#408-12 ACC 2024 - October 2025

Novel Anticoagulant Shows Superior Outcomes in Atrial Fibrillation

Dr. Robert Williams, Dr. Lisa Anderson, Dr. James Martinez, Dr. Patricia Taylor
Therapeutic Area: Cardiology
Company: Merck
Study Type: Randomized Controlled Trial

Key Findings

Drug Y reduced the risk of stroke or systemic embolism by 35% compared to warfarin (p<0.001). Major bleeding events were reduced by 28%. Intracranial hemorrhage was significantly lower in Drug Y group (0.3% vs 0.8% per year).

Summary

New anticoagulant demonstrates reduced stroke risk and fewer bleeding events compared to warfarin in AF patients.

Study Design

Randomized, double-blind, double-dummy trial comparing Drug Y 150mg twice daily with dose-adjusted warfarin (target INR 2.0-3.0) in 18,000 patients with non-valvular atrial fibrillation and at least one additional stroke risk factor.

Methods

Patients were followed for median of 2.5 years. Primary efficacy outcome was stroke or systemic embolism. Primary safety outcome was major bleeding according to International Society on Thrombosis and Haemostasis criteria. Pre-specified subgroup analyses examined outcomes by age, renal function, and prior stroke.

Results

Annual rate of stroke/systemic embolism: 1.1% with Drug Y versus 1.7% with warfarin (HR=0.65, 95% CI: 0.52-0.81, p<0.001). Annual rate of major bleeding: 2.7% versus 3.6% (HR=0.72, 95% CI: 0.63-0.84, p<0.001). Benefits were consistent across all pre-specified subgroups.

Conclusions

Drug Y provides superior stroke prevention with improved safety compared to warfarin in patients with atrial fibrillation. The consistent benefits across diverse patient populations support broad clinical applicability. Fixed dosing without need for routine monitoring offers practical advantages.

Full Abstract

This international, multicenter, randomized controlled trial compared Drug Y, a novel oral anticoagulant, with warfarin in patients with non-valvular atrial fibrillation at risk for stroke.