Danicopan with eculizumab or ravulizumab for treating paroxysmal nocturnal haemoglobinuria

Danicopan is in clinical development as an add-on therapy to eculizumab or ravulizumab for the treatment of adult patients with paroxysmal nocturnal haemoglobinuria (PNH). PNH is a rare, long-term and life-threatening blood disease in which red blood cells (RBCs) are attacked by a group of proteins in the body’s immune system, which are collectively known as complement proteins. This attack by complement proteins results in excessive breakdown of RBCs (haemolysis) and leads to a large amount of haemoglobin (the protein found in RBCs that carries oxygen around the body) being released into the urine. The condition is caused by a mutation (DNA change) that results in a lack of certain proteins being present on the surface of RBCs that normally protect them from being destroyed by complement proteins. Symptoms of PNH can include anaemia, breathlessness, difficulty swallowing, fatigue, blood clots and kidney damage. Some patients do not respond adequately to current treatment with eculizumab or ravulizumab alone, so there is a need to develop additional treatment options for PNH.