Hemophilia
How is it treated?
The main treatment for hemophilia is replacing the clotting factor that is too low or missing. Clotting factors are given in differing doses according to the weight of the individual and the severity of the bleeding. Clotting factor products are powders that are packaged in sterile glass vials. Many of them require special storage such as refrigeration. When a dose is needed, the powder is dissolved in small amounts of sterile water and the resulting solution is either injected into a vein or mixed with a larger amount of fluid and dripped into a catheter that is inserted into a vein (an IV infusion).
In individuals who have mild forms of hemophilia, replacement therapy is generally not used, unless the individual is going to be participating in sports or is having a dental procedure done. With mild hemophilia, desmopressin (DDAVP) is the agent that is normally used. DDAVP is a synthetic hormone that releases von Willebrand factor which transports factor VIII thus increasing factor VIII levels. DDAVP is not really a clotting factor and is available in two forms: injection and nasal spray.
With moderate forms of hemophilia, clotting factor replacement should begin when bleeding starts, when bleeding is expected (e.g. surgery), and when participating in activities that increase the bleeding risk (e.g. contact sports). For individuals with moderate or severe hemophilia, prompt administration of the missing clotting factor reduces the risk of chronic complications that may result from repeated or prolonged bleeding episodes.
The clotting factors that are used in replacement therapy come from two sources. Many of the clotting factor products that are currently available are produced by recombinant DNA techniques. This process is carried out in sterile production facilities where the clotting factor genes are grown synthetically. Other clotting factor products are derived from human blood plasma. Clotting factors from human blood plasma have a slight chance of being contaminated with viruses such as HIV and hepatitis; therefore, recombinant clotting factors are usually preferred because they do not carry viruses. Manufacturers of human blood plasma-derived factor products include viral inactivation steps in the production process that greatly decrease the risk of viral contamination.
For treating hemophilia A, the following factor VIII products are currently available:
Recombinant Products:
- Advate
- Bioclate
- Helixate FS
- Kogenate
- Kogenate FS
- Recombinate
- ReFacto
Plasma-derived Products:
- Alphanate
- Hemophil M
- Humate-P
- Koate DVI
- Monarc-M
- Monoclate-P
The following factor IX products are currently available to treat hemophilia B:
Recombinant Product:
Plasma-derived products:
- AlphaNine SD
- Mononine
- Profilnine SD
Antibodies (also called inhibitors) to clotting factors develop in one-fourth to one-third of individuals with severe hemophilia A and 5% to 10% of individuals with severe hemophilia B. Antibodies are parts of the immune system that identify and attack foreign cells such as bacteria. When antibodies attack infused clotting factors, the effectiveness of the clotting factor may be decreased or even eliminated, which can lead to uncontrolled bleeding. Individuals with hemophilia who have antibodies to clotting factors may need to use an anti-inhibitor along with a clotting factor product.
The following products contain both a clotting factor and an anti-inhibitor:
Plasma-derived combination of anti-inhibitor and factor VIII:
Plasma-derived combination of anti-inhibitor and factors II, VIIa, IX and X:
Other combination products available to treat specific types of hemophilia are:
Blood-derived combination of anti-inhibitor and factors II, IX and X:
Other products that could be used for hemophilia:
- Novoseven
- Hyate: C (porcine VIII)
Other treatments can help aid the clotting factors, so that they work better are agents known as antifibrinolytics (pronounced ?an-tee-fye-bri-noh-lit-iks?). Antifibrinolytics help prevent formed clots from breaking down and include the following agents: Cyklokapron (tranexamic acid) and Amicar (aminocaproic acid). These agents work by blocking the factors that break up clots in the body and are typically used:
- Before dental procedures
- For nose bleed treatments
- For individuals that may be experiencing bleeding in the intestines (blood in the stools)
To learn more about the drugs used to treat hemophilia, click on the Drug Class links below.
Drug classes used to treat Hemophilia Factor IX Products Factor VIII Products Miscellaneous Hemophilia Products
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How is it treated?
