Rationale and design of the Affordability and Real-world Antiplatelet Treatment Effectiveness after Myocardial Infarction Study (ARTEMIS): A multicenter, cluster-randomized trial of P2Y₁₂ receptor inhibitor copayment reduction after myocardial infarction

Background The use of oral P2Y₁₂ receptor inhibitors after acute myocardial infarction (MI) can reduce risks of subsequent major adverse cardiovascular events (composite of all-cause death, recurrent MI, and stroke), yet medication persistence is suboptimal. Although copayment cost has been implicated as a factor influencing medication persistence, it remains unclear whether reducing or eliminating these costs can improve medication persistence and/or downstream clinical outcomes. Design ARTEMIS is a multicenter, cluster-randomized clinical trial designed to examine whether eliminating patient copayment for P2Y₁₂ receptor inhibitor therapy affects medication persistence and clinical outcomes. We will enroll approximately 11,000 patients hospitalized for acute ST-elevation and non-ST-elevation MI at 300 hospitals. Choice and duration of treatment with a P2Y₁₂ receptor inhibitor will be determined by the treating physician. Hospitals randomized to the copayment intervention will provide vouchers to cover patients' copayments for their P2Y₁₂ receptor inhibitor for up to 1 year after discharge. The coprimary end points are 1-year P2Y₁₂ receptor inhibitor persistence and major adverse cardiovascular events. Secondary end points include choice of P2Y₁₂ receptor inhibitor, patient-reported outcomes, and postdischarge cost of care. Conclusion ARTEMIS will be the largest randomized assessment of a medication copayment reduction intervention on medication persistence, clinical outcomes, treatment selection, and cost of care after acute MI.