Edoxaban

• Atrial Fibrillation Stroke Prevention
• Deep Vein Thrombosis
• Pulmonary Embolism
• Anticoagulation Therapy

Edoxaban is a direct factor Xa inhibitor oral anticoagulant used for the prevention of stroke in atrial fibrillation and treatment of venous thromboembolism. This once-daily medication offers predictable anticoagulation without routine monitoring and has a unique dosing consideration based on renal function.

Mechanism of Action

Edoxaban is a selective, reversible direct inhibitor of factor Xa, a serine protease that plays a central role in the coagulation cascade. Factor Xa is positioned at the convergence of the intrinsic and extrinsic coagulation pathways and catalyzes the conversion of prothrombin to thrombin. One molecule of factor Xa can generate over 1000 molecules of thrombin, making it an attractive target for anticoagulation. By inhibiting factor Xa, edoxaban reduces thrombin generation and subsequent fibrin clot formation. Unlike warfarin, edoxaban provides rapid onset of action, predictable pharmacokinetics, and does not require routine INR monitoring.

Available Formulations

Edoxaban is available as oral tablets in 15 mg, 30 mg, and 60 mg strengths. The tablets can be taken with or without food. For patients who cannot swallow tablets whole, edoxaban tablets may be crushed and mixed with water or applesauce and administered immediately by mouth or through a gastric tube.

Medical Uses

Edoxaban is FDA-approved for reduction of stroke and systemic embolism risk in patients with non-valvular atrial fibrillation (NVAF) and for treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE) following 5-10 days of initial therapy with a parenteral anticoagulant. Uniquely, edoxaban should NOT be used in NVAF patients with CrCl greater than 95 mL/min because efficacy was reduced in this subgroup in the ENGAGE AF-TIMI 48 trial, possibly due to lower drug exposure.

Dosing Guidelines

For NVAF (in patients with CrCl 15-95 mL/min), the dose is 60 mg once daily. The dose is reduced to 30 mg once daily for CrCl 15-50 mL/min, body weight ≤60 kg, or concurrent use of certain P-gp inhibitors. For DVT/PE treatment, the dose is 60 mg once daily following 5-10 days of parenteral anticoagulation, with dose reduction to 30 mg daily for the same factors. Edoxaban should not be used in NVAF patients with CrCl >95 mL/min.

Important Safety Information

Edoxaban carries a boxed warning regarding reduced efficacy in NVAF patients with CrCl >95 mL/min (use another anticoagulant), premature discontinuation increasing stroke risk, and spinal/epidural hematoma risk with neuraxial anesthesia. Major bleeding is the primary risk; idarucizumab is not effective for edoxaban reversal, but andexanet alfa may be used. The medication should be discontinued 24 hours before invasive procedures with moderate or high bleeding risk. Mechanical heart valves and moderate to severe mitral stenosis are contraindications.

Drug Interactions

P-glycoprotein (P-gp) inhibitors may increase edoxaban exposure. The dose should be reduced to 30 mg daily when used with certain P-gp inhibitors (dronedarone, cyclosporine, erythromycin, ketoconazole, azithromycin). Rifampin (a P-gp inducer) significantly reduces edoxaban levels and concurrent use should be avoided. NSAIDs, antiplatelet agents, and other anticoagulants increase bleeding risk. Edoxaban does not significantly interact with CYP3A4 inhibitors or inducers.

Special Populations

There are no adequate studies in pregnant women. Based on mechanism, bleeding is expected at delivery if used during pregnancy. Breastfeeding is not recommended during treatment. Safety and efficacy have not been established in pediatric patients. Elderly patients may have increased drug exposure due to reduced renal function. Dose adjustment is required for moderate renal impairment (CrCl 15-50 mL/min); the medication is not recommended for CrCl <15 mL/min or dialysis. No dose adjustment is needed for hepatic impairment, but use is not recommended in moderate or severe impairment.