Platelet Inhibition with Ticagrelor 60 mg Versus 90 mg Twice Daily in Elderly Patients with Acute Coronary Syndrome: Rationale and Design of the PLINY THE ELDER Trial.

BACKGROUND: Elderly status is steadily increasing among patients with acute coronary syndrome (ACS). Dual antiplatelet therapy (DAPT) with aspirin and a potent P2Y12 receptor inhibitor is the cornerstone of treatment to prevent recurrent thrombotic complications in patients with ACS. However, DAPT in older patients is challenged by a concurrent heightened risk of ischemia and bleeding. The aim of this study is to evaluate the pharmacodynamic and pharmacokinetic profile of a lower dose of ticagrelor (60 mg twice daily) among elderly patients during the early phase of ACS. STUDY DESIGN: PLINY THE ELDER (PLatelet INhibition with two different doses of potent P2y12 inhibitors in THE ELDERly population) (NCT04739384) is a prospective, randomized, open-label, crossover trial to evaluate the non-inferiority of a lower dose of ticagrelor (60 mg twice daily) compared with a standard dose (90 mg twice daily) among elderly patients with ACS undergoing percutaneous coronary intervention (PCI). A total of 50 patients, aged 75 years or more, with indication to potent P2Y12 receptor inhibitors will be randomized within 3 days from PCI for the index ACS. Patients with indication to oral anticoagulant therapy, treatment with glycoprotein IIb/IIIa inhibitors, or active bleeding will be excluded. The primary endpoint is platelet reactivity determined by P2Y12 reaction units (PRU) (VerifyNow, Accumetrics, San Diego, CA, USA) after treatment with ticagrelor 60 or 90 mg twice daily for 14 days. Secondary endpoints will include other pharmacodynamic tests of ADP-induced aggregation (light transmittance aggregometry and multiple electrode aggregometry) and determination of pharmacokinetic profile (plasma levels of ticagrelor and its metabolite AR-C124910XX) by high performance liquid chromatography-tandem mass spectrometry. CONCLUSIONS: The PLINY THE ELDER trial will determine whether a lower dose of ticagrelor confers non-inferior platelet inhibition compared with the standard dose in the early phase of ACS among elderly patients undergoing PCI, informing future clinical investigation.