Efficacy and safety of a 4-factor prothrombin complex concentrate for rapid vitamin K antagonist reversal in Japanese patients presenting with major bleeding or requiring urgent surgical or invasive procedures: a prospective, open-label, single-arm phase 3b study.

Rapid vitamin K antagonist (VKA) reversal is required in patients experiencing major bleeding or requiring urgent surgery. Four-factor prothrombin complex concentrate (4F-PCC; Beriplex®/Kcentra®) was shown in two large randomized controlled, international phase 3b trials to be an effective alternative to plasma for urgent VKA reversal. In the present prospective, open-label, single-arm phase 3b trial, we evaluate the efficacy and safety of 4F-PCC in Japanese patients. Eleven patients [international normalized ratio (INR) ≥2] requiring rapid VKA reversal owing to major bleeding (n = 6) or before urgent surgical/invasive procedures (n = 5) were administered 4F-PCC dosed based on INR and weight. INR reduction (≤1.3 0.5 h postinfusion; primary endpoint) was achieved in 81.8% of patients (major bleeding, 83.3%; surgical/invasive procedures, 80.0%). Effective hemostasis (main secondary endpoint) was met in 60.0% (major bleeding) and 100% (surgical/invasive procedure) of evaluable patients. Adverse events (AEs) and serious AEs were reported in 90.9 and 45.5% of patients, respectively. Two AEs were considered treatment-related; thromboembolic events rated mild and not clinically relevant by investigators. There were no deaths, fluid overload events, or viral transmission cases. Consistent with the previous results, 4F-PCC may be an effective and well-tolerated treatment for rapid VKA reversal in Japanese patients experiencing major bleeding or requiring urgent surgical/invasive procedures.