Hemophilia A, a drug for reducing bleeding even in mild and moderate forms

FROM the congress of the International Society on Thrombosis and Haemostasis (ISTH), which was held in recent days, new confirmations arrive for the drug emicizumab in the fight against haemophilia A. The antibody, designed to restore the coagulation process, has been shown to safe and effective even in patients with mild and moderate haemophilia A. To the point that the data presented, coming from the HAVEN 6 study, will be used to ask the European Medicines Agency (Ema) to update its indications, also including patients with non-severe haemophilia A, as is already the case in several countries around the world.

Hemophilia A

Hemophilia is a hereditary blood disorder due to the total or partial absence of a coagulation factor and the consequent presence of bleeding affecting different parts of the body, from the muscles, to the gums, to the joints. Hemophilia A, the most common among hemophilias, is due to a lack of coagulation factor VIII. About a third of cases have a severe form, that is, the clotting factor is almost completely or almost completely missing. The rest are mild or moderate forms, in which the coagulation factor is present, but in small quantities. “To date, limited information and indications are available on the treatment of patients with moderate or mild haemophilia A, in which the diagnosis of bleeding may be delayed or adequate continuous prophylaxis may be lacking, regardless of the severity of the coagulation defect”, recalled Giancarlo Castaman, director of the Hemorrhagic and Coagulation Diseases Center, Careggi University Hospital of Florence. Many of these patients, in fact, may not receive preventive treatments, with the risk of bleeding and worsening, as evidenced by other studies carried out in London.

Emicizumab for mild and moderate forms

The data arriving from London had already been anticipated at the congress of the American Society of Hematology and concern about seventy people with mild or moderate forms, without factor VIII inhibitors (inhibitors are a resistance response to classical therapies, based on factor VIII VIII): after more than one year of median follow-up, 66.7% of participants did not experience bleeding requiring treatment, 81.9% did not experience spontaneous bleeding requiring treatment, and 88, 9% did not experience joint bleeding requiring treatment. All this in the face of a substantially unchanged safety profile consistent with what was previously observed. “The new data from the HAVEN 6 study show clinically significant bleeding event prevention, in line with previous HAVEN studies in severe patients, with or without an FVIII inhibitor. These data confirm the potential of emicizumab to redefine the standard of care for all people living with haemophilia A of any severity, enabling them to strive for a better quality of life ”.