Haemophilia is a rare condition the blood’s ability to clot. It is genetic meaning that it is usually inherited and common mainly in men. People who have Haemophilia do not have as many clotting factors which are the proteins that help bleeding to stop along with platelets (blood cells) that combine to make the blood sticky inevitably making it stop. The main clotting factor that is not produced is called clotting factor VII.
A gene therapy trial which took place at Bart’s Health NHS Trust has helped patients with Haemophilia come off treatment. People who have Haemophilia have to carry out treatment in a form of an injection, usually three times a week. This treatment involves a genetically engineered clotting factor medicine used to prevent and treat prolonged bleeding. Of thirteen patients which took part in the trial eleven are now producing near-normal levels of proteins.
The therapy involves a genetically engineered virus. The virus contains the instruction to produce factor VIII (which in most cases patients are born without it is deficient). The virus then delivers instructions to the liver which is responsible for produce the specific type of protein. Low levels of the dose made no difference initially.
Professor John Pasi who lead the trials at Barts and Queen Mary University of London said: “This is ground-breaking because the option to think about normalising levels in patients with severe haemophilia is absolutely mind-blowing. To offer people the potential of a normal life when they’ve had to inject themselves with factor VIII every other day to prevent bleeding is transformational” Larger trials are now scheduled to help to treat more patients.