An Open-Label Investigation into Drug–Drug Interactions Between Multiple Doses of Daclatasvir and Single-Dose Cyclosporine or Tacrolimus in Healthy Subjects

BACKGROUND AND OBJECTIVE: Chronic hepatitis C virus (HCV) infection is a major cause of liver transplantation. Drug–drug interactions (DDIs) with cyclosporine and tacrolimus hindered the use of first-generation protease inhibitors in transplant recipients. The current study investigated DDIs between daclatasvir—a pan-genotypic HCV NS5A inhibitor with clinical efficacy in multiple regimens (including all-oral)—and cyclosporine or tacrolimus in healthy subjects. METHODS: Healthy fasted subjects (aged 18–49 years; body mass index 18–32 kg/m(2)) received single oral doses of cyclosporine 400 mg on days 1 and 9, and daclatasvir 60 mg once daily on days 4–11 (group 1, n = 14), or a single oral dose of tacrolimus 5 mg on days 1 and 13, and daclatasvir 60 mg once daily on days 8–19 (group 2, n = 14). Blood samples for pharmacokinetic analysis [by liquid chromatography with tandem mass spectrometry (LC–MS/MS)] were collected on days 1 and 9 for cyclosporine (72 h), on days 1 and 13 for tacrolimus (168 h) and on days 8 and 9 (group 1) or on days 12 and 13 (group 2) for daclatasvir (24 h). Plasma concentrations were determined by validated LC–MS/MS methods. RESULTS: Daclatasvir did not affect the pharmacokinetic parameters of cyclosporine or tacrolimus, and tacrolimus did not affect the pharmacokinetic parameters of daclatasvir. Co-administration of cyclosporine resulted in a 40 % increase in the area under the concentration–time curve of daclatasvir but did not affect its maximum observed concentration. CONCLUSION: On the basis of these observations in healthy subjects, no clinically relevant DDIs between daclatasvir and cyclosporine or tacrolimus are anticipated in liver transplant recipients infected with HCV; dose adjustments during co-administration are unlikely to be required.