Effects of Nitric Oxide and Nitroglycerin in Patients With Sickle Cell Anemia

• Status: Completed
• Trial end date: 2003-07-01
• Target enrollment: 0
• Participant gender: All

Summary

Sickle cell anemia is the most common genetic disease affecting African-Americans. About 1 in every 1000 African-Americans has the disease and 1 in every 12 carry the genes that could be passed on to their children. People with sickle cell anemia have abnormal hemoglobin, the molecules responsible for carrying oxygen in the blood. The abnormal hemoglobin can cause damage to the red blood cells. The damaged red blood cell may then stick in the blood vessels and cause pain and injury to organs. Some of the complications caused by the sticking of blood cells are called acute pain crisis and acute chest syndrome (ACS).

Nitric oxide (NO) is a gas that has been proposed as a possible therapy for the ACS complication of sickle cell anemia. Studies have shown that NO may favorably affect sickle cell hemoglobin molecules, thereby improving blood flow through small vessels.

This study is designed to evaluate the effects of NO, when taken in combination with a drug called nitroglycerin on patients with sickle cell anemia and normal volunteers. The effects of these two drugs only last while the patient is receiving them. Researchers hope the information learned from this study will help to develop new therapies for sickle cell anemia.

• Phase: Phase 2
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: National Institutes of Health Clinical Center (CC)
• Treatments: Nitric Oxide; Nitroglycerin

Criteria

INCLUSION CRITERIA:

Males or females 18 to 65 years of age.

Diagnosis of sickle cell disease (electrophoretic documentation of SS homozygosity is required) or identification as a normal volunteer.

Hematocrit greater than 18% (with an absolute reticulocyte count greater than 100,000/ml).

Hematocrit 18-21% (with an absolute reticulocyte count greater than 100,000/ml): Only 100 ml of blood may be drawn. The study subject may be re-entered in the study after four weeks (with repeat full screening labs).

EXCLUSION CRITERIA:

Clinically unstable sickle cell anemia defined by the following:

Having greater than two acute pain crises in the last two months; on hydroxyurea or butyrate therapy any time in the last 12 months; or blood transfusion within last three months, or % hemoglobin A greater than 20%.

Age less than 18 years or greater than 65 years.

Current pregnancy or lactation.

Inability to exercise the anterior tibialis muscle.

Active cigarette smoker-defined as the inhalation of smoke from any tobacco product in the last one month.

Medical conditions: diabetes mellitus; coronary artery disease; peripheral vascular disease; migraine headaches in the last 12 months; history of previous CVA or stroke; or creatinine greater than 1.0 mg/dL.

MRI Exclusions: cardiac pacemaker or implantable defibrillator; aneurysm clip; neural stimulator (e.g. TENS-Unit); any type of ear implant; or metal in the eye (e.g. from machining); any implanted device (e.g. insulin pump, drug infusion device); or any metallic foreign body, shrapnel, or bullet.

Hematocrit less than or equal to 18 percent: will not be eligible for the study; may return for evaluation at a later date.

No aspirin or non-steroidal anti-inflammatory drugs (no NSAIDS and caffeine the day of the study.) Patients on opiates and acetaminophen will not be excluded.

Patients taking Viagra will be excluded from the study.