Impact of adherence on the cost-effectiveness of apixaban and rivaroxaban in stroke prevention among patients with atrial fibrillation in the United States.

Abstract

Objective: Despite the beneficial effects of DOACs, suboptimal adherence is widely documented, and real-world adherence is lower than in clinical trials. The objective of this study is to compare the cost-effectiveness of apixaban versus rivaroxaban for stroke prevention by incorporating real-world adherence from the US payer's perspective.

Methods: We developed a Markov model with three health states to evaluate the total costs and quality-adjusted life years (QALY) at a willingness to pay threshold of $100,000. The population was a hypothetical cohort of 65-year-old patients with moderate to high stroke risk. The transition probabilities of healthy adherent, nonadherent, and stroke were obtained from a Medicare Advantage Plan. The utilities and costs were obtained from prior clinical studies. Deterministic and probabilistic sensitivity analyses were conducted.

Results: Apixaban was cost-effective than rivaroxaban at a willingness to pay threshold of $100,000. Apixaban yielded an additional 0.12 QALYs at a cost of $1904.39, resulting in an incremental cost-effectiveness ratio (ICER) of $16,279.25 per QALY gained. The Monte Carlo simulations indicated that apixaban was cost-effective at 89.67% of simulations. The ICER results were impacted by the medical costs among nonadherent patients.

Conclusion: After incorporating adherence, apixaban 5 mg was a cost-effective alternative to rivaroxaban 20 mg for stroke prevention among elderly atrial fibrillation (AF) patients.