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Stroke Prevention in Sickle Cell Anemia (STOP 1)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00000592
Recruitment Status : Completed
First Posted : October 28, 1999
Last Update Posted : December 23, 2015
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by:
Augusta University

Brief Summary:
To reduce episodes of first time stroke by 75 percent in children with sickle cell anemia by the administration of prophylactic transfusion therapy.

Condition or disease Intervention/treatment Phase
Anemia, Sickle Cell Cerebral Embolism and Thrombosis Cerebrovascular Disorders Hematologic Diseases Hemoglobinopathies Procedure: blood transfusion Phase 3

Detailed Description:


Stroke, occurring in about 10 percent of pediatric patients with sickle cell disease, is one of the most devastating complications, with a high recurrence rate after the first episode. Several non-randomized studies have shown reduction in stroke recurrence when periodic blood transfusions are administered to maintain hemoglobin S under 30 percent. Periodic blood transfusions are associated with significant risks of iron overload and other complications and must be accompanied by parenteral iron chelation therapy. However, this has become a standard of care for prevention of recurrent stroke in SS children. Thus, a randomized trial of blood transfusion for secondary prevention would not be feasible because it would be considered unethical. Based on various studies, the recurrence rate is reduced from 46 to 67 percent to approximately 7 percent on transfusion therapy. Because most stroke patients are left with some neurological deficit, and face a lifetime of disability, primary prevention would have a significant impact on the management of patients. However, because of complications of blood transfusions, the hypothesis should be proven by a randomized clinical trial.

A primary prevention trial had not been possible because an acceptable means of detecting those children at risk of stroke was not available. The advent of TCD to identify arterial abnormalities for the prediction of stroke has provided a means of detection. TCD abnormalities have a high specificity (100 percent) and high sensitivity (90 percent) for detecting angiographically proven narrowing of arterial diameter. Thus, TCD examination of the basal cerebral arteries is predictive of who will develop a stroke.


Randomized, Phase III, multicenter. Approximately 3,000 children from 12 clinics were screened with transcranial Doppler (TCD). A total of 130 were randomized to receive either standard supportive care or periodic blood transfusions if they were found to be at high risk of stroke on the basis of elevated cerebral blood flow as measured by TCD screening tests. Primary endpoints included clinically evident symptoms of cerebral infarction with consistent findings on magnetic resonance imaging (MRI), and/or symptomatic intracranial hemorrhage. Secondary endpoints included asymptomatic brain lesions detected by MRI in brain areas not involved in primary endpoints. Hematologic characteristics of the high risk group were analyzed and serum and DNA samples frozen for future analysis. Recruitment ended in October 1997 with the accrual of 130 subjects. The clinical phase ended in 1999.

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Study Type : Interventional  (Clinical Trial)
Allocation: Randomized
Primary Purpose: Prevention
Study Start Date : July 1994
Study Completion Date : August 2000

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Anemia

Information from the National Library of Medicine

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Ages Eligible for Study:   2 Years to 16 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Pediatric patients, ages 24 months to 16 years, with sickle cell anemia or S-beta zero thalassemia.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00000592

Sponsors and Collaborators
Augusta University
National Heart, Lung, and Blood Institute (NHLBI)
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OverallOfficial: Donald Brambilla New England Research Institute Inc.


Publications automatically indexed to this study by Identifier (NCT Number):
Layout table for additonal information Identifier: NCT00000592    
Other Study ID Numbers: 312
U01HL052193 ( U.S. NIH Grant/Contract )
First Posted: October 28, 1999    Key Record Dates
Last Update Posted: December 23, 2015
Last Verified: November 2005
Additional relevant MeSH terms:
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Cerebrovascular Disorders
Intracranial Embolism
Intracranial Embolism and Thrombosis
Embolism and Thrombosis
Hematologic Diseases
Anemia, Sickle Cell
Vascular Diseases
Cardiovascular Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Genetic Diseases, Inborn
Anemia, Hemolytic, Congenital
Anemia, Hemolytic