This study is divided into two parts.~The first part is a multiple dose pharmacokinetic and pharmacodynamics study of Apixaban in patient with stable renal function. The primary purpose of this study is to provide a clear understanding of the effect of creatinine clearance on pharmacokinetics and pharmacodynamics of Apixaban among Thai patients with nonvalvular atrial fibrillation. To assess the pharmacokinetics and pharmacodynamics of Apixaban, This study will enroll 30 subjects who meet the inclusion criteria.~The second part of this study will retrospectively determine the occurrent of clinical outcome between patients who were prescribed apixaban dose concordant and discordant to the drug leaflet. A total of 241 subjects will be recruited. The follow up period will begin from the time of initiation of apixaban until occurrent of stoke, transient ischemic attack, systemic embolism, bleeding, or death.
The purpose of this study is to assess pharmacokinetics and pharmacodynamics of Apixaban and clinical outcome of Apixaban in Thai patients with nonvalvular atrial fibrillation with varying degree of creatinine clearance