What is the recommended dosing of Xarelto (rivaroxaban) for patients with non-valvular atrial fibrillation?

Rivaroxaban Dosing for Non-Valvular Atrial Fibrillation

For patients with non-valvular atrial fibrillation, rivaroxaban should be dosed at 20 mg once daily with the evening meal for patients with normal renal function (CrCl >50 mL/min), and reduced to 15 mg once daily with the evening meal for those with moderate renal impairment (CrCl 30-49 mL/min). 1, 2

Standard Dosing Recommendations

• Normal renal function (CrCl >50 mL/min): 20 mg once daily with the evening meal 3, 1
• Moderate renal impairment (CrCl 30-49 mL/min): 15 mg once daily with the evening meal 3, 1, 2
• Severe renal impairment (CrCl 15-29 mL/min): Use with caution; 15 mg once daily may be considered but safety and effectiveness have not been well established 3, 1
• End-stage renal disease (CrCl <15 mL/min) or dialysis: Not recommended 1, 2

Renal Function Assessment

Renal function should be assessed:

• Before initiating therapy
• At least annually during treatment
• More frequently in patients with fluctuating renal function 1

The Cockcroft-Gault method should be used for calculating creatinine clearance, as this was the method used in clinical trials 1.

Administration Guidelines

• Rivaroxaban must be taken with food, preferably with the evening meal, to ensure optimal absorption 1, 2
• Missing doses can significantly impact efficacy due to the short half-life of rivaroxaban 3
• No routine coagulation monitoring is required, unlike warfarin 1

Special Considerations

Bleeding Risk

• Patients with high bleeding risk (HAS-BLED score ≥3) should receive the lower dose of 15 mg once daily 3
• Concomitant use of NSAIDs, aspirin, or clopidogrel may increase bleeding risk 2

Drug Interactions

• Avoid concomitant use of strong CYP3A4 and P-glycoprotein inhibitors or inducers 1
• When used with erythromycin (a moderate CYP3A inhibitor) in patients with renal impairment, significant increases in rivaroxaban exposure have been observed 2

Efficacy and Safety

The ROCKET AF trial demonstrated that rivaroxaban was non-inferior to warfarin for prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation 2, 4. Key findings included:

• Similar rates of major and clinically relevant non-major bleeding compared to warfarin 2, 4
• Reduced intracranial hemorrhage and fatal bleeding compared to warfarin 1, 4
• Increased risk of gastrointestinal bleeding 1

Common Pitfalls to Avoid

• Failure to adjust dose based on renal function: Always check CrCl before prescribing 1
• Administration without food: Rivaroxaban bioavailability is significantly reduced when taken on an empty stomach 1
• Inappropriate use in severe renal impairment: Avoid in patients with CrCl <15 mL/min 1, 2
• Overlooking drug interactions: Be vigilant about medications that affect CYP3A4 and P-glycoprotein 1, 2
• Inadequate patient education: Patients must understand the importance of medication adherence and taking with food 3, 1

By following these dosing recommendations and considerations, clinicians can optimize the efficacy and safety of rivaroxaban therapy for stroke prevention in patients with non-valvular atrial fibrillation.