A Study to Investigate the Course of Synovial Hypertrophy in Patients With Haemophilia A on Efanesoctocog Alfa Prophylaxis

The rationale for conducting this open-label phase 4 study is to assess whether once-weekly prophylaxis with efanesoctocog alfa (50 IU/kg) improves the disease course of existing synovial hypertrophy and prevents the risk of joint bleeds in patients with moderate or severe haemophilia A. The use of imaging assessments will allow for objective detection and monitoring of synovial hypertrophy, and thus expand on the previous findings demonstrating positive effects of once-weekly prophylaxis with efanesoctocog alfa (50 IU/kg) on joint health.