Safety and efficacy of faldaprevir in combination with pegylated interferon α-2b and ribavirin in Japanese patients with genotype-1 chronic hepatitis C virus infection. 
We evaluated the safety and efficacy of the hepatitis C virus (HCV) NS3/4A A protease inhibitor faldaprevir plus pegylated interferon α-2b and ribavirin (PegIFNα-2b/RBV) in Japanese patients with HCV genotype-1 infection.  Treatment-naïve patients were randomized (1:1) to faldaprevir 120 mg q.d.  for 12 or 24 weeks (response-guided therapy [RGT], n = 44), or faldaprevir 240 mg q.d.  for 12 weeks (n = 43), each combined with PegIFNα-2b/RBV for 24 or 48 weeks (RGT).  Response-guided therapy was based on early treatment success (HCV RNA <25 IU/mL at week 4 and <25 IU/mL undetected at week 8).  Treatment-experienced patients received 240 mg q.d.  for 24 weeks, plus PegIFNα-2b/RBV RGT (24 or 48 weeks, prior relapsers, n = 29) or PegIFNα-2b/RBV (48 weeks, 5 prior partial responders/breakthroughs, 10 prior null responders).  The primary objective was safety; sustained virologic response 12 weeks post-treatment (SVR12) was a secondary end-point.  All except one patient experienced drug-related adverse events.  Adverse events led to faldaprevir discontinuation in 1 (2%), 13 (20%), and 3 (6.8%) patients on faldaprevir 120 mg, faldaprevir 240 mg 12 weeks, and faldaprevir 240 mg 24 weeks, respectively.  The SVR12 rates were: 86% with faldaprevir 120 mg and 74% with faldaprevir 240 mg among treatment-naïve patients; and 86%, 60%, and 40% among prior relapsers, partial responders/breakthroughs, and null responders, respectively.  In treatment-naïve Japanese patients, faldaprevir 120 mg q.d.  plus PegIFNα-2b/RBV was better tolerated than faldaprevir 240 mg q.d.  plus PegIFNα-2b/RBV, with at least comparable efficacy.  In treatment-experienced patients, most prior relapsers achieved SVR12 with 24 weeks of faldaprevir 240 mg q.d.  plus PegIFNα-2b/RBV.  Clinicaltrials.gov NCT01579474.