Gene therapy for patients with haemophilia

Numerous factor products are now available for factor therapy, which can be tailored to the individual circumstances of each patient. This has greatly improved the quality of life of those affected over the last few decades, significantly reducing long-term damage caused by joint or muscle bleeding. Factor therapy is carried out at home by parents or by the patients themselves.

In addition, an antibody that mimics and replaces factor VIII has been available for several years. This application is administered subcutaneously once or twice a week.

Although significant progress has been made, all existing forms of treatment are classified as replacement therapies. They cannot cure haemophilia. This replacement therapy must be continued for the rest of the patient's life.

Vector-mediated gene therapy

Major advances have been made in gene therapy for haemophilia over the last 10 years. Gene therapy is now increasingly available to patients with severe and moderate haemophilia A and B within the scope of therapeutic studies.

The procedure involves replacing the defective gene for factor VIII or factor IX with the intact gene using what is known as vector-mediated gene therapy. To this end, the intact factor VIII/IX gene is inserted into the viral envelope of the adeno-associated virus (AAV), which is harmless to humans, and administered to the patient as a brief infusion.

This vector enters the liver cell and transports the intact gene into the cell, where it remains as ring DNA, allowing the intact factor VIII/IX to be produced. The gene is not integrated into the individual's own genetic material.

Moderating therapy

Patients treated so far have shown consistently high factor activity of more than 10 per cent over an observation period of up to 10 years. Severe haemophilia is moderated to mild haemophilia or even sub-haemophilia. This means that patients no longer require regular factor replacement treatment to prevent bleeding.

UKR: Selected as an infusion centre to perform gene therapy on adults and children with severe and moderate haemophilia A or B

Our Paediatric Centre has been selected as an infusion centre for the administration of gene therapy to adults and children with severe and moderate haemophilia A or B. While several gene therapy studies have been successfully conducted in adults in recent years, this curative therapeutic approach is now also being considered for adolescents for the first time.

Gene therapy will be offered to adolescents as part of clinical trials, while gene therapies for haemophilia A and B are now also approved for therapeutic prescription and use in Europe for adults.