From the Guidelines
Oral anticoagulants are classified into two main types: vitamin K antagonists and direct oral anticoagulants (DOACs), with DOACs being the preferred choice for most indications due to their lower bleeding risk and more convenient administration. The two main types of oral anticoagulants are:
- Vitamin K antagonists, which include warfarin (Coumadin) and require regular INR monitoring with typical therapeutic ranges of 2-3 for most indications 1
- Direct oral anticoagulants (DOACs), which include direct thrombin inhibitors like dabigatran (Pradaxa) and factor Xa inhibitors such as rivaroxaban (Xarelto), apixaban (Eliquis), edoxaban (Savaysa), and betrixaban (Bevyxxa) 1
DOACs offer more predictable anticoagulation without routine monitoring requirements and have been shown to reduce the risk of stroke or systemic embolism, all-cause mortality, and intracranial bleeding compared to warfarin 1. The dosing of DOACs varies by indication and patient factors, with typical dosing being:
- Apixaban: 5mg twice daily
- Rivaroxaban: 20mg daily with food
- Dabigatran: 150mg twice daily
- Edoxaban: 60mg daily
Patient-specific factors like renal function, age, weight, drug interactions, and cost considerations influence anticoagulant selection 1. While warfarin remains the only option for mechanical heart valves and severe kidney disease, DOACs are preferred for most other indications due to their lower bleeding risk, particularly intracranial hemorrhage, and more convenient administration without dietary restrictions or frequent monitoring 1.
Key considerations for the use of DOACs include:
- Renal function: DOACs are contraindicated in patients with severe renal insufficiency (creatinine clearance <15 mL/min) 1
- Drug interactions: DOACs can interact with other medications, such as antiplatelet agents and other anticoagulants 1
- Cost: DOACs can be more expensive than warfarin, but may be more cost-effective in the long run due to reduced monitoring requirements and lower risk of bleeding complications 1
From the FDA Drug Label
- 1 Increased Risk of Thrombotic Events after Premature Discontinuation
Premature discontinuation of any oral anticoagulant, including XARELTO, in the absence of adequate alternative anticoagulation increases the risk of thrombotic events.
The types of oral anticoagulant agents mentioned in the label include:
- XARELTO (rivaroxaban)
- Warfarin These are the only oral anticoagulant agents directly mentioned in the label 2.
From the Research
Types of Oral Anticoagulant Agents
- Vitamin K antagonists, such as warfarin, have been the traditional anticoagulants of choice for many years 3
- Direct oral anticoagulants (DOACs) have emerged as alternatives to vitamin K antagonists, with several agents available, including dabigatran, rivaroxaban, apixaban, and edoxaban 4, 5
- Non-vitamin K antagonist oral anticoagulants (NOACs) are another category of oral anticoagulants, which include dabigatran, rivaroxaban, apixaban, and edoxaban 5, 6
- DOACs can be further classified into two subcategories:
- Direct anti-Xa inhibitors, such as rivaroxaban, apixaban, and edoxaban, which bind directly to the catalytic site of factor Xa and inhibit both free and prothrombinase-bound factor Xa 7
- Thrombin inhibitors, such as dabigatran, which occupy and inactivate the serine proteolytic pocket of thrombin, preventing thrombin from acting on fibrinogen to produce fibrin 7
Characteristics of Oral Anticoagulant Agents
- DOACs have been found to be at least as safe and effective as vitamin K antagonists in randomized, controlled trials for stroke prevention in atrial fibrillation and the management of venous thromboembolism 3
- NOACs are at least as effective as warfarin, but are more convenient to administer because they can be given in fixed doses without routine coagulation monitoring, and are safer because they are associated with less intracranial bleeding 5
- DOACs have a rapid onset and offset of activity, and predictable dose-response properties, making them a convenient alternative to traditional anticoagulants 4