Drug Name
Generic Name
Apixaban
Brand Name(s)
- Pakistan: Eliquis
- India: Eliquis
- US: Eliquis
- UK: Eliquis
Pharmacological Class
Class
Anticoagulant
Subclass
Factor Xa inhibitor
Mechanism of Action
Apixaban selectively inhibits Factor Xa, an essential component in the coagulation cascade. By inhibiting Factor Xa, apixaban reduces thrombin generation and blood clot formation.
Indications
Primary Indications
Prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation; treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE); reduction in the risk of recurrent DVT and PE following initial therapy.
Off-label Uses
May be used off-label for thromboprophylaxis in cancer patients or in those with mechanical heart valves, although further studies are needed to confirm efficacy and safety.
Dosage and Administration
Standard Dosage
The typical dosage is 5 mg taken orally twice daily. Dosage may be adjusted to 2.5 mg twice daily in patients with at least two of the following characteristics: age ≥80 years, body weight ≤60 kg, or serum creatinine ≥1.5 mg/dL.
Route of Administration
Oral
Special Populations
- Pediatric: Safety and efficacy have not been established.
- Geriatric: Dosage adjustments may be necessary based on renal function and body weight.
Pharmacokinetics
Absorption
Apixaban is rapidly absorbed, with peak plasma concentrations occurring 3 to 4 hours after oral administration.
Distribution
Approximately 87% plasma protein bound.
Metabolism
Metabolized primarily by CYP3A4/5 and to a lesser extent by CYP1A2, CYP2C8, CYP2C9, CYP2C19, and CYP2J2.
Excretion
Eliminated through multiple pathways, including renal and biliary excretion of metabolites. Approximately 27% is excreted unchanged in the urine.
Half-life
Approximately 12 hours.
Contraindications
Apixaban is contraindicated in patients with active pathological bleeding, severe hypersensitivity to apixaban or any component of the formulation, and in those with hepatic disease associated with coagulopathy and clinically relevant bleeding risk.
Warnings and Precautions
Patients taking apixaban should be monitored for signs of bleeding. Caution is advised in patients undergoing spinal/epidural anesthesia or puncture due to risk of hematoma. Discontinuation of apixaban places patients at increased risk of thrombotic events; coverage with an alternative anticoagulant should be considered if apixaban must be discontinued for reasons other than pathological bleeding or completion of a course of therapy.
Side Effects
Common Side Effects
Bleeding, anemia, nausea, and minor bruising.
Serious Side Effects
Severe bleeding (including gastrointestinal and intracranial bleeding), hypersensitivity reactions, thrombocytopenia.
Drug Interactions
Major Interactions
Strong inhibitors of both CYP3A4 and P-gp (e.g., ketoconazole, ritonavir) can increase apixaban exposure and the risk of bleeding. Concurrent use should be avoided.
Moderate Interactions
Moderate CYP3A4 and P-gp inhibitors (e.g., diltiazem, erythromycin) may increase apixaban exposure, and dose adjustment may be needed.
Minor Interactions
Other anticoagulants, antiplatelet agents, NSAIDs, and SSRIs/SNRIs may increase the risk of bleeding.
Pregnancy and Lactation
Pregnancy Category
Category B: No adequate and well-controlled studies in pregnant women. Apixaban should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Breastfeeding Considerations
It is not known whether apixaban is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when apixaban is administered to a nursing woman.
Patient Counseling Information
Patients should be informed about the importance of adherence to prescribed doses, potential side effects, and the need for regular follow-up visits. Patients should be advised to avoid activities that may increase the risk of injury, and to report any signs of bleeding or unusual bruising to their healthcare provider immediately. Additionally, patients should be made aware of the potential for drug-drug and drug-food interactions and to consult their healthcare provider before taking any new medications or supplements.