What is Eliquis (apixaban) used for?

Eliquis (Apixaban) Indications

Eliquis (apixaban) is FDA-approved for five primary indications: stroke prevention in nonvalvular atrial fibrillation, VTE prophylaxis after hip/knee replacement surgery, treatment of deep vein thrombosis, treatment of pulmonary embolism, and reduction of recurrent VTE risk following initial therapy. 1

FDA-Approved Indications

The official FDA labeling specifies the following uses 1:

• Stroke prevention in nonvalvular atrial fibrillation: Reduces risk of stroke and systemic embolism in patients with AF not caused by heart valve disease
• VTE prophylaxis post-orthopedic surgery: Prevents deep vein thrombosis (which may lead to pulmonary embolism) following hip or knee replacement
• Acute VTE treatment: Treats both deep vein thrombosis and pulmonary embolism
• Secondary VTE prevention: Reduces recurrence risk after completing initial anticoagulation therapy

Mechanism and Pharmacology

Apixaban is an oral direct factor Xa inhibitor that blocks both free and clot-bound factor Xa activity 2. Key pharmacologic features include:

• Bioavailability: Approximately 45-50% oral bioavailability 2, 3
• Peak levels: 3-4 hours after administration 2, 3
• Half-life: 8-14 hours, allowing twice-daily dosing 2
• Elimination: Multiple pathways including hepatic metabolism (CYP3A4-dependent), biliary excretion, and direct intestinal excretion; only ~25-27% renal clearance 2, 4

This lower renal dependence compared to other DOACs (dabigatran ~80%, rivaroxaban ~33%) makes apixaban particularly suitable for patients with moderate renal impairment 5, 4.

Atrial Fibrillation: Evidence Base

For stroke prevention in nonvalvular AF, apixaban demonstrates superiority over both warfarin and aspirin with improved safety profiles. 6

ARISTOTLE Trial (vs. Warfarin)

The landmark ARISTOTLE trial enrolled 18,201 patients with AF and mean CHADS₂ score of 2.1 6. Apixaban 5 mg twice daily (or 2.5 mg twice daily for patients with ≥2 dose-reduction criteria) showed:

• Efficacy: Significantly fewer strokes/systemic emboli (1.27%/year vs 1.60%/year; HR 0.79, P=0.01 for superiority) 6
• Safety: Significantly less major bleeding (2.13%/year vs 3.09%/year; HR 0.69) 6
• Mortality benefit: Fewer deaths than warfarin—the first DOAC to demonstrate survival advantage 6, 7
• Intracranial hemorrhage: Markedly reduced (0.24%/year vs 0.47%/year) 6, 8

The benefit was consistent regardless of prior stroke, CHADS₂ score, or renal function 6.

AVERROES Trial (vs. Aspirin)

In 5,599 patients deemed unsuitable for warfarin, apixaban proved superior to aspirin 9, 6, 8:

• Efficacy: 55% reduction in stroke/systemic embolism (1.6%/year vs 3.7%/year; HR 0.45) 9, 8
• Safety: Similar major bleeding rates (1.4%/year vs 1.2%/year) 8
• Trial terminated early due to clear superiority 6

Dosing in Atrial Fibrillation

Standard dose: 5 mg twice daily 9, 6

Reduced dose: 2.5 mg twice daily if ≥2 of the following criteria 9, 6, 5:

• Age ≥80 years
• Body weight ≤60 kg
• Serum creatinine ≥1.5 mg/dL

Renal considerations 9, 5:

• CrCl >50 mL/min: 5 mg twice daily
• CrCl 30-49 mL/min: 5 mg twice daily (consider 2.5 mg if dose-reduction criteria met)
• CrCl 15-29 mL/min: Very limited data; avoid if possible
• CrCl <15 mL/min: Not recommended 9

VTE Prevention After Orthopedic Surgery

Apixaban 2.5 mg twice daily starting 12-24 hours post-surgery demonstrates superiority over enoxaparin for thromboprophylaxis 2:

ADVANCE Trials

• ADVANCE-2 (knee arthroplasty): Superior to enoxaparin 40 mg daily for VTE prevention (15.1% vs 24.4%; RR 0.62, P<0.0001) 2
• ADVANCE-3 (hip arthroplasty): Superior to enoxaparin 40 mg daily (1.4% vs 3.9%; RR 0.36, P<0.001) 2
• Bleeding: Numerically lower bleeding rates than enoxaparin across trials 2

Duration: 10-14 days for knee replacement; 35 days for hip replacement 2

VTE Treatment and Secondary Prevention

For acute VTE treatment, apixaban is noninferior to enoxaparin/warfarin with significantly less bleeding. 4

AMPLIFY Trial

The AMPLIFY trial compared apixaban (10 mg twice daily for 7 days, then 5 mg twice daily for 6 months) versus conventional therapy (enoxaparin followed by warfarin) 4:

• Efficacy: Noninferior for recurrent VTE/VTE-related death (2.3% vs 2.7%; RR 0.84) 4
• Safety: Superior—significantly less major bleeding (0.6% vs 1.8%; RR 0.31, P<0.001) 4

Extended VTE Prevention

For patients completing 6-12 months of anticoagulation, extended apixaban significantly reduced recurrent VTE versus placebo 4. The 2020 ASH guidelines support apixaban as a preferred option for VTE treatment 10.

Important Contraindications and Warnings

Absolute Contraindications 1

• Active pathological bleeding
• Severe hypersensitivity reaction to apixaban
• Prosthetic heart valves 6

Black Box Warnings 1

Discontinuation risk: Stopping apixaban in AF patients increases stroke risk. Never discontinue without alternative anticoagulation unless absolutely necessary 1.

Spinal/epidural hematoma risk: Patients receiving neuraxial anesthesia or spinal puncture face risk of permanent paralysis. Monitor closely for neurological symptoms (tingling, numbness, muscle weakness) 1.

Bleeding risk: Can cause serious, potentially fatal bleeding. Higher risk with concomitant antiplatelet agents, NSAIDs, SSRIs/SNRIs, or other anticoagulants 1.

Drug Interactions

Avoid strong dual inhibitors of CYP3A4 and P-glycoprotein (ketoconazole, ritonavir) as they significantly increase apixaban levels 2.

Caution with antiplatelet therapy: The safety of combining apixaban with antiplatelet agents is not well-established 9. In acute coronary syndrome, apixaban added to dual antiplatelet therapy resulted in unacceptably high bleeding rates 4.

Special Populations

Cancer Patients

Current guidelines do not recommend apixaban for VTE prophylaxis or treatment in cancer patients due to insufficient data 4. Only 2.7% of AMPLIFY trial participants had cancer 4.

Renal Impairment

Apixaban's predominantly non-renal elimination (73% hepatic/intestinal) makes it advantageous in moderate renal dysfunction 5, 4. Patients with CrCl 30-50 mL/min showed consistent efficacy and safety in ARISTOTLE 6, 5.

Hepatic Impairment

Avoid in patients with transaminases >2× upper limit of normal or total bilirubin >1.5× upper limit of normal 4.

Medically Ill Patients

The ADOPT trial showed extended thromboprophylaxis with apixaban was NOT superior to shorter enoxaparin courses in acutely ill medical patients and caused more major bleeding 2. Do not use apixaban for extended medical thromboprophylaxis.