Researchers discovered that the drug voxelotor is safe and efficient for pediatric patients with sickle cell disease (SCD) and published their results in Pediatric Blood & Cancer.

SCD forces the body to operate under conditions of deoxygenation, triggering chronic cycles of anemia, hemolysis, and vaso-occlusive crises. These repetitive ischemic injuries can eventually cause end-organ damage and early mortality.

Evidence indicates that clinical deterioration in patients with SCD starts young. By the age of 6 years, around a quarter of children with SCD will display evidence of silent cerebral infarct, and around half will have had an episode of acute chest syndrome. In addition, some children with SCD develop splenic and renal dysfunction, worsening prognosis considerably.

Read more about SCD epidemiology 

Voxelotor is an oral, once-daily hemoglobin polymerization inhibitor approved for use in the US in 2019 for the treatment of SCD in adults and teenagers 12 years of age and over. “Given the childhood manifestation pattern and progressive nature of SCD, treatment of pediatric patients with disease-modifying agents such as voxelotor may provide clinical benefit if started at a young age,” the authors said.

The research team thus decided to investigate the safety and efficacy of voxelotor in children between the ages of 4 and 11 years. They recruited 45 patients with SCD between that age range. The participants received voxelotor treatment (with the dosage calculated based on weight) for up to 48 weeks.

The results demonstrated that at week 24, 47% of patients had more than 1.0 g/dL of an increase in hemoglobin concentration from baseline, 35% had more than 1.5 g/dL of an increase, and 21% had more than 2.0 g/dL of an increase. Importantly, voxelotor was also well-tolerated, with no new safety concerns have emerged during this clinical trial.

“These data support the use of voxelotor in pediatric patients aged 4 years and older with SCD as a strategy to target the disease at an early stage and impede or prevent disease sequelae,” the researchers concluded.


Estepp JH, Kalpatthi R, Woods G, et al. Safety and efficacy of voxelotor in pediatric patients with sickle cell disease aged 4 to 11 yearsPediatr Blood Cancer. Published online April 21, 2022. doi:10.1002/pbc.29716