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

• Published in: European journal of haematology Vol. 112; no. 5; pp. 765 - 775
• Main Authors: Giordano, Paola, Pollio, Berardino, Sottilotta, Gianluca, Biasoli, Chiara, Daniele, Filomena, De Cristofaro, Raimondo, Peyvandi, Flora, Villa, Maria Rosaria, Castaman, Giancarlo
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.05.2024
• Subjects: Bleeding; Clinical outcomes; Disease prevention; Factor IX deficiency; Hemophilia; Patients; Pediatrics; Prophylaxis; haemophilia B; observational; bleeding; rIX‐FP; real‐world; nonacog‐alfa; prophylaxis; pediatric
• ISSN: 0902-4441; 1600-0609; 1600-0609
• DOI: 10.1111/ejh.14168

To evaluate pattern of use and clinical outcomes in pediatric/adolescent patients enrolled in the IDEAL study. This post-hoc analysis of IDEAL retrospective-prospective observational study focused on patients <18 years, 100% on prophylaxis during the entire observation period. Thirteen 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. The 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.