What is the dosage and usage of Apixaban (apixaban) by patient age?

From the Guidelines

Apixaban dosing should be adjusted based on age, with patients aged 80 years or older receiving a reduced dose of 2.5 mg twice daily, as recommended by the 2024 ESC guidelines for the management of atrial fibrillation 1. When considering apixaban therapy, age is a critical factor in determining the appropriate dose.

• For most adults with atrial fibrillation, the standard dose is 5 mg twice daily.
• However, patients aged 80 years or older should receive a reduced dose of 2.5 mg twice daily, especially when they also have low body weight (≤60 kg) or elevated serum creatinine (≥133 mmol/L), as these factors increase the risk of bleeding complications.
• The dose reduction is crucial because elderly patients have increased risk of bleeding complications due to age-related changes in kidney function, decreased body mass, and altered drug metabolism.
• For patients under 80 years without other risk factors, the standard dose remains appropriate regardless of age. Key considerations for apixaban dosing in elderly patients include:
• Regular monitoring of renal function, as declining kidney function may necessitate dose adjustments 1.
• Assessment for fall risk and potential drug interactions that could increase bleeding risk while on apixaban therapy.
• The 2024 ESC guidelines emphasize that the standard full dose should be used to provide optimal prevention of thromboembolism related to AF, unless specific criteria for dose reduction are met 1.

From the FDA Drug Label

The recommended dose of apixaban tablets for most patients is 5 mg taken orally twice daily. The recommended dose of apixaban tablets is 2.5 mg twice daily in patients with at least two of the following characteristics:

• age greater than or equal to 80 years
• body weight less than or equal to 60 kg
• serum creatinine greater than or equal to 1.5 mg/dL

Dosing by Age:

• For patients greater than or equal to 80 years, the recommended dose is 2.5 mg twice daily if they have at least one other characteristic (body weight less than or equal to 60 kg or serum creatinine greater than or equal to 1.5 mg/dL).
• For patients less than 80 years, the recommended dose is 5 mg twice daily. 2

From the Research

Apixaban Dosage by Age

• The dosage of apixaban may need to be adjusted based on age, with older patients potentially requiring a lower dose 3, 4.
• A study found that 29% of patients with atrial fibrillation and recent acute heart failure would have needed apixaban dosage adjustment during follow-up, with a higher proportion of patients with advanced age (≥ 75 years) requiring adjustment 3.
• Another study found that age was an independent predictor for apixaban underdosage, with older patients being more likely to receive an inappropriate dose reduction 4.

Renal Function and Apixaban Dosage

• Renal impairment and fluctuations in renal function are common in patients with atrial fibrillation and heart failure, and may affect apixaban dosing 3.
• A study found that apixaban appears to be a reasonable alternative to warfarin in patients with severe renal impairment, with similar efficacy and safety profiles 5.
• Another study found that apixaban may be associated with lower risks of adverse renal outcomes compared to warfarin, although the relationship was not statistically significant 6.

Safety and Efficacy of Apixaban in Older Patients

• A systematic review found that apixaban has similar efficacy and a somewhat superior safety profile to warfarin in patients with stage 4 and 5 chronic kidney disease, including older patients 7.
• The review suggested that apixaban may be considered a reasonable alternative to warfarin in these patients, although more randomized controlled trials are needed to add to the evidence 7.