Search

Background: Oral activated factor XI (FXIa) inhibitors may modulate coagulation to prevent thromboembolic events without substantially increasing bleeding. We explored the pharmacodynamics, safety, and efficacy of the oral FXIa inhibitor asundexian for secondary prevention after acute myocardial infarction (MI). Methods: We randomized 1601 patients with recent acute MI to oral asundexian 10, 20, or 50 mg or placebo once daily for 6 to 12 months in a double-blind, placebo-controlled, phase 2, dose-ranging trial. Patients were randomized within 5 days of their qualifying MI and received dual antiplatelet therapy with aspirin plus a P2Y12 inhibitor. The effect of asundexian on FXIa inhibition was assessed at 4 weeks. The prespecified main safety outcome was Bleeding Academic Research Consortium type 2, 3, or 5 bleeding comparing all pooled asundexian doses with placebo. The prespecified efficacy outcome was a composite of cardiovascular death, MI, stroke, or stent thrombosis comparing pooled asundexian 20 and 50 mg doses with placebo. Results: The median age was 68 years, 23% of participants were women, 51% had ST-segment–elevation MI, 80% were treated with aspirin plus ticagrelor or prasugrel, and 99% underwent percutaneous coronary intervention before randomization. Asundexian caused dose-related inhibition of FXIa activity, with 50 mg resulting in >90% inhibition. Over a median follow-up of 368 days, the main safety outcome occurred in 30 (7.6%), 32 (8.1%), 42 (10.5%), and 36 (9.0%) patients receiving asundexian 10 mg, 20 mg, or 50 mg, or placebo, respectively (pooled asundexian versus placebo: hazard ratio, 0.98 [90% CI, 0.71–1.35]). The efficacy outcome occurred in 27 (6.8%), 24 (6.0%), 22 (5.5%), and 22 (5.5%) patients assigned asundexian 10 mg, 20 mg, or 50 mg, or placebo, respectively (pooled asundexian 20 and 50 mg versus placebo: hazard ratio, 1.05 [90% CI, 0.69–1.61]). Conclusions: In patients with recent acute MI, 3 doses of asundexian, when added to aspirin plus a P2Y12 inhibitor, resulted in dose-dependent, near-complete inhibition of FXIa activity without a significant increase in bleeding and a low rate of ischemic events. These data support the investigation of asundexian at a dose of 50 mg daily in an adequately powered clinical trial of patients who experienced acute MI. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04304534; URL: https://www.clinicaltrialsregister.eu/ctr-search/search ; Unique identifier: 2019-003244-79.

Introduction Patients with atrial fibrillation (AF) after percutaneous coronary intervention (PCI) receive clopidogrel and direct oral anticoagulation. Platelet inhibition by clopidogrel varies according to CYP2C19 genotype. This study aimed to investigate the association of CYP2C19 genotype with antiplatelet effect of clopidogrel and ischemic and bleeding risk. Methods In this prospective observational study, patients with AF after PCI were grouped according to CYP2C19*2 and *17 diplotypes: *2/non-17* or *2/*2 as reduced metabolizers (RM), non-*2/*17 or *17/*17 as increased metabolizers (IM), and the remaining as normal metabolizers (NM). Platelet aggregation [U] was quantified by multiple electrode aggregometry. The primary outcome was time to death, myocardial infarction, or stroke (MACE) at 6 months. The secondary outcome was time to non-major clinically relevant (NMCR) or major bleedings. Results 156 patients were enrolled between May 2020 and May 2021. The median age was 78 years (interquartile range, IQR 71–82) and 109 (70%) were male. 31 patients (20%) were RM, 74 patients (47%) NM and 51 patients (33%) IM. The median ADP-induced platelet aggregation was not significantly different across these groups (RM: 12.8 [U]; NM: vs. 12.8 [U]; IM: 11.7 [U]; P = 0.39).The primary outcome occurred in 11 (7%) patients (RM: 1 [3%]; NM: 7 [9%]; IM 3[6%]). The secondary outcome occured in 3 RM (10%) and in 20 (16%) with NM + IM subtypes (HR 0.65 [95% CI 0.19–2.18], P = 0.485). Conclusion In this analysis reduced metabolizers were not at excessively increased risk of MACE. A trend for less bleeding was observed in carriers of loss-of-function allele CYP2C19*2.

Background: High on-clopidogrel platelet reactivity (HPR) following percutaneous coronary intervention (PCI) is associated with increased ischemic risk. It is unclear whether conventional definitions of HPR apply to patients with concomitant oral anticoagulation (OAC). This study aimed to compare the performance of multiple platelet aggregometry (MEA) and thrombelastography (TEG) to detect HPR in patients with atrial fibrillation (AF) and indication for an OAC. Methods: In this observational single-center cohort study, MEA and TEG were performed in patients with AF with an indication for OAC on day 1 to 3 after PCI. The primary outcome was HPR as assessed by MEA (ADP area under the curve ≥ 46 units [U]) or TEG (MAADP ≥ 47 mm), respectively. The secondary exploratory outcomes were a composite of all-cause death, myocardial infarction (MI) or stroke and bleeding, as defined by the International Society on Thrombosis and Hemostasis, at 6 months. Results: Platelet function of 39 patients was analyzed. The median age was 78 (interquartile range [IQR] was 72–82) years. 25 (64%) patients were male, and 19 (49%) presented with acute coronary syndrome. All patients received acetylsalicylic acid and clopidogrel prior to PCI. Median (IQR) ADP-induced aggregation, MAADP, TRAP-induced aggregation, and MAthrombin were 9 (6–15) U, 50 (43–60) mm, 54 (35–77) U and 65 (60–67) mm, respectively. The rate of HPR was significantly higher if assessed by TEG compared with MEA (25 [64%] vs. 1 [3%]; p < 0.001). Within 6 months, four (10%) deaths, one (3%) MI and nine (23%) bleeding events occurred. Conclusion: In patients with AF undergoing PCI, the rates of HPR detected by TEG were significantly higher compared with MEA. Conventional cut-off values for HPR as proposed by consensus documents may need to be re-evaluated for this population at high ischemic and bleeding risk. Further studies are needed to assess the association with outcomes.