Randomized Assessment of Ticagrelor Versus Prasugrel Antiplatelet Effects in Patients With Diabetes

OBJECTIVE: It has been postulated that prasugrel might be the preferred treatment option in diabetes mellitus (DM) patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). We aimed to compare the pharmacodynamic action of ticagrelor versus prasugrel. RESEARCH DESIGN AND METHODS: In a prospective, single-center, single-blind, crossover study, 30 consecutive ACS patients with DM who had been pretreated with clopidogrel were randomized to either 90 mg ticagrelor twice daily or 10 mg prasugrel once daily with a 15-day treatment period. Platelet reactivity (PR) was assessed with the VerifyNow P2Y12 function assay, measured in P2Y12 reaction units (PRU). RESULTS: PR was significantly lower after ticagrelor (45.2 PRU [95% CI 27.4–63.1]) compared with prasugrel (80.8 PRU [63.0–98.7]), with a least squares mean difference of –35.6 PRU (−55.2 to −15.9, P = 0.001). High PR rate was 0% for ticagrelor and 3.3% for prasugrel (P = 1.0). CONCLUSIONS: In DM patients with ACS who had been pretreated with clopidogrel and who undergo PCI, ticagrelor achieves a significantly higher platelet inhibition than prasugrel. Both antiplatelet agents effectively treat high PR. The relevance of these findings to the clinical efficacy and safety of ticagrelor and prasugrel in DM patients needs further elucidation.