Dabigatran may be a cost-effective alternative to warfarin for stroke prevention in atrial fibrillation

The recently FDA-approved oral direct thrombin inhibitor, dabigatran, may be cost-effective compared to the standard-of-care therapy of adjusted-dose warfarin in patients requiring anticoagulation for stroke prevention in atrial fibrillation, according to a pharmacoeconomic evaluation published in the Annals of Internal Medicine.

Key Points

The first-in-class and recently FDA-approved oral direct thrombin inhibitor, dabigatran, may be cost-effective compared to the standard-of-care therapy of adjusted-dose warfarin in patients requiring anticoagulation for stroke prevention in atrial fibrillation (AF), according to a pharmacoeconomic evaluation published in the Annals of Internal Medicine.

AF has been estimated to affect as many as 2.3 million Americans, including 10% of adults aged >80 years, making it the second most common cardiovascular condition in the United States.

To evaluate the cost-effectiveness of dabigatran compared to adjusted-dose warfarin [with a target international normalized ratio (INR) of 2 to 3] over an AF patient's lifetime (starting at age 65), researchers conducted a Markov decision model utilizing clinical data from the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) trial and cost data from the US Federal government including the Centers for Medicare & Medicaid Services (CMS) and the Agency for Healthcare Research and Quality (AHRQ).

The researchers explained in their paper, "Warfarin is a generic medication and prescription costs are low, but the costs of laboratory monitoring and complications due to over- and under-anticoagulation are substantial."

Sensitivity-or what if?-analyses were also conducted by the researchers in order to determine what effect the cost of dabigatran and patients' stroke risk would have on the evaluation's overall conclusions. These analyses suggested their conclusions were "sensitive" to the cost of dabigatran, with the incremental cost-effectiveness ratio estimated to be above the $50,000/QALY gained threshold when dabigatran cost was at or above $13.70 per day. Furthermore, the cost-effectiveness of dabigatran improved with increasing patient risk for stroke (higher CHADS2 score) and intracranial hemorrhage.