Background Persistence to P2Y12 inhibitors after myocardial infarction (MI) remains low. Out-of-pocket cost is cited as a factor affecting medication compliance. We examined whether a copayment intervention affected 1-year persistence to P2Y12 inhibitors and clinical outcomes. Methods and Results In an analysis of ARTEMIS (Affordability and Real-World Antiplatelet Treatment Effectiveness After Myocardial Infarction Study), patients with MI discharged on a P2Y12 inhibitor were stratified by baseline out-of-pocket medication burden: low ($0-$49 per month), intermediate ($50-$149 per month), and high (≥$150 per month). The impact of the voucher intervention on 1-year P2Y12 inhibitor persistence was examined using a logistic regression model with generalized estimating equations. We assessed the rates of major adverse cardiovascular events among the groups using a Kaplan-Meier estimator. Among 7351 MI-treated patients at 282 hospitals, 54.2% patients were in the low copay group, 32.0% in the middle copay group, and 13.8% in the high copay group. Patients in higher copay groups were more likely to have a history of prior MI, heart failure, and diabetes compared with the low copay group (all P<0.0001). Voucher use was associated with a significantly higher likelihood of 1-year P2Y12 inhibitor persistence regardless of copayment tier (low copay with versus without voucher: adjusted odds ratio [OR], 1.44 [95% CI, 1.25-1.66]; middle copay: adjusted OR, 1.63 [95% CI, 1.37-1.95]; high copay group: adjusted OR, 1.41 [95% CI, 1.05-1.87]; P interaction=0.42). Patients in the high copay group without a voucher had similar risk of 1-year major adverse cardiovascular events compared with patients in the high copay group with a voucher (adjusted hazard ratio, 0.89 [95% CI, 0.66-1.21]). Conclusions Medication copayment vouchers were associated with higher medication persistence at 1 year following an MI, regardless of out-of-pocket medication burden. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02406677.

Background Hospitals commonly provide a short-term supply of free P2Y₁₂ inhibitors at discharge after myocardial infarction, but it is unclear if these programs improve medication persistence and outcomes. The ARTEMIS (Affordability and Real-World Antiplatelet Treatment Effectiveness After Myocardial Infarction Study) trial randomized hospitals to usual care versus waived P2Y₁₂ inhibitor copayment costs for 1-year post-myocardial infarction. Whether the impact of this intervention differed between hospitals with and without pre-existing medication assistance programs is unknown. Methods and Results In this post hoc analysis of the ARTEMIS trial, we examined the associations of pre-study free medication programs and the randomized copayment voucher intervention with P2Y₁₂ inhibitor persistence (measured by pharmacy fills and patient report) and major adverse cardiovascular events using logistic regression models including a propensity score. Among 262 hospitals, 129 (49%) offered pre-study free medication assistance. One-year P2Y₁₂ inhibitor persistence and major adverse cardiovascular events risks were similar between patients treated at hospitals with and without free medication programs (adjusted odds ratio 0.93, 95% CI, 0.82-1.05 and hazard ratio 0.92, 95% CI, 0.80-1.07, respectively). The randomized copayment voucher intervention improved persistence, assessed by pharmacy fills, in both hospitals with (53.6% versus 44.0%, adjusted odds ratio 1.45, 95% CI, 1.20-1.75) and without (59.0% versus 48.3%, adjusted odds ratio 1.46, 95% CI, 1.25-1.70) free medication programs (P_interaction=0.71). Differences in patient-reported persistence were not significant after adjustment. Conclusions While hospitals commonly report the ability to provide free short-term P2Y₁₂ inhibitors, we did not find association of this with medication persistence or major adverse cardiovascular events among patients with insurance coverage for prescription medication enrolled in the ARTEMIS trial. An intervention that provided copayment assistance vouchers for 1 year was successful in improving medication persistence in hospitals with and without pre-existing short-term medication programs. Registration URL: https://www.clini​caltr​ials.gov/. Unique identifier: NCT02406677.