Long-term FEIBA prophylaxis does not prevent progression of existing joint disease

Area of Science:

• Hematology
• Pharmacology

Background:

• Activated prothrombin complex concentrates, including FEIBA (FVIII bypassing activity), have been used for bleeding episodes in patients with Factor VIII inhibitors.
• FEIBA has also been utilized in FVIII immune tolerance programs.
• Limited data exists on the long-term safety and efficacy of FEIBA prophylaxis for preventing hemophilic arthropathy.

Purpose of the Study:

• To evaluate the outcome of hemophilic arthropathy in patients receiving long-term FEIBA prophylaxis.
• To assess the safety and efficacy of FEIBA for preventing joint complications in hemophilia patients with inhibitors.

Main Methods:

• A study involving seven patients with high-titre Factor VIII inhibitors receiving FEIBA prophylaxis (50-100 units, 3-4 times weekly) for 3-6.5 years.
• Safety assessment included medical status, thrombosis, severe bleeding, and inhibitor titres.
• Efficacy was measured by functional joint evaluation and a physical therapeutic scale.

Main Results:

• All patients had pre-existing arthropathy at study initiation; joint progression and synovitis were observed despite prophylaxis.
• Two patients showed functional improvement in arthropathy; all patients maintained functionality for daily activities like attending school.
• FEIBA was deemed safe for long-term use, with no thrombosis, life-threatening bleeding, or FEIBA-induced complications. Inhibitor titres decreased.

Conclusions:

• FEIBA is safe for extended prophylactic use in hemophilia patients with Factor VIII inhibitors at recommended dosages.
• The study did not demonstrate efficacy in preventing arthropathy progression, likely due to pre-existing joint damage at prophylaxis initiation.
• Further research is recommended to investigate FEIBA's efficacy in preventing arthropathy before joint damage occurs.