Validation of a Scoring System for Prediction of Clinical Outcome in the Offlabel Use of Recombinant Factor VIIa

Abstract

Background and Objectives: Recombinant factor VIIa (rFVIIa) is approved for treatment of inhibitors in hemophilia but has also been used for numerous off-label indications. Type of study: This study aims to validate a modified Biss scoring system in patients who received recombinant factor rFVIIa in Jeddah, Saudi Arabia. Materials and Methods: We included 70 patients who received rFVIIa for off-label indications over 12 months. Characteristics of survivor and non-survivor groups were compared including demographics, laboratory and clinical data. Using a modified Biss prognostic scoring system, based on the original scoring system used by Biss and Hanley, patients were divided into low (<1), intermediate (1-2) and high (≥3) score groups. Results: The mean age of patients was 46.1(±18.6) years. The most common off-label indications for rFVIIa treatment were to control bleeding associated with cardiac surgery (33%) and management of intracranial hemorrhage (18.8%). Forty three patients (61.6%) were at low risk, 20(28.6%) were at intermediate risk, and 7 (10%) were at high risk. Survivors were younger than non-survivors and less likely to have coagulopathy, or renal impairment at the time of treatment. The total prognostic score correlated to survival outcome (P ≤ 0.042); 73.2%, 22%, 4.9% of survivors had a low, intermediate and high score, respectively. Conclusions: Our results suggest that a modified Biss score could help predict survival of patients receiving rFVIIa. Prospective studies are needed to further validate the utility of this scoring system.