Hydroxyurea for Sickle Cell Anemia

(TREAT Trial)

Overseen By Amanda Pfeiffer, LPC, CCRP

Age: < 65

Sex: Any

Trial Phase: Academic

Sponsor: Children's Hospital Medical Center, Cincinnati

Must be taking: Hydroxyurea

Disqualifiers: Family unwillingness

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 5

Duration: 12 months

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores the optimal use of hydroxyurea for children with sickle cell anemia, a condition where misshaped red blood cells can block blood flow. Researchers aim to determine the right dose of hydroxyurea, assess patient adherence to treatment, and evaluate the drug's impact on organ health and quality of life. Participants will either begin taking hydroxyurea or continue their existing treatment, based on their current use. The trial seeks children and young adults diagnosed with sickle cell anemia who are considering starting or already using hydroxyurea. As an unphased trial, it offers a unique opportunity to contribute to understanding and optimizing treatment for sickle cell anemia.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your healthcare provider.

Is there any evidence suggesting that hydroxyurea is likely to be safe for humans?

Research has shown that hydroxyurea is generally safe for people with sickle cell anemia. One study found it safe for short-term use in adults with this condition. Another study found that long-term use in children can reduce emergency room visits and hospital stays.

The FDA has already approved hydroxyurea for treating adults with sickle cell anemia, indicating it has passed safety tests. For children over five years old, studies have shown it is well-tolerated.

Research also suggests that specific doses of hydroxyurea are safe for children. Doses of 25-30 mg per kilogram of body weight each day have been used safely in some studies.

In summary, evidence supports that hydroxyurea is safe for both children and adults with sickle cell anemia. It helps reduce hospital visits and is generally well-tolerated. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Hydroxyurea is unique because it’s a well-established treatment for sickle cell anemia that's being optimized for better outcomes. Unlike traditional methods where dosing can be a bit of trial and error, this approach uses pharmacokinetic and pharmacodynamic data to tailor the starting dose more accurately for new patients. Researchers are excited because this personalized dosing could improve the effectiveness of the treatment from the start, potentially reducing complications and enhancing quality of life for patients.

What is the effectiveness track record for hydroxyurea in treating sickle cell anemia?

Research has shown that hydroxyurea effectively treats sickle cell anemia. Studies have found that it raises hemoglobin levels, aiding oxygen transport in the blood. It also reduces painful episodes and hospital visits for children with sickle cell disease. Over time, hydroxyurea continues to offer benefits, including fewer emergency room visits. This treatment has improved the quality of life for people with sickle cell anemia. Participants in this trial will receive hydroxyurea, with new participants starting treatment and others continuing their existing regimen. ^{3 4 6 7 8}

Who Is on the Research Team?

Charles Quinn, MD, MS

Principal Investigator

Children's Hospital Medical Center, Cincinnati

Are You a Good Fit for This Trial?

The TREAT study is for children and young adults aged 6 months to 21 years with sickle cell anemia who, along with their families and healthcare providers, decide to start hydroxyurea therapy. This includes those switching from transfusions to hydroxyurea. Families must be willing to consent and comply with the study.

Inclusion Criteria

I am between 6 months and 21 years old.

I have been diagnosed with sickle cell anemia.

I have decided with my family and doctor to start hydroxyurea therapy.

Exclusion Criteria

Family unwillingness to sign informed consent or comply with study treatments

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive hydroxyurea with dose prediction for the New Cohort and continuation for the Old Cohort

12 months

Monthly visits for dose adjustment and monitoring

Follow-up

Participants are monitored for safety, organ function, and quality of life after reaching MTD

Up to 10 years

Yearly visits for organ function assessment, monthly for adherence

Long-term Monitoring

Longitudinal monitoring of organ function and quality of life

Up to 21 years

Every 5 years for cardiac and neurological assessments

What Are the Treatments Tested in This Trial?

Interventions

• Hydroxyurea

Trial Overview This trial tests hydroxyurea in treating sickle cell anemia. It aims to predict the maximum tolerated dose using a model that considers how the body processes the drug (pharmacokinetics/pharmacodynamics), find urine markers of medication adherence, explore genetic factors affecting dosage tolerance, and monitor long-term effects on organ function and life quality.

How Is the Trial Designed?

Group I: Hydroxyurea Experimental Treatment 1 Intervention

All enrolled participants will receive hydroxyurea, but upon enrollment, participants will be identified as part of the "New Cohort" or "Old Cohort" "New Cohort" participants include those who are not receiving hydroxyurea therapy upon study entry. "Old Cohort" participants include those who are already receiving hydroxyurea therapy upon study entry. New Cohort participants will have starting dose predicted using PK/PD data and Old Cohort participants will continue dosing per clinical guidelines.

Hydroxyurea is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Hydroxyurea for:

• Sickle cell disease
• Chronic myeloid leukemia
• Solid tumors
• Thrombocythemia

Approved in European Union as Hydroxycarbamide for:

• Sickle cell syndrome
• Chronic myeloid leukaemia
• Essential thrombocythaemia
• Polycythaemia vera

Approved in Canada as Hydroxyurea for:

• Sickle cell disease
• Chronic myeloid leukemia
• Thrombocythemia

Who Is Running the Clinical Trial?

Children's Hospital Medical Center, Cincinnati

Lead Sponsor

Trials

844

Recruited

6,566,000+

Citations

1. ashpublications.org ashpublications.org/bloodadvances/article/9/14/3585/536727/Evaluating-the-long-term-benefits-of-hydroxyurea

Evaluating the long-term benefits of hydroxyurea in pediatric ... This study demonstrates that hydroxyurea has sustained clinical benefits in reducing ED visits and hospital days across years of use in children with SCA.

2. sciencedirect.com sciencedirect.com/science/article/pii/S247395292500237X

Evaluating the long-term benefits of hydroxyurea in ... Using contemporary quasi-experimental methods with real-world data, we showed hydroxyurea's sustained benefits over years of use. Abstract.

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11546997/

The Current Role of Hydroxyurea in the Treatment of Sickle ... This study showed that the MTD achieved greater increases in HbF and total hemoglobin levels, as well as a more significant reduction in white ...

4. hematology.org hematology.org/newsroom/press-releases/2025/hydroxyurea-effective-long-term-in-children-living-with-scd

Hydroxyurea Effective Long Term in Children Living With ... Hydroxyurea remains effective long-term in reducing emergency department visits and hospital days for children living with sickle cell disease (SCD), according ...

5. cochranelibrary.com cochranelibrary.com/cdsr/doi/10.1002/14651858.CD002202.pub3/full

Hydroxyurea (hydroxycarbamide) for sickle cell disease The evidence shows that hydroxyurea is likely to be effective in the short term at decreasing the frequency of painful episodes and raising HbF ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4022916/

Hydroxyurea in Sickle Cell Disease: Drug Review - PMC Signed written consent not required as hydroxyurea is FDA approved in adults with SCA and Phase II safety studies have been performed on children >age 5 years.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC2879711/

The Risks and Benefits of Long-term Use of Hydroxyurea in ... A randomized, controlled clinical trial established the efficacy and safety of short-term use of hydroxyurea in adult sickle cell anemia.

8. hematologyadvisor.com hematologyadvisor.com/features/hydroxyurea-dose-optimization-long-term-data-treatment-risk-africa/

Long-Term Data Suggest Hydroxyurea Dose Optimization ... Researchers determined hydroxyurea dosing at 25-30 mg/kg/day is feasible and safe for children with sickle cell anemia living in sub-Saharan