Apixaban in End-stage Kidney Disease : A Pharmacokinetics Study

Apixaban is a novel oral direct factor Xa inhibitor; In patients with atrial fibrillation, apixaban was superior to warfarin in preventing stroke or systemic embolism, caused less bleeding, and resulted in lower mortality (the ARISTOTLE trial). Given its favorable outcome profile compared to oral vitamin K antagonists in patients with normal kidney function and in patients with mild to moderate kidney disease and given the potential serious side-effects of oral vitamin K antagonists in end-stage kidney disease, apixaban may be an attractive alternative for systemic anticoagulation in dialysis patients. The pharmacokinetics of apixaban in end-stage renal disease is not well characterized. The aim of the current study is to perform single dose pharmacokinetics / pharmacodynamics studies in patients treated with end-stage renal disease. The primary aim is to determine inter-dialytic pharmacokinetics of Apixaban, secondary aims are intra-dialytic pharmacokinetics and dose finding. Two doses of drugs will be studies (2.5 mg and 5 mg). Study drug will be administered at the end of a dialysis session (part A) and at the beginning of a dialysis session (Part B). Six (n=6) patients are scheduled to be included for each part and each dose. Anti-Xa activity values (IIU/mL) will be converted to apixaban concentration data (ng/mL). Apixaban concentration-time profiles will be generated and observed values for the descriptive PK parameters Cmax (peak plasma concentration) and time to Cmax (Tmax) will be determined directly from these profiles. PK profiles will be further analyzed with non-compartmental analysis (NCA).