Evaluation of the Pharmacokinetics and Safety of a Single Oral Dose of Fasiglifam in Subjects with Mild or Moderate Hepatic Impairment

Background and Aims Fasiglifam, a potent, selective novel agonist of G protein-coupled receptor 40, stimulates insulin secretion at elevated blood glucose levels in a glucose-dependent manner. This study evaluated the potential effect of hepatic impairment on the pharmacokinetics and safety of a single dose of fasiglifam and its metabolite M-I. Fasiglifam's clinical development was halted due to liver safety concerns. Methods In this phase I, open-label study, subjects with mild or moderate hepatic impairment, along with matched controls (gender, weight, age, and smoking status), received a single, 25-mg oral dose of fasiglifam. Blood samples were collected through 336 h post-dose for pharmacokinetic evaluation. Results Overall, 73% of subjects were male with a mean age of 54 years. Compared with normal hepatic function subjects (n = 14), mean systemic fasiglifam exposure (C-max and AUC(infinity)) was reduced in mild (n = 8) and moderate (n = 8) hepatic impairment subjects by approximately 20-40%. However, the observed percent unbound drug plasma concentration appeared comparable across all groups. Mean oral clearance was higher and terminal half-life lower in subjects with mild or moderate hepatic impairment compared with normal hepatic function subjects. Fasiglifam M-I systemic exposure increased by approximately twofold in subjects with mild or moderate hepatic impairment compared with those with normal hepatic function. Fasiglifam was well tolerated, and there were no reports of hypoglycemia. Conclusion Hepatic status did not significantly impact systemic exposure of fasiglifam in this study, in fact, a decrease was observed, suggesting no dose reduction would be required for patients with hepatic impairment.