Safety, tolerability, pharmacokinetics and pharmacodynamics of milvexian with aspirin and/or clopidogrel in healthy participants

Milvexian, an oral activated Factor XI (FXIa) inhibitor, is in clinical studies where it may be combined with antiplatelet agents, including aspirin and/or clopidogrel, to prevent thromboembolic diseases. This phase I trial assessed safety, pharmacokinetics, and pharmacodynamics of milvexian coadministration with aspirin and/or clopidogrel in healthy participants through 3 drug-drug interaction studies using a 3-period, 3-treatment, crossover design. A total of 113 participants were randomized to receive milvexian (200 mg; twice daily for 5 days) or matched placebo coadministered with once-daily aspirin (325 mg for 5 days) and/or clopidogrel (Day 1: 300 mg; Days 2–5: 75 mg). Milvexian was safe and well tolerated, with and without aspirin and/or clopidogrel. Eight mild bleeding adverse events (AEs) were reported in 5 of 113 participants across various treatment arms. Peak and total exposures of milvexian were similar with or without clopidogrel and/or aspirin. Exposure-dependent prolongation of activated partial thromboplastin time and reduction of FXI clotting activity by milvexian were similar with coadministration of aspirin and/or clopidogrel. Milvexian, with or without coadministration of aspirin and/or clopidogrel, did not affect bleeding time or platelet aggregation. Administration of milvexian alone or with aspirin and/or clopidogrel was safe and well tolerated without increased incidence of AEs, including bleeding. Pharmacokinetic and pharmacodynamic effects of milvexian, including bleeding time, were similar with or without aspirin and/or clopidogrel. ClinicalTrials.gov Identifier : NCT03698513.