PK of Rivaroxaban in Bariatric Patients - Extension

• Patient with past elective bariatric surgery (Roux-en-Y gastric bypass surgery or sleeve gastrectomy 6-8 months ago)
• Patient aged 18 years and older
• BMI ≥ 35 kg/m2
• Women of child-bearing age: Willingness of using a double barrier contraception method during the study
• Written, informed consent

Exclusion Criteria:

• Intake of oral anticoagulants (phenprocoumon, acenocoumarol, dabigatran, etexilate, apixaban etc.) 4 weeks prior to inclusion in the study
• Application of parenteral anticoagulants (unfractionated heparin, low molecular weight heparins, heparin derivates (fondaparinux etc.) 4 weeks prior to inclusion in the study
• Pharmacologic platelet inhibition 4 weeks prior to inclusion in the study
• Known coagulation disorders (e.g. Willebrand's disease, haemophilia)
• Evidence for deep vein thrombosis or pulmonary embolism in the personal history or in the history of first degree relatives
• Medical condition that is associated with an increased risk for VTE, i.e. active cancer disease, lupus erythematodes chronic inflammatory bowel disease
• Active, clinically significant bleeding
• Congenital or acquired bleeding disorder
• Uncontrolled severe hypertension
• Active gastrointestinal disease that can potentially lead to bleeding disorder: oesophagitis, gastritis, gastroesophageal reflux disease, chronic inflammatory bowel disease
• Vascular retinopathy
• Bronchiectasis or history of pulmonary bleeding
• Prior stroke or TIA
• Hereditary galactose intolerance, Lapp lactase deficiency, glucose-lactose malabsorption
• Severe renal impairment with a creatinine clearance (GFR) of \< 30ml/min
• Positive pregnancy test, pregnancy or nursing women
• High risk of bleeding (e.g. active ulcerative gastrointestinal disease)
• Known intolerance of the study medication rivaroxaban
• Concomitant treatment with strong CYP3A4 inhibitors (e.g. ketoconazole, itraconazole, lopinavir, ritonavir, indinavir)
• Concomitant treatment with an P-glycoprotein inhibitor and weak or moderate CYP3A4 inhibitor (e.g. erythromycin, azithromycin, diltiazem, verapamil, quinidine, ranolazine, dronedarone, amiodarone, felodipine)