Abstract P274: Cross-sectional Analysis of Baseline Characteristics for New Users of Vorapaxar (PAR-1 Antagonist) and P2Y 12 Inhibitors

Abstract

Introduction: Vorapaxar is indicated for the reduction of thrombotic events in patients with a prior myocardial infarction (MI) or peripheral arterial disease (PAD), and contraindicated in patients with a prior stroke, transient ischemic attack (TIA), or intracranial hemorrhage (ICH). This is the first descriptive study of vorapaxar in US clinical practice. Objectives: Main objective was to describe baseline characteristics of vorapaxar new users. For context, P2Y 12 new users were also examined, with indications summarized in Table 1. Methods: Cross-sectional analysis of vorapaxar new users ≥18 years with ≥1 prescription between June 2014 - June 2016 identified in Symphony Health’s outpatient pharmacy claims database linked to private practitioner claims and hospital data. Concomitant clopidogrel use was defined with overlapping days of supply. Medical history was defined using a 1-year baseline period. Results: The analysis included 1,362 vorapaxar (44% with clopidogrel), 975,023 clopidogrel, 133,724 ticagrelor, and 98,101 prasugrel new users (Table 1). Most ticagrelor (87%) and prasugrel (85%) users had evidence of coronary artery disease (CAD) compared with 52% of clopidogrel and 58% of vorapaxar users. In contrast, <1% of ticagrelor and prasugrel users had PAD but no CAD vs. 6% of clopidogrel and 15% of vorapaxar users. The proportion of vorapaxar users (44%) with PAD, alone or with CAD, was 3-5 times larger than P2Y 12 users. PAD was more prevalent for vorapaxar with (50%) vs. without (39%) clopidogrel. Contraindications were infrequent for vorapaxar users - no ICH, <4% with stroke or TIA. Median time from recent MI to therapy start was 6 months for vorapaxar vs. 3 days for ticagrelor and prasugrel and 7 days for clopidogrel. Vorapaxar users were mostly male and on average ~65 years old. Conclusions: The majority of vorapaxar new users had a history of CAD and/or PAD, with PAD prevalence more than twice that of P2Y 12 new users. Contraindications were infrequent.