This study aims to describe temporal trends in the use and costs of clopidogrel, ticagrelor, and prasugrel in Germany and the United States.

Oral P2Y12 inhibitors are a cornerstone of secondary prevention after acute myocardial infarction. In randomized trials, the potent P2Y12 inhibitors ticagrelor and prasugrel reduced ischemic events compared with clopidogrel. More recently, head-to-head comparisons between ticagrelor and prasugrel confirmed prasugrel's noninferiority and/or superiority compared with ticagrelor. The extent to which this evolving evidence has been incorporated into practice across healthcare systems remains unclear. Therefore, this study aims to describe temporal trends in P2Y12 inhibitor use and associated treatment costs in Germany and the United States (US) from 2011 through 2024.

The database study will use a new-user design to evaluate age- and sex-standardized use of clopidogrel, ticagrelor, and prasugrel initiators among P2Y12 inhibitor initiators over time in separate German and US populations following evolving clinical evidence and guideline recommendations. The 12-month treatment costs for each treatment will be assessed over time. In addition, population-level temporal trends in major adverse cardiovascular events and bleeding-related hospitalizations will be described in Germany in the context of changes in clinical treatment guidelines for P2Y12 inhibitor selection after acute myocardial infarction. In the US, industry payments related to ticagrelor and prasugrel made to healthcare providers will be analyzed. Provider-level prescribing patterns according to receipt of industry payments will be described.

This study uses a series of descriptive observational analyses conducted using German and US healthcare claims data, the CMS Open Payments database, and Medicare Part D prescribing data by national provider identifier.

Patient-level analyses will use new-user cohort study designs conducted separately in German and US administrative healthcare claims databases. These analyses will evaluate temporal trends in the age- and sex-standardized initiation of clopidogrel, ticagrelor, and prasugrel among adults initiating outpatient P2Y12 inhibitor therapy after acute myocardial infarction and describe these trends in the context of the evolving evidence base and guideline recommendations. In addition, patient-level analyses will assess temporal trends in 12-month treatment costs, as well as population-level trends in major adverse cardiovascular events and bleeding-related hospitalizations among P2Y12 inhibitor initiators in Germany.

Separate US-based analyses will evaluate industry payments associated with ticagrelor and prasugrel reported in the CMS Open Payments database and provider-level prescribing patterns according to receipt of ticagrelor-associated industry payments using linked Medicare Part D prescribing data.

Eligible cohort entry dates for patient-level analyses will range from 2011 through 2024.

PATIENT-LEVEL COHORT ANALYSES

Inclusion Criteria

• Adults aged ≥18 years
• Acute myocardial infarction
• Initiation of outpatient treatment with clopidogrel, ticagrelor, or prasugrel

Exclusion Criteria

• Prior use of clopidogrel, ticagrelor, or prasugrel
• Initiation of more than one study drug on the cohort entry date
• Missing age or sex information
• Insufficient baseline claims enrollment

TICAGRELOR-TO-PRASUGREL COST-SAVING ANALYSIS IN THE UNITED STATES

Eligibility Criteria

• Adults aged ≥18 years
• Acute myocardial infarction
• Initiation of outpatient treatment with ticagrelor

INDUSTRY PAYMENT ANALYSIS IN THE UNITED STATES

Eligibility Criteria

• General and research payment records in the CMS Open Payments database
• Ticagrelor or prasugrel listed as the associated drug

PROVIDER-LEVEL PRESCRIBING ANALYSIS

Eligibility Criteria

• US Medicare Part D providers
• >10 ticagrelor or prasugrel claims during both the baseline period (2020-2021) and outcome period (2022-2023).

Adults aged ≥18 years with acute myocardial infarction who initiated outpatient treatment with clopidogrel, ticagrelor, or prasugrel.