On October 23, 2013, the site team at St. Jude Children’s Research Hospital in Memphis, TN, enrolled the last patient into the PTN hydroxyurea study. Overall, 8 sites—Duke University Medical Center, Medical College of Wisconsin, Columbia University Medical Center, Ann & Robert H. Lurie Children’s Hospital of Chicago, Children’s of Alabama, University of Arkansas for Medical Sciences, University of Texas Southwestern, and St. Jude—worked very hard to enroll the 39 patients needed for this study.

Hydroxyurea represents the only major medical breakthrough in sickle cell disease in the past 20 years, and it is the only drug approved by the U.S. Food and Drug Administration (FDA) for use in adults with sickle cell. In spite of the fact that it is not labeled for use in children, hydroxyurea is often used to treat children who exhibit signs of severe sickle cell disease. Recent data suggest that its use in infants with sickle cell is feasible, well-tolerated, and efficacious; however, only limited pharmacokinetic and pharmacodynamic studies of hydroxyurea use in children exist.

This study was designed to better understand how this drug works in children and to confirm its safety profile. Participants were given capsules or a liquid formulation of hydroxyurea, and blood samples were obtained after administration to determine drug concentrations in the body and its elimination. Study results are expected by the first half of 2014.

The PTN hydroxyurea trial has extended enrollment into Arm 1 of the study, which will target participants ages 2 to ≤5 years.

Enrollment into this trial is proceeding in two stages: the first stage (Arm 2) is focusing on children 5 to 17 years of age. Fourteen of 24 participants have been enrolled into this arm to date. Once the 8th patient was enrolled into this older cohort, the study team submitted an interim analysis of pharmacokinetic bioavailability and safety information to the Data and Safety Monitoring Board, which reviewed the data and recommended that the NICHD open enrollment of younger participants into Arm 1. The recommendation was approved on July 23, 2012.

Hydroxyurea represents the only major medical breakthrough in sickle cell disease in the past 20 years, and it is the only drug approved by the U.S. Food and Drug Administration (FDA) for use in adults with sickle cell. Treatment with hydroxyurea has been shown to significantly decrease the incidence of painful episodes and also reduces overall mortality in adult patients. In spite of the fact that the drug is not labeled for use in children, it is often used to treat children who exhibit signs of severe sickle cell disease. Recent data suggest that hydroxyurea therapy in infants with sickle cell is feasible, well-tolerated, and efficacious; however, only limited pharmacokinetic and pharmacodynamic studies of hydroxyurea use in children exist. The PTN is seeking to fill this knowledge gap.

The PTN hydroxyurea trial enrolled its 7th and 8th patients on June 12 and 14, 2012, thanks to the collective efforts of Nancy Green, MD, of Columbia University Medical Center, Robert Liem, MD, of Children’s Memorial Hospital in Chicago, and Courtney Thornburg, MD, of Duke University Medical Center.

Enrollment into this trial is proceeding in two stages: the first stage focused on children ages >5 – <17 years. The study protocol requires that, once the 8th patient is enrolled into this older cohort, the study team must submit an interim analysis of pharmacokinetic bioavailability and safety information to the Data and Safety Monitoring Board (DSMB). Once these data are reviewed, the DSMB will decide whether to allow enrollment of younger participants (ages 2 to ≤5 years) to begin. The DSMB plans to review these data on July 19, 2012.

Hydroxyurea represents the only major medical breakthrough in sickle cell disease in the past 20 years, and it is the only drug approved by the U.S. Food and Drug Administration (FDA) for use in adults with sickle cell. Treatment with hydroxyurea has been shown to significantly decrease the incidence of painful episodes and also reduces overall mortality in adult patients. In spite of the fact that the FDA has not approved hydroxyurea for pediatric use, it is often used to treat children who exhibit signs of severe sickle cell disease. Recent data suggest that hydroxyurea therapy in infants with sickle cell is feasible, well-tolerated, and efficacious; however, only limited pharmacokinetic and pharmacodynamic studies of hydroxyurea use in children exist. The PTN is seeking to fill this knowledge gap.

The PTN’s hydroxyurea (HU) study is kicking into high gear, with sites reportedly expecting an influx of at least 5 newly enrolled patients over the upcoming spring holiday.

Hydroxyurea is the only major drug breakthrough for the treatment of sickle cell disease within the past 20 years. Although it is approved by the Food and Drug Administration (FDA) to treat adults with sickle cell anemia, few studies have been done with HU in children to tell us how it is absorbed and expelled in maturing bodies. The PTN study will fill those knowledge gaps.

The HU study will enroll eligible children aged 2–17 years with a confirmed diagnosis of sickle cell anemia. For children aged 5–17 years, it will also explore whether the body handles the drug differently in liquid versus pill form. Results will provide information to help the FDA in considering approval of HU for use in infants and children with sickle cell anemia.

Click here for more information regarding the PTN hydroxyurea study.

Breaking news announcement

On January 27, 2012, the first patient was successfully enrolled into the PTN’s hydroxyurea (HU) study.

Hydroxyurea is the only major drug breakthrough for the treatment of sickle cell disease within the past 20 years. It is the only drug approved by the FDA to treat adults with sickle cell anemia, and so it is a part of the standard of care for those with severe sickle cell disease in the United States.

Few studies have been done with HU in children to tell us how it is absorbed and expelled. The PTN study will measure how much HU gets into the bloodstream at different time points in children, and how fast it is removed. The study will enroll eligible children ages 2–17 with a confirmed diagnosis of sickle cell anemia. For the children ages 5–17, the study will also explore whether the body handles HU differently in liquid versus pill form.

Study enrollment for all ages will take place during regularly scheduled clinic visits. Children will take their usual dose of HU, and small blood samples will be obtained over the course of a day. Study results will provide information to help the FDA in considering approval of HU for use in infants and children with sickle cell anemia.

The first enrolled patient provided the required blood draws over a full day in the clinic at Children’s Memorial Hospital in Chicago, IL, under the direction of Dr. Robert Liem, the study site principal investigator. The HU study plans to enroll 40 patients total over the course of several months.

Related: Hydroxyurea in pediatric patients with sickle cell anemia