Hydroxyurea for Children and Young Adults With Sickle Cell Disease and Pulmonary Hypertension

A Pilot Study of Hydroxyurea for the Treatment of Pulmonary Hypertension in Children and Young Adults With Sickle Cell Disease

The goal of this study is to test the hypothesis that hydroxyurea is effective for the specific treatment of secondary pulmonary hypertension found on screening in children and young adults with sickle cell disease.

Study Overview

• Status: Terminated
• Conditions: Sickle Cell Disease; Pulmonary Hypertension
• Intervention / Treatment: Drug: Hydroxyurea

Detailed Description

Increasing evidence suggests that pulmonary hypertension, defined by an elevated tricuspid regurgitant jet velocity (TRJV) on echocardiogram, is a major cause of morbidity and mortality in adults with sickle cell disease (SCD). However, both the prevalence and optimal treatment of pulmonary hypertension in children and young adults with SCD are unknown.

We hypothesize that short term therapy with hydroxyurea will decrease TRJV in children and young adults with pulmonary hypertension found on screening. Patients eligible for treatment will have had evidence of pulmonary hypertension on at least 2 screening echocardiograms. Baseline laboratory tests will be obtained and other causes of secondary pulmonary hypertension will be excluded prior to initiation of treatment. Patients will be treated with hydroxyurea according to a standard dose escalation schedule for a total of 12 months. A clinic visit will be required every 2 months and standard screening for toxicity will be performed monthly. There will be an interim analysis of the primary outcome at 6 months following therapy.

• Study Type: Interventional
• Enrollment (Actual): 6
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Ann & Robert H Lurie Children's Hospital of Chicago

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 10 years to 25 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age between 10 and 25 years old
• Sickle cell disease with hemoglobin SS, SC or S-B^0 thalassemia confirmed on hemoglobin electrophoresis
• Tricuspid regurgitant jet velocity (TRJV) equal to or greater than 2.5 m/sec on 2 baseline Doppler echocardiograms at least 3 months apart

Exclusion Criteria:

• Patients already being treated with hydroxyurea
• Patients on a chronic transfusion protocol
• Patients with evidence of hepatic (alanine aminotransferase [ALT] equal to or greater than 2 SD above normal) or renal dysfunction (creatinine [Cr] equal to or greater than 2 SD above normal)
• Patients who are pregnant
• Patients with documented causes of severe pulmonary hypertension other than from SCD

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Hydroxyurea; Single arm pilot of hydroxyurea in the experimental arm with starting dose of 20 mg/kg/day po and dose escalation every 2 months until maximum tolerated dose.	Drug: Hydroxyurea; Drug to be initiated at standard starting dose with dose escalation until maximum tolerated dose reached.; Other Names: Experimental arm

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Mean Reduction in TRJV at M6	6 months after initiation of hydroxyurea
Mean Reduction in TRJV at M12	12 months after initiation of hydroxyurea

Secondary Outcome Measures

Outcome Measure	Time Frame
Mean Increase Hb F% at M6	6 months after initiation of hydroxyurea
Mean Increase in HbF% at M12	12 months after initiation of hydroxyurea
Mean Reduction in LDH at M6	6 months after initiation of hydroxyurea
Mean Reduction in LDH at M12	12 months after initiation of hydroxyurea
Mean Reduction in Retic% at M6	6 months after initiation of hydroxyurea
Mean Reduction in Retic% at M12	12 months after initiation of hydroxyurea

Collaborators and Investigators

• Sponsor: Ann & Robert H Lurie Children's Hospital of Chicago
• Investigators: Principal Investigator: Robert I Liem, MD, Ann & Robert H Lurie Children's Hospital of Chicago

Study record dates

Study Major Dates

• Study Start: July 1, 2006
• Primary Completion (Actual): June 1, 2008
• Study Completion (Actual): June 1, 2008

Study Registration Dates

• First Submitted: July 10, 2006
• First Submitted That Met QC Criteria: July 10, 2006
• First Posted (Estimated): July 11, 2006

Study Record Updates

• Last Update Posted (Actual): September 24, 2026
• Last Update Submitted That Met QC Criteria: August 31, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: Pulmonary Hypertension; Sickle Cell Disease
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Genetic Diseases, Inborn; Respiratory Tract Diseases; Lung Diseases; Hematologic Diseases; Anemia, Hemolytic, Congenital; Anemia, Hemolytic; Anemia; Hemoglobinopathies; Hypertension; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Hemic and Lymphatic Diseases; Anemia, Sickle Cell; Hypertension, Pulmonary; Organic Chemicals; Amides; Urea; Hydroxyurea
• Other Study ID Numbers: 12735

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No