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Severe Haemophilia A

Haemophilia is a rare genetic disease, with the main types caused by a mutation in the gene that provides instructions to make a protein called factor VIII or factor IX, which is essential for blood to clot normally.1 Without enough clotting factors, people living with haemophilia experience spontaneous bleeds, which can result in progressive and debilitating joint damage.2

What is Haemophilia?

Haemophilia is a rare condition that affects the blood’s ability to clot. Normally, when blood vessels are injured, clotting factor is a protein in blood that controls bleeding.1 People with haemophilia are missing or have low levels of clotting factors, leaving them at risk of spontaneous bleeding, as well as excessive bleeding from minor cuts, falls or even daily activities.3

The two main types of haemophilia are A and B. Of the two, haemophilia A is the more common, occurring in 1 in 10,000 people, while haemophilia B occurs in 1 in 50,000.4 People with haemophilia A are missing or have low levels of clotting factor VIII. People with haemophilia B are missing or have low levels of clotting factor IX.4

Symptoms of Haemophilia

The symptoms of haemophilia are the same across haemophilia A and B, and include having large bruises, bleeding into muscles and joints, prolonged bleeding after getting a cut, and spontaneous bleeding, where bleeding occurs suddenly within the body for no clear reason.1

People with moderate or severe haemophilia have levels of clotting factor below 5% of someone without haemophilia, and live with the constant fear of spontaneous bleeds, which can, in some cases, be life-threatening.5,6

Even with treatment, many people with haemophilia continue to experience micro-bleeds in their joints, which cause progressive damage over time.7,8 This is extremely painful and can result in people being unable to take part in day-to-day activities, suffering from depression or anxiety, and living a life in which pain is a constant feature.9

Diagnosing Haemophilia

Haemophilia is diagnosed through a series of blood tests to measure the level of clotting factor activity.10

Haemophilia is usually inherited, meaning that it is passed on through a parent’s genes. If there is a family history of haemophilia, tests can be carried out during pregnancy.10 Sometimes haemophilia can occur when there is no family history, which is called sporadic haemophilia and is the case for around 40% of people with haemophilia.11 In these cases, it may take years for a patient with mild or moderate haemophilia to be diagnosed, while people living with severe haemophilia are usually diagnosed within their first year of life.10

Managing Haemophilia

Severe haemophilia is a lifelong condition that comes with serious complications and a relentless treatment burden, which can have a psychological impact on both patients and caregivers.9

People living with haemophilia need to replace the missing clotting factor. In the past this came from plasma, while today many haemophilia patients are treated with recombinant, or synthetic, clotting factor replacement therapy, although this can be unavailable in countries with limited health resources.12

Patients typically require routine intravenous infusions 2-3 times per week to maintain target levels of clotting factors, and many struggle to commit to this time-intensive routine.13,14 Even on newer non-factor replacement therapies, injections can still be required from once a week to twice a month.14

In addition, approximately 30% of people living with haemophilia will develop an inhibitor to their treatment, meaning their body will reject this, leaving them without a treatment option.11

The treatment of severe haemophilia can require significant resources, with haemophilia treatment centres featuring teams of doctors, nurses, physiotherapists, as well as potentially psychologists and social workers.15

There have been recent research and advances in treatment to address these challenges, from recombinant products with extended half lives, to substitution therapies which restore the function of the missing factor.16


References
  1. World Federation of Haemophilia. Introduction to Haemophilia. Available at: https://elearning.wfh.org/elearning-centres/introduction-to-hemophilia/#what_is_hemophilia. Last accessed June 2021.
  2. Uijl I et al. Outcome in moderate haemophilia. Blood Transfus 2014;12(Suppl 1):s330-s336.
  3. National Hemophilia Foundation. Hemophilia A. Available at: https://www.hemophilia.org/Bleeding-Disorders/Types-of-Bleeding-Disorders/Hemophilia-A. Last accessed June 2021.
  4. Makris M et al. The European Haemophilia Network (EUHANET). Blood Transfus 2014;12(Suppl 3):s515-s518.
  5. NHS UK. Haemophilia Symptoms. Available at: https://www.nhs.uk/conditions/haemophilia/symptoms/. Last accessed June 2021.
  6. Franchini M et al. Past, present and future of hemophilia: a narrative review. Orphanet J Rare Dis 2012;7:24.
  7. duTreil S. Physical and psychosocial challenges in adult hemophilia patients with inhibitors. J Blood Med 2014;5:115-22.
  8. Manco-Johnson M et al. Prophylaxis versus episodic treatment to prevent joint disease in boys with severe hemophilia. N Engl J Med 2007;357:535-44.
  9. O’Hara J et al. Associated impact of activity impairment on clinical and patientcentric outcomes in severe hemophilia. Haemophilia 2018;24:1.
  10. The Haemophilia Society. How is haemophilia diagnosed? Available at: https://haemophilia.org.uk/bleeding-disorders/faqs/how-is-haemophilia-diagnosed/. Last accessed June 2021.
  11. European Haemophilia Consortium. Haemophilia. Available at: https://www.ehc.eu/bleeding-disorders/haemophilia/. Last accessed June 2021.
  12. Noone D et al. Evolution of haemophilia care in Europe: 10 years of the principles of care. Orphanet J Rare Dis 2020;15:184.
  13. Srivastava A et al. Guidelines for the management of Hemophilia. Haemophilia 2013;19(1):e1-47.
  14. Mahlangu J et al. Emicizumab prophylaxis in patients who have hemophilia A without inhibitors. N Engl J Med 2018;379:9.
  15. The Haemophilia Society. Who will be involved in care of those living with haemophilia? Available at: https://haemophilia.org.uk/bleeding-disorders/faqs/who-will-be-involved-in-care-of-those-living-with-haemophilia/. Last accessed June 2021.
  16. Weyand A et al. New therapies for hemophilia. Blood 2019;133(5):389-98.

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