Assessment of Algorithm-Based Hydroxyurea Dosing on Fetal Hemoglobin Response, Acute Complications, and Organ Function in People With Sickle Cell Disease

• Status: Completed
• Trial end date: 2018-05-24
• Target enrollment: 0
• Participant gender: All

Summary

Background:

• Sickle cell disease (SCD) is a blood disease. The drug hydroxyurea (HU) is approved to prevent pain crises in people with SCD. Researchers want to see how higher doses of HU affect the blood. This will help them learn about the right dosage of HU to give to people with SCD.

Objective:

• To improve hydroxyurea dosing in people with SCD.

Eligibility:

• People age 15 or older with homozygous SCD (HbSS).

Design:

• Participants will be screened with medical history, physical exam, medication review, and blood and urine tests.

• Participants will be in the study for about 15 months.

• First 3 months: monthly study visits with blood and urine tests.

• After 3 months: participants will take HU as a capsule by mouth. If you are already taking HU, your dose will be increased.

• Within a month of starting or increasing HU: participants will keep a daily pain diary for 2 weeks. They will have an echocardiogram (ultrasound) of the heart, a 6-minute walk test. They will complete a quality-of-life questionnaire.

• Participants will visit every month until they reach their highest tolerated dose of HU. They may need to come as often as every week sometimes to closely monitor their blood counts. Then they will alternate a phone call one month and a visit the next. At the visits, participants will bring their pill bottle, answer questions about side effects, and have blood tests.

• Every 2 months, participants will have a medical history, physical exam, and blood tests.

• Every 4 months, participants will have blood and urine tests. They will also complete another 2-week pain diary and quality-of-life questionnaire.

• About 12 months after starting or increasing HU, participants will have blood tests, an echocardiogram, and a 6-minute walk test.

• Phase: Phase 1/Phase 2
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: National Heart, Lung, and Blood Institute (NHLBI)
• Treatments: Hydroxyurea

Criteria

• INCLUSION CRITERIA:

1. Age greater than or equal to 15 years

2. Homozygous sickle cell disease (HbSS)

3. Patients with recent transfusion must have HbA <15% prior to enrollment

4. ANC greater than or equal to 2,000/microL, platelets greater than or equal to150,000/microL, Hb > 5.4g/dL, and ARC greater than or equal to100,000/microL (unless the Hb is > 8g/dL) at baseline

5. Patients on angiotensin-converting enzyme inhibitors and angiotensin receptor blockers should be on a stable dose for 2 weeks prior to initiating or adjusting HU

EXCLUSION CRITERIA:

1. Pregnant or lactating women or patients planning to get pregnant during the study period

2. Patients unwilling to use two forms of contraception throughout the period of HU administration

3. Patients receiving chronic transfusion therapy

4. Patients receiving a HU dose of greater than or equal to 20 mg/kg/day

5. Patients with history of allergy or intolerance to HU judged by the investigator to be prohibitive against restarting HU

6 Patients with end stage renal disease defined as GFR <10mL/min/1.73m(2)

7. Patients being treated with antiretroviral agents (such as didanosine and stavudine) because of a higher risk for potentially fatal pancreatitis, hepatic failure, hepatitis, and severe peripheral neuropathy when co-administered with hydroxyurea.

8. Participation on any other chronic investigative treatment studies

9. Unable to understand the investigational nature of the study or give informed consent.