209/214)|
|SOF/LDV + RBV||12 weeks||97.2% (211/217)|
|SOF/LDV||24 weeks||NA (n=217)|
|SOF/LDV + RBV||24 weeks||NA (n=217)|
|ION-2|| GT 1 treatment-experienced
(including 20.0 percent(88/440) with cirrhosis)
|SOF/LDV||12 weeks||93.6% (102/109)|
|SOF/LDV+RBV||12 weeks||96.4% (107/111)|
|SOF/LDV||24 weeks||99.1% (108/109)|
|SOF/LDV+RBV||24 weeks||99.1% (110/111)|
|ION-3||GT 1 treatment-naïve||SOF/LDV||8 weeks||94.0% (202/215)|
|SOF/LDV + RBV||8 weeks||93.1% (201/216)|
|SOF/LDV||12 weeks||95.4% (206/216)|
Of the 1,518 patients randomized to the 12-week arms of ION-1 and to all arms of ION-2 and ION-3, 1,456 patients (95.9 percent) achieved the primary efficacy endpoint of SVR12. Of the 62 patients (4.1 percent) who failed to achieve SVR12, 36 patients (2.4 percent) experienced virologic failure: 35 due to relapse and only one patient due to on-treatment breakthrough (with documented non-compliance). Twenty-six patients (1.7 percent) were lost to follow-up or withdrew consent.