Open-label phase 2 study of faldaprevir, deleobuvir and ribavirin in Japanese treatment-naive patients with chronic hepatitis C virus genotype 1 infection.

AimThe safety and efficacy of the NS3/4A protease inhibitor faldaprevir in combination with the non-nucleoside NS5B polymerase inhibitor deleobuvir and ribavirin in Japanese treatment-naive patients with chronic genotype 1 hepatitis C virus (HCV) infection was evaluated. MethodsIn this multicenter, open-label phase 2 study, patients were assigned to 8weeks of treatment with 80mg (group 1) or 120mg (group 2) faldaprevir once daily (q.d.) in combination with deleobuvir 600mg twice daily and weight-based ribavirin. This was followed by a 24-week treatment with faldaprevir 120mg q.d. in combination with peginterferon--2a and ribavirin. The primary objective was safety; virological response at weeks 4 and 8 was a secondary endpoint. ResultsTwelve and 13 patients were treated in group 1 and 2, respectively; all were infected with HCV genotype 1b. All patients experienced a drug-related adverse event (AE). The frequency of individual events was generally numerically greater in group 2 than 1. The most common AEs were nausea (66.7%, group 1; 76.9%, group 2) and vomiting (33.3%, group 1; 61.5%, group 2). Virological response at weeks 4 and 8 was achieved by 11 (91.7%) patients in group 1; in group 2, 12 (92.3%) patients achieved virological response at week 4 and all at week 8. All patients who achieved the week 8 endpoint achieved sustained virological response at week 12. ConclusionFaldaprevir 80 or 120mg q.d. in combination with deleobuvir and ribavirin was tolerable and had similar efficacy in Japanese patients with HCV genotype 1 infection. ClinicalTrials.gov: NCT01528735.