Haemophilia A is an X-linked hereditary bleeding disorder caused by a deficiency of factor VIII (FVIII) which, if left untreated, may lead to haemorrhages in muscles and joints and consequently to arthropathy and severe morbidity. The disorder affects around one in every 10,000 males worldwide. Prophylaxis with replacement FVIII therapy reduces the number of bleeding episodes and the risk of permanent joint damage.