Pattern of use and clinical outcomes with rIX‐FP in pediatric/adolescent patients with haemophilia B in Italy: Results from IDEAL real‐world study

Abstract

AbstractObjectivesTo evaluate pattern of use and clinical outcomes in pediatric/adolescent patients enrolled in the IDEAL study.MethodsThis post‐hoc analysis of IDEAL retrospective‐prospective observational study focused on patients <18 years, 100% on prophylaxis during the entire observation period.ResultsThirteen subjects (median age 10.0 years; 61.5% ≤ 11 years) were analyzed. The infusion frequency changed from 2/week in 84.6% (N = 11) of patients with previous rFIX, to less than 1/weekly in 76.9% (N = 9) with rIX‐FP and the annualized number of infusions reduced of 57% (p = .002), from a mean ± SD of 95.1 ± 22.77 to 40.4 ± 6.79, respectively. Annualized mean consumption decreased of about 56% (p = .001), from 3748.4 ± 1155.40 IU/kg with previous rFIX, to 1656.8 ± 456.63 IU/kg of rIX‐FP. Mean FIX trough level changed from 3.0% ± 1.98% to 10.92% ± 3.6%. Low mean Annualized Bleeding Rate was maintained across all prophylaxis regimens (0.8 ± 1.69 vs. 0.3 ± 0.89) and zero bleeding patients moved from 69.2% (N = 9) with previous rFIX to 84.6% (N = 11) with rIX‐FP (p = .63). Two adverse events, none related to rIX‐FP, occurred in two patients. No inhibitors development was reported.ConclusionsThe results in this pediatric/adolescent subgroup support rIX‐FP prophylaxis may reduce infusion frequency, while providing high FIX trough levels, stable annualized bleeding rate and a good safety profile.