What is the recommended protocol for converting a patient from warfarin (Coumadin) to Eliquis (apixaban)?

Protocol for Converting from Warfarin to Eliquis (Apixaban)

When converting a patient from warfarin (Coumadin) to Eliquis (apixaban), discontinue warfarin and start apixaban when the International Normalized Ratio (INR) is below 2.0. 1

Conversion Process

• Discontinue warfarin and begin monitoring the INR 1
• Start apixaban when the INR falls below 2.0 1
• No bridging therapy with heparin or low-molecular-weight heparin (LMWH) is generally required during the transition from warfarin to apixaban 1
• Begin with the standard dosing of apixaban based on the indication:
  • For nonvalvular atrial fibrillation: 5 mg twice daily (or 2.5 mg twice daily for patients with at least two of the following: age ≥80 years, body weight ≤60 kg, or serum creatinine ≥1.5 mg/dL) 1
  • For DVT/PE treatment: 10 mg twice daily for 7 days, followed by 5 mg twice daily 1
  • For DVT/PE recurrence prevention: 2.5 mg twice daily after at least 6 months of treatment 1

Special Considerations

• For patients with mechanical heart valves, conversion to apixaban is contraindicated - these patients should remain on warfarin therapy 2
• For patients with end-stage chronic kidney disease (CrCl <15 mL/min) or on hemodialysis, warfarin is preferred over apixaban 2
• For patients with moderate-to-severe chronic kidney disease (CrCl 15-30 mL/min), apixaban may be considered with appropriate dose adjustment, as it has shown favorable bleeding profiles compared to warfarin in patients with CrCl 25-30 mL/min 3
• If the patient is taking combined P-glycoprotein (P-gp) and strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir), reduce the apixaban dose by 50% when transitioning from warfarin 1

Monitoring After Conversion

• Unlike warfarin, routine INR monitoring is not required for patients on apixaban 2
• Assess renal function before initiating apixaban and periodically during treatment, especially in elderly patients 2
• Evaluate bleeding risk factors and reassess the need for anticoagulation at regular intervals 2

Temporary Interruption for Procedures

• If a procedure is planned, apixaban should be discontinued:
  • At least 48 hours prior to elective surgery or invasive procedures with moderate or high risk of bleeding 1
  • At least 24 hours prior to procedures with low risk of bleeding 1
• Restart apixaban as soon as adequate hemostasis has been established 1

Common Pitfalls to Avoid

• Do not use a loading dose when initiating apixaban after warfarin discontinuation 1
• Avoid simultaneous administration of warfarin and apixaban, as apixaban can affect INR measurements and interfere with warfarin dosing 1
• Do not use apixaban in patients with mechanical heart valves, as direct thrombin inhibitors and factor Xa inhibitors are not recommended for this population 2
• For patients who miss a dose of apixaban, take it as soon as possible on the same day and resume the twice-daily schedule; do not double the dose to make up for a missed dose 1