Viewing Study NCT00001958



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Last Modification Date: 2024-10-26 @ 9:02 AM
Study NCT ID: NCT00001958
Status: COMPLETED
Last Update Posted: 2008-03-04
First Post: 2000-01-18

Brief Title: Hydroxyurea to Treat Beta-Thalassemia Cooleys Anemia
Sponsor: National Institute of Diabetes and Digestive and Kidney Diseases NIDDK
Organization: National Institutes of Health Clinical Center CC

Study Overview

Official Title: Effect of Hydroxyurea on the Level of Ineffective Erythropoiesis Transfusion Requirement and Fetal Hemoglobin Synthesis in Patients With Beta-Thalassemia-Intermedia
Status: COMPLETED
Status Verified Date: 2002-02
Last Known Status: None
Delayed Posting: No
If Stopped, Why?: Not Stopped
Has Expanded Access: False
If Expanded Access, NCT#: N/A
Has Expanded Access, NCT# Status: N/A
Acronym: None
Brief Summary: This 12-month study will evaluate the safety and effectiveness of hydroxyurea in treating beta-thalassemia a type of anemia caused by defective hemoglobin the oxygen-carrying pigment in blood Hemoglobin is composed of two protein chains-alpha globin chains and beta globin chains patients with beta-thalassemia do not make beta globin Patients often require frequent red blood cell transfusions This leads to iron overload which in turn requires iron chelation therapy removal of iron from the blood

Some drugs including hydroxyurea can stimulate production of a third type of protein chain called gamma chains In the womb the fetus makes this type of protein instead of beta globin It is not until after birth when the fetus no longer produces gamma globin that the beta globin deficiency becomes apparent Gamma chain synthesis improves hemoglobin and red blood cell production correcting the anemia This study will determine if and at what dose hydroxyurea treatment reduces patients need for red blood cell transfusions and whether certain factors might predict which patients are likely benefit from this treatment

Patients 15 years and older with moderately severe beta-thalassemia may be eligible for this study Participants will take hydroxyurea daily at a dose calculated according to the patients body size Blood will be drawn weekly to measure blood cell and platelet counts The drug dosage may be increased after 12 weeks of treatment and again after 24 weeks if the white cell and platelet counts remain stable Patients who respond dramatically to treatment may continue to receive hydroxyurea for up to 3 years
Detailed Description: Individuals with homozygous beta thalassemia are either severely anemic or dependent on blood transfusion to sustain life Deficient synthesis of the beta chain leads to imbalanced chain synthesis with an excess of alpha globin This alpha globin precipitates causing ineffective erythropoiesis and shortened red cell survival Hydroxyurea is a cell-cycle specific agent that blocks DNA synthesis by inhibiting ribonuclease reductase the enzyme that converts ribonucleotides to deoxyribonucleotides Administration of hydroxyurea to primates and more than 300 patients with sickle cell anemia has been frequently but not invariably associated with a substantial increase in synthesis of gamma globin In patients with homozygous beta-thalassemia enhanced gamma globin synthesis could partially compensate for the deficient synthesis of beta globin rendering chain synthesis more balanced and reducing the relative excess of alpha chains The purpose of this protocol is to test the hypothesis that chronic daily low dose administration of hydroxyurea will enhance gamma globin synthesis increase red cell production and partially or substantially correct the anemia in patients with homozygous beta-thalassemia The effect of treatment will be monitored by serial determination of the hemoglobin and hematocrit The relationship between response to therapy and the specific beta-globin mutations will also be analyzed This study will therefore examine a cohort of patients not previously treated with hydroxyurea

Study Oversight

Has Oversight DMC: None
Is a FDA Regulated Drug?: None
Is a FDA Regulated Device?: None
Is an Unapproved Device?: None
Is a PPSD?: None
Is a US Export?: None
Is an FDA AA801 Violation?: None
Secondary IDs
Secondary ID Type Domain Link
00-DK-0040 None None None