OBJECTIVES: Hemophilia B (HB) is a bleeding disorder characterized by deficiency or complete lack of coagulation factor IX (FIX). Moderate-to-severe HB is treated with lifelong, continuous FIX replacement therapy to prevent bleeding. In Finland, four different FIX replacement products are available, i.e., human coagulation factor IX, nonacog alfa, eftrenonacog alfa, and nonacog beta pegol. This real-world evidence study aims to provide up-to-date information on HB patient numbers, treatment modalities and FIX costs in Finland.

METHODS: Data from the Social Insurance Institution of Finland (SII) were used to assess the number of HB patients based on FIX product purchases (ATC B02BD04) and to reveal the corresponding FIX treatment costs during 2019-2022 stratified by age groups. Treatment modality (prophylaxis, PPX and on-demand, OD) was assessed based on the number of annual FIX purchases per patient.

RESULTS: In total, n=50 (2019), n=47 (2020), n=42 (2021), and n=44 (2022) unique HB patients purchased FIX products. Patients were distributed across a wide range of age groups, with the highest number of patients aged 18-44. No patients were 0-5 years or over 85 (2022). All patients were males. Overall annual FIX treatment costs for all patients independent of age group and treatment modality were 6,4m€, 6,3m€, 6,2m€, and 5,9m€ for years 2019, 2020, 2021, and 2022 respectively. In 2022, the mean annual FIX treatment cost per patient <18 years of age was 114,173€ (n= 3, PPX; no patients with evident OD treatment); 18-65 years 230,150€ (n= 8, PPX) and 104,611€ (n= 14, OD); and >65 years 215,569€ (n= 2, PPX) and 92,452€ (n= 3, OD). Mean annual FIX costs for adult patients with uncertain treatment modality were 131,672€ (n=12).

CONCLUSIONS: FIX product costs are the main driver for the high economic burden for HB treatment. Annual FIX treatment costs varied depending on age group and treatment regimen.