PB0490 - Real-world outcomes of prophylaxis with extended half-life factor IX products for hemophilia B: a pooled analysis of medical chart data from Germany and Italy

Monday, June 24, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Co-Author(s)

Johannes Oldenburg, MD

Professor, Chairman and Director
University Clinic Bonn AöR, Institute of Experimental Haematology and Transfusion Medicine
Bonn, Nordrhein-Westfalen, Germany
Mariasanta Napolitano

MD
PROMISE Department, University of Palermo, Palermo, Italy
Palermo, Sicilia, Italy

Presenting Author(s)

SY

Songkai Yan

Director, Global Evidence, Market Access and Pricing
CSL Behring, King of Prussia, PA, USA
King of Prussia, Pennsylvania, United States

Co-Author(s)

YY

Ying Yang

Senior consultant
Adivo Associates LLC, CA, USA
San Francisco, California, United States
RT

Radovan Tomic

Director Market Access Europe
CSL Behring, Milan, Italy
Milan, Lombardia, Italy
XZ

Xiang Zhang

Director, Medical Affairs Biostatistics Quantitative Clinical Sciences and Reporting
CSL Behring, King of Prussia, PA, USA
King of Prussia, Pennsylvania, United States
DD

Douglass Drelich

Assoc Director, Global Medical Affairs Hematology
CSL Behring, King of Prussia, PA, USA
King of Prussia, Pennsylvania, United States
NJ

Natalie Jakobs

Healthcare Consultant
Adivo Associates LLC, CA, USA
San Francisco, California, United States
Martin Olivieri

Head of Pediatric Thrombosis and Hemostasis Unit, Pediatric Hemophilia Center
Paediatric Thrombosis and Haemostasis Unit, Dr. von Hauner Children's Hospital LMU Munich, Germany
munich, Bayern, Germany

Background: European Medicines Agency approved rIX-FP, rFIXFc and N9-GP for treating people with hemophilia B (PwHB). Clinical trials demonstrated the efficacy and safety of each product; however, real-world data are needed to understand the outcomes of prophylaxis in the absence of direct head-to-head trials.

Aims: To assess real-world FIX consumption and bleeding outcomes for PwHB with severe or moderate hemophilia B aged ≥12 years receiving rIX-FP, rFIXFc or N9-GP prophylaxis.

Methods: De-identified medical chart information were obtained from German and Italian hemophilia treatment centers between 2020–2023. PwHB treated prophylactically for ≥12 months were included (Germany [rIX-FP, rFIXFc or N9-GP] and Italy [rIX-FP or rFIXFc]). FIX consumption was calculated using most recent prescribed dosing frequency and dosage. Annualized bleeding rate (ABR), annualized spontaneous bleeding rate (AsBR) and annualized joint bleeding rate (AjBR) were calculated by annualizing number of bleeding events over the observation period. Generalized linear models adjusting for covariates were used to test statistical differences of consumption and ABR between the products.

Results: Overall, 225 PwHB were included (mean age 34.1 years; 66% with severe hemophilia B; Table 1). Pooled results for consumption and bleeding rates are presented in Table 2. PwHB treated with rIX-FP prophylaxis had significantly lower FIX consumption compared to those treated with rFIXFc: mean 42.4 IU/kg/week vs. 65.2 IU/kg/week (p=0.0001); difference between rIX-FP and N9-GP (47.2 IU/kg/week, p=0.9174) was not significant. Bleed rates were generally low. ABR (mean) was not significantly different for rIX-FP prophylaxis (0.7) vs. rFIXFc (1.1; p=0.6704) and vs. N9-GP (1.5; p=0.0769). Mean AsBR for rIX-FP prophylaxis vs. rFIXFc and N9-GP were 0.1, 0.3 and 0.6, respectively. Mean AjBR were 0.3, 0.4 and 0.6, respectively.

Conclusion(s): Results suggest that rIX-FP prophylaxis was associated with lower FIX consumption compared with rFIXFc and N9-GP treatments, and provided similar or potentially improved bleed protection.