Rescue Immunotolerance Study in Induction of Immune Tolerance (ITI)-Experienced Patients (RES.I.S.T. Experienced) (RESIST EXP)
|Study Design:||Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
|Official Title:||Immune Tolerance Induction Study in Patients With Severe Type A Haemophilia With Inhibitor After Failure of a Previous Induction of Immune Tolerance With FVII Concentrates Without Von Willebrand Factor Rescue|
- Achievement of an inhibitor titer of <0.6 BU/failure to achieve an inhibitor titer of <0.6 BU within 33 months, or failure to decrease inhibitor titer by at least 20% compared to titer in prior 6 months, beginning at 3 months after starting ITI [ Time Frame: 3 years ]Primary end point is the achievement of an inhibitor titer of less than 0.6 BU or failure to achieve an inhibitor titer of less than 0.6 BU within 33 months of treatment, or failure to decrease the inhibitor titer by at least 20% compared to the titer in the prior 6 months, beginning at 3 months after starting ITI
- Time to achieve success- either partial or complete. [ Time Frame: 33 months ]
- Safety - assessment of adverse events through treatment and compliance with prolonged regimen. [ Time Frame: 33 months ]Includes assessment and evaluation of adverse events occurring through treatment and compliance with a lengthy regimen
- Cost of care. [ Time Frame: Up to 45 months ]Direct cost will be calculated
|Actual Study Start Date:||September 23, 2009|
|Estimated Study Completion Date:||June 2020|
|Estimated Primary Completion Date:||June 2020 (Final data collection date for primary outcome measure)|
|Experimental: Factor VIII and von Willebrand Factor||
Drug: VWF/FVIII concentrates
200 IU/Kg by one or two bolus injections daily. After successful confirmation the dose will be tailed off progressively until discontinuation. Patients will be treated with a VWF/FVIII concentrates according to physician/patients preference.
The presence of Factor VIII (FVIII) inhibitor prevents FVIII infusions from working properly and makes treatment of bleeding episodes very difficult. Having an inhibitor is a serious and life-threatening complication in patients with Hemophilia. The usual treatment of patients with FVIII inhibitors involves what is called "immune tolerance induction" (ITI). Immune Tolerance means that the body can accept infused FVIII and that FVIII is again effective in controlling bleeds. ITI involves giving high doses of FVIII regularly until the inhibitor disappears. This treatment is not always effective. The inhibitor persists in about 1 in 5 patients who undergo ITI.
There are 2 types of FVIII concentrates: FVIII concentrates derived from human plasma, which contain VWF, and concentrates of FVIII without VWF. Both types of concentrates are commonly used to induce immune tolerance in patients with Hemophilia A. Retrospective studies on subjects who were treated with VWF containing Factor VIII concentrates after failing ITI with pure factor VIII concentrates, have shown that tolerance can be achieved in a large percentage of patients. This study will access prospectively whether treatment with a FVIII concentrate containing VWF given at a high dose (200 units per kilogram) daily for up to 33 months is able to induce immune tolerance after previous attempts with concentrates containing only FVIII have failed.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01051076
|United States, California|
|City of Hope Medical Center|
|Duarte, California, United States, 91010|
|Principal Investigator:||Nadia P. Ewing, MD||Clinical Professor of Pediatrics, City of Hope National Medical Center, Dept. of Pediatrics, 1500 E. Duarte Rd. Duarte, CA 91010|