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Hemophilia A

What is Hemophilia A?

Hemophilia A is the most common type of hemophilia and is caused by deficient or dysfunctional clotting factor VIII. Although hemophilia A is usually inherited, about 30% of cases are caused by a spontaneous mutation in the person’s own genes. 

Hemophilia A affects about 1 in 12,000 people and is diagnosed by taking a blood sample and measuring the level of factor activity in the blood. Hemophilia A is diagnosed by testing the level of factor VIII activity in the blood. 

Hemophilia A can be mild, moderate, or severe, depending on how much clotting factor is in an affected person's blood. However, about 60% of patients have the severe form of the disorder. People with hemophilia A have prolonged bleeding after an injury, surgery, or tooth extraction. In severe cases, they may bleed once or twice a week and often the bleeding is spontaneous, which means it happens for no obvious reason. Serious complications can result from bleeding into the joints, muscles, brain, or other internal organs. In a mild case of hemophilia A, the disorder may remain unknown until after a surgery or serious injury.

Treatment for hemophilia A is very effective and with appropriate treatment and care, people with hemophilia A can live perfectly healthy lives. The main treatment is called replacement therapy, during which clotting factor VIII is infused into a vein either prophylactically (preventatively) or on-demand to prevent or treat bleeds.

Hemophilia A patient Tim Grams

Living with Severe Hemophilia

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Resources for you

Resource Description  
AFSTYLA Facebook Page Provides Hemophilia A patients and their families with information on AFSTYLA, patient stories and support programs. Go to Facebook
World Federation of Hemophilia A global organization aiming to improve and sustain care for people with inherited bleeding disorders. View Website
National Hemophilia Foundation A U.S. organization dedicated to finding better treatments and cures for inheritable bleeding disorders. View Website
Hemophilia Federation of America A U.S. nonprofit organization that assists and advocates for the bleeding disorders community. View Website
Product Websites (United States) (United States) (Germany)


Treatments Available

Availability of treatments may vary from country to country. Please be sure to visit your local site for further information.

AFSTYLA® | Antihemophilic Factor (Recombinant), Single Chain

US Prescribing Information

US Important Safety Information(Selected) 

Immediately stop treatment with AFSTYLA and contact your healthcare provider if you see signs of an allergic reaction, including a rash or hives, itching, tightness of chest or throat, difficulty breathing, lightheadedness, dizziness, nausea, or a decrease in blood pressure.

In clinical trials, dizziness and allergic reactions were the most common side effects. However, these are not the only side effects possible. Tell your healthcare provider about any side effect that bothers you or does not go away.

Full US Important Safety Information

 Humate-P® | Antihemophilic Factor/von Willebrand Factor Complex (Human)
 Known outside the US as: Haemate® P 

US Prescribing Information

US Important Safety Information(Selected) 

Do not take Humate-P if you have had extreme sensitivity or an allergic response to antihemophilic or von Willebrand factor preparations. Your doctor will monitor you for events related to abnormal blood clotting.

In studies, more than 5% of patients reported the following adverse reactions to Humate-P: allergic/anaphylactic reactions, including hives, chest tightness, rash, itching, and swelling. The most common adverse reactions after surgery were bleeding at the wound or infusion site, and nosebleeds.

Full US Important Safety Information

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