ABSTRACT
BACKGROUND: Following induced joint hemorrhage, hemophilia B results in the abnormal persistence of iron deposition, inflammation, and neovascularity of the synovial tissue, as well as deterioration of the bone articular surface and strength. Previously, we demonstrated that a factor IX (FIX) replacement protein with extended circulating FIX activity, glycoPEGylated FIX nonacog beta pegol (N9-GP), could improve synovial and osteochondral parameters in F9 knockout mice when administered after joint injury. OBJECTIVE: We explored the use of N9-GP prior to unilateral joint hemorrhage and compared to unmodified recombinant FIX (rFIX). METHODS: Pharmacodynamics, histology, and microcomputed tomography were used to assess the effects of prophylactic administration of glycoPEGylated FIX. RESULTS: In comparison to rFIX, N9-GP significantly improved soft tissue histological parameters, as well as bone outcome at 2 weeks post injury, while performing equally in reduction of blood present in the joint space assessed 1 day after injury. CONCLUSIONS: These results indicate that, in comparison to rFIX, the prophylactic use of extended half-life FIX provides superior protection from bleeding-induced joint damage, manifested by improved correction of histologic parameters.
