Prophylaxis is the name given to regular treatment to prevent bleeds. For someone with haemophilia, this is treatment, typically 3 times a week, which helps the blood clot and minimises the likelihood of bleeds and long-term joint damage.

Those people with moderate haemophilia rarely have spontaneous bleeds, so the principal goal of prophylaxis is to effectively convert a patient with severe haemophilia to moderate haemophilia by administering factor regularly.

Prophylaxis is hugely important for people living with haemophilia. Severe haemophiliacs who experience spontaneous bleeds into joints may sustain long-term damage such as arthritis, with certain joints becoming more vulnerable to ‘target’ joints.