An oral chemotherapy drug has demonstrated sustained safety and efficacy in managing sickle cell disease (SCD) in children, according to a comprehensive study published April 17 in the journal Blood Advances.
The research, conducted at Children's Hospital of Atlanta, found that children taking hydroxyurea had significantly fewer emergency room visits and spent fewer days hospitalized compared to those not receiving the treatment, even after accounting for disease severity and medication adherence.
"Our results reinforce that hydroxyurea, the most efficacious medicine available for sickle cell disease, continues to have really important benefits over time for pediatric patients," said lead researcher Dr. Paul George, a pediatric hematology/oncology fellow at Emory University School of Medicine in Atlanta.
Addressing a Common Inherited Blood Disorder
Sickle cell disease affects approximately 100,000 Americans, making it the most common inherited red blood cell disorder in the United States. The condition disproportionately impacts minority populations, with one in every 365 Black children and one in every 16,300 Hispanic children born with the disease.
The disorder causes red blood cells to become abnormally shaped, sticky, and rigid. These sickle-shaped cells can lodge in blood vessels, blocking circulation and leading to organ damage, infection vulnerability, and episodes of severe pain known as vaso-occlusive crises.
Hydroxyurea, administered once daily, helps red blood cells maintain their normal round and flexible shape rather than adopting the characteristic sickle form. This mechanism reduces the frequency and severity of pain crises while decreasing the need for blood transfusions, improving anemia, and lowering the risk of pulmonary vessel occlusion.
Long-Term Safety Confirmation
The study tracked 2,147 children under age 18 with sickle cell disease who received treatment at least three times between 2010 and 2021. Among these patients, 58% had used hydroxyurea, with an average treatment duration of approximately five years. The cohort included 304 children age 8 or older who maintained continuous therapy with the drug.
"Hydroxyurea has been a mainstay in sickle cell disease treatment for a long time, but was initially used as a chemotherapy, so there have always been some lingering fears about its safety and efficacy, especially for children," explained Dr. Wilbur Lam, a professor of pediatrics and biomedical engineering at Emory University and study co-author.
"This study can reassure patients and their families that this therapy, one of the most accessible for SCD, continues to be a safe option with a true benefit outside of a controlled setting," Lam added.
Clinical Outcomes and Adherence Factors
The research demonstrated that children consistently taking hydroxyurea experienced better clinical outcomes. However, researchers noted an important distinction regarding specific benefits.
"Overall, hydroxyurea remained effective over time in these children," George said. "However, one important takeaway from this study is that improvements in hemoglobin concentration – or reductions in anemia – were seen only in patients whose data indicated they were regularly taking the medication."
Current federal guidelines recommend offering hydroxyurea to patients with severe sickle cell disease starting between 9 and 12 months of age. This study provides additional evidence supporting these recommendations while emphasizing the importance of medication adherence for maximizing therapeutic benefits.
Implications for Clinical Practice
The findings have significant implications for pediatric hematology practice, particularly as they demonstrate the drug's sustained efficacy over an extended period in a real-world clinical setting rather than a controlled trial environment.
For families concerned about long-term medication use in children, the study offers reassurance regarding hydroxyurea's safety profile when used continuously for several years. The research also highlights the importance of consistent medication adherence to achieve optimal clinical benefits, particularly for improving anemia.
As one of the most accessible treatments for sickle cell disease, hydroxyurea represents a critical therapeutic option for a condition that disproportionately affects underserved populations. The confirmation of its long-term safety and efficacy in pediatric patients reinforces its position as a cornerstone therapy in managing this challenging inherited blood disorder.
