The nephrotic syndrome (NS) is characterized by proteinuria and hypoalbuminemia, and patients with nephrotic syndrome are known to be hypercoaguable with increased incidence of venous thromboembolism necessitating anticoagulation. While classically warfarin has been used as an anticoagulant in NS, newer oral anticoagulants, such as apixaban, are increasingly used to treat venous thromboembolism (VTE) in the general population. It is unknown how hypoalbuminemia and proteinuria affect the pharmacokinetics and pharmacodynamics of apixaban. This study is to investigate the pharmacokinetics and pharmacodynamics of apixaban in nephrotic syndrome.