Study Arm I
- Participant is male age two (2) or older (Study Arm I) or of any age and any race/ethnicity (Study Arm II)
- Participant has a diagnosis of Hemophilia A (Study Arm I) or Hemophilia A or B (Study Arm II) with a baseline factor activity level less than 50% of normal.
- Participant has not participated in HIRS Phase I or Phase II (Study Arm I)
This study is enrolling participants who have hemophilia. Some people with hemophilia do not accept factor infusions very well. This condition is caused by an inhibitor. Doctors don’t know very much about why inhibitors happen. Some studies have shown that changes in the hemophilia gene and that some types of hemophilia treatment may cause an inhibitor. The doctors in this study hope to find out why people get an inhibitor so they can try to prevent them. The primary purpose(s) of this study is to look into what might cause inhibitors to develop and to learn more about how inhibitor levels progress. This study will have an Arm I and Arm II.
- To asses risk disparities accounting for the two fold higher frequency of inhibitors in African American and Hispanic patients relative to non- Hispanic White patients.
- To learn more about the natural history of elevated inhibitor titers, in order to more clearly delineate characteristics of transient inhibitors and false positives from clinically significant inhibitors.
Eligibility criteria (Arm I)
- Participant is male age two (2) or older.
- Participant has a diagnosis of Hemophilia A with a baseline factor activity level less than 50% of normal.
- Participant has a history of a negative inhibitor or a positive inhibitor titer greater than or equal to 1.0 BU or NBU on two (2) occasions or a measured inhibitor titer greater than or equal to 1.0 BU or NBU and prescribed immune tolerance therapy.
- Participant has not participated in HIRS Phase I or Phase II.
- Participant has received an infused treatment product.
Eligibility criteria (Arm II)
- Participant has a newly elevated inhibitor titer defined as having a measured inhibitor titer greater than or equal to 0.5 BU or NBU for hemophilia A or greater than or equal to 0.3 BU or NBU for Hemophilia B on at least one occasion.
- Participant does not have a history of an inhibitor.
- Participant has a diagnosis of Hemophilia A or Hemophilia B with a baseline factor activity level less than 50% of normal.
- Participant is a male of any age and any race/ethnicity.
For the current eligibility status of this clinical study, referring physicians must contact St. Jude Children's Research Hospital at 1-866-2ST-JUDE (1-866-278-5833).
St. Jude Children’s Research Hospital
262 Danny Thomas Place
Memphis, TN 38105 USA
Voice: 1-888-226-4343 or 901-595-4055
24-Hour Emergency Access Pager: 1-800-349-4334
The above information is intended to provide only a basic description about a research protocol that may be currently active at St. Jude. The details made available here may not be the most up-to-date information on protocols used by St. Jude. To receive full details about a protocol and its status and or use at St. Jude, a physician must contact St. Jude directly.