Hemostatic Efficacy and Safety of Weight-Based Versus Fixed-Dose 4F-PCC for Vitamin K Antagonist Reversal.

Four-factor prothrombin complex concentrate (4F-PCC) is indicated for vitamin K antagonist (VKA) reversal but is associated with thrombotic events (TE). In 2018, the institution revised 4F-PCC dosing for VKA reversal from INR and weight-based dosing to a fixed-dose of 1500 units. The purpose of this study was to compare hemostatic efficacy and TE rate of fixed-dose 4PCC to weight-based dosing. This was a retrospective, single-center, quasi-experimental study of adult patients who received 4F-PCC for VKA reversal from January 2014 through May 2016 (INR and weight-based dosing) or April through October 2018 (fixed-dosing). The primary endpoint was hemostatic efficacy, defined by achieving an INR of ≤1.4, or an INR of ≤1.7 with evidence of hemostasis. The key secondary endpoint was TE within 14 days of 4F-PCC administration. Data were analyzed using descriptive statistics, chi-squared for nominal data and Mann-Whitney U for ordinal and continuous data. The study included 163 patients who received weight-based dosing and 45 who received fixed-dose 4F-PCC. Hemostatic efficacy was 76.9% of patients in the weight-based group and 77.4% of patients in the fixed-dose group ( = .229). TE occurred in 13.5% of the weight-based vs 6.7% of the fixed-dose group ( = .181). This study found no difference in hemostatic efficacy with fixed-dose 4F-PCC for VKA reversal compared to INR and weight-based dosing. The occurrence of TE was reduced by 50% with the 4F-PCC fixed-dose strategy; however, this difference was not statistically significant. Further randomized studies are needed to confirm these results.