Hydroxyurea Optimization Through Precision Study (HOPS)

  • End date
    Dec 31, 2023
  • participants needed
  • sponsor
    Children's Hospital Medical Center, Cincinnati
Updated on 10 February 2022
sickle hemoglobin
hemoglobin f


Hydroxyurea Optimization through Precision Study (HOPS) is a prospective, multi-center, randomized trial that will directly compare a novel, individualized dosing strategy of hydroxyurea to standard weight-based dosing for children with SCA. The primary objective of the study is to evaluate whether a pharmacokinetics-based starting hydroxyurea dose thieves superior fetal hemoglobin response to to standard weight-based initial dosing. Patients will be recruited from the pediatric sickle cell clinic at Cincinnati Children's Hospital Medical Center and from additional pediatric sickle cell centers within the United States.


The trial will recruit patients who have decided to initiate hydroxyurea therapy. All participants will have pharmacokinetics studies performed at baseline, following a 20 mg/kg oral dose of hydroxyurea. Pharmacokinetic sampling will use a sparse sampling approach, requiring collection of blood at 3 time points (15 minutes, 60 minutes, 180 minutes) following the hydroxyurea dose. Enrolled participants will be randomized to receive either hydroxyurea using a starting dose of 20 mg/kg/day (Standard Arm) or a personalized PK-guided dose (Alternative Arm) to target an area under the curve (AUC) of 115 mg*h/L based to approximate hydroxyurea exposure seen when patients are escalated to maximum tolerated dose (MTD).

Following randomization and selection of the initial dose, participants in both arms will follow the same procedures of laboratory medication holds for hematological toxicity. The primary endpoint is fetal hemoglobin (HbF) six months following the initiation of hydroxyurea therapy with the hypothesis that participants starting with a PK-guided dose will achieve HbF at least 5% greater than those starting with a 20 mg/kg dose. Based upon the estimated number of new hydroxyurea starts at each site, it is anticipated that it will take 24 months to enroll the 116 participants required to achieve sufficient power to assess the primary endpoint. The study will conclude for each participant 12 months following hydroxyurea initiation.

Condition Sickle Cell Disease, Sickle Cell Anemia
Treatment hydroxyurea
Clinical Study IdentifierNCT03789591
SponsorChildren's Hospital Medical Center, Cincinnati
Last Modified on10 February 2022


Yes No Not Sure

Inclusion Criteria

Diagnosis of sickle cell anemia (HbSS, HbSD, HbS/β0-thalassemia, or similarly severe SCA genotype)
Age 6 months to 21 years at the time of enrollment
Clinical decision by patient, family, and healthcare providers to initiate hydroxyurea therapy

Exclusion Criteria

Current treatment with chronic, monthly blood transfusions or erythrocytapheresis
Treatment with hydroxyurea within the past 3 months
Hemoglobin SC disease, HbS/β+-thalassemia
Current treatment with other investigational sickle cell medications
Current known pregnancy or lactation
Clear my responses

How to participate?

Step 1 Connect with a study center
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact



Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note