Comparing Real-World Outcomes of Prophylaxis with Extended Half-life Factor IX (rIX-FP vs. rFIXFc and N9-GP) for Haemophilia B: An Analysis of Medical Chart Data from Germany.

INTRODUCTION

In Germany, three extended half-life factor IX (FIX) products are commonly used to treat people with haemophilia B (PwHB). However, there remains a critical need to differentiate treatments for PwHB. The aim of this study was to assess the effectiveness and utilisation of rIX-FP compared with rFIXFc and N9-GP for prophylaxis in clinical practice in Germany.

METHODS

A retrospective chart review was performed for PwHB aged ≥ 12 years with moderate/severe haemophilia B, who received prophylaxis with rIX-FP, rFIXFc or N9-GP for ≥ 12 months. The primary outcome was FIX consumption; secondary outcomes included annualised bleeding rate (ABR), annualised spontaneous bleeding rate (AsBR) and annualised joint bleeding rate (AjBR).

RESULTS

The study included 138 PwHB: rIX-FP, n = 52; rFIXFc, n = 55; and N9-GP, n = 31. Mean FIX consumption with rIX-FP (46.9 IU/kg/week) was significantly lower than that of rFIXFc (70.1 IU/kg/week, p = 0.0083) but not significantly different from N9-GP (47.2 IU/kg/week, p = 0.9331). PwHB receiving rIX-FP prophylaxis had significantly lower mean bleeding rates than those receiving N9-GP (ABR: 0.8 vs. 1.5, p = 0.0472; AsBR: 0.1 vs. 0.6, p = 0.0092; and AjBR: 0.2 vs. 0.6, p = 0.0140). Bleeding rates for rIX-FP and rFIXFc did not differ significantly.

CONCLUSION

rIX-FP prophylaxis was associated with significantly lower FIX consumption and numerically (but not significantly) lower bleeding rates compared with rFIXFc. Compared to N9-GP, prophylaxis with rIX-FP was associated with similar FIX consumption and significantly lower bleeding rates.