Abbreviated or Standard Antiplatelet Therapy in HBR Patients: Final 15-Month Results of the MASTER-DAPT Trial

BACKGROUND Clinical outcomes and treatment selection after completing the randomized phase of modern trials, investigating antiplatelet therapy (APT) after percutaneous coronary intervention (PCI), are unknown. OBJECTIVES The authors sought to investigate cumulative 15-month and 12-to-15-month outcomes after PCI during routine care in the MASTER DAPT trial. METHODS The MASTER DAPT trial randomized 4,579 high bleeding risk patients to abbreviated (n = 2,295) or standard (n = 2,284) APT regimens. Coprimary outcomes were net adverse clinical outcomes (NACE) (all-cause death, myocardial infarction, stroke, and BARC 3 or 5 bleeding); major adverse cardiac and cerebral events (MACCE) (all-cause death, myocardial infarction, and stroke); and BARC type 2, 3, or 5 bleeding. RESULTS At 15 months, prior allocation to a standard APT regimen was associated with greater use of intensified APT; NACE and MACCE did not differ between abbreviated vs standard APT (HR: 0.92 [95% CI: 0.76-1.12]; P = 0.399 and HR: 0.94 [95% CI: 0.76-1.17]; P = 0.579; respectively), as during the routine care period (HR: 0.81 [95% CI: 0.50-1.30]; P = 0.387 and HR: 0.74 [95% CI: 0.43-1.26]; P = 0.268; respectively). BARC 2, 3, or 5 was lower with abbreviated APT at 15 months (HR: 0.68 [95% CI: 0.56-0.83]; P = 0.0001) and did not differ during the routine care period. The treatment effects during routine care were consistent with those observed within 12 months after PCI. CONCLUSIONS At 15 months, NACE and MACCE did not differ in the 2 study groups, whereas the risk of major or clinically relevant nonmajor bleeding remained lower with abbreviated compared with standard APT. (Management of High Bleeding Risk Patients Post Bioresorbable Polymer Coated Stent Implantation With an Abbreviated Versus Prolonged DAPT Regimen [MASTER DAPT]; NCT03023020) (J Am Coll Cardiol Intv 2023;16:798-812) (c) 2023 by the American College of Cardiology Foundation.