Hemophilia B

What is Hemophilia B?

Hemophilia B (or Christmas disease) is less common than hemophilia A and results when the person does not have enough clotting factor IX. Although hemophilia B is usually inherited, about 30% of cases are caused by a spontaneous mutation in the person’s own genes. 

Hemophilia B affects about 1 in 50,000 people and is diagnosed by taking a blood sample and measuring the level of factor activity in the blood. 

Hemophilia B 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 B 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 mild case of hemophilia B, the disorder may remain unknown until after a surgery or serious injury.

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

Here is a sampling of our Vita stories on Hemophilia:

To read all of our stories, please visit our Vita homepage.

Perry Parker
Don't Let Hemophilia Hold You Back

Pro golfer Perry Parker’s tips for pursuing dreams despite a rare disease.

Hemophilia patient Michael at a swimming pool
Going to School with Hemophilia

Five ways to help your child succeed.

Video freezeframe of a hemophilia animation.
Female Carriers of Hemophilia

Women with a family history of hemophilia could see symptoms like abnormal bleeding.

Resources for you

IDELVION Facebook Page Provides Hemophilia B patients and their families with information on IDELVION, patient stories and support programs. View Website  
Signs of Bleeding The 5 signs of a bleeding disorder View Website
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. national nonprofit organization that assists and advocates for the bleeding disorders community. View Website
Product Websites IDELVION (United States)

Treatments Available

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

IDELVION® Coagulation Factor IX (Recombinant), Albumin Fusion Protein Visit Website pdf
Mononine® Coagulation Factor IX (Human) Monoclonal Antibody Purified   pdf
Berinin® P    Visit Website  

Current Clinical Trials

Condition Description    
Hemophilia B A Safety and Efficacy Extension Study of a Recombinant Fusion Protein Linking Coagulation Factor IX With Albumin (rIX-FP) in Patients With Hemophilia B Learn More
Group meeting

Participate in Clinical Trials

Discover what is involved in participating in one of our clinical trials and how you can enroll.

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