The Food and Drug Administration (FDA) has granted accelerated approval to the supplemental New Drug Application for Oxbryta (voxelotor) for the treatment of patients 4 to 11 years of age with sickle cell disease. Previously, the treatment was approved only for patients 12 years of age and older.

The FDA has also approved the New Drug Application for Oxbryta 300mg tablets for oral suspension, a new dispersible, once-daily tablet dosage form for patients 4 to 11 years of age as well as for older patients who have difficulty swallowing whole tablets. The new formulation is intended to be dispersed in room temperature clear liquid (eg, drinking water or clear soda) before swallowing. 

Oxbryta is a sickle hemoglobin polymerization inhibitor that binds to sickle hemoglobin and exhibits preferential partitioning to red blood cells. The approval for both applications was based on data from the open-label phase 2a HOPE-KIDS1 study ( Identifier: NCT02850406), which evaluated the efficacy and safety of Oxbryta in 45 patients aged 4 to 11 years with sickle cell disease. Patients received Oxbryta 300mg dispersible tablets according to body weight at baseline.

Findings showed that weight-based treatment with Oxbryta achieved rapid and sustained improvements in hemoglobin as well as concurrent reduction of hemolysis. Among patients who took at least one dose of Oxbryta, the hemoglobin response rate was 36% (n=16/45; 95% CI, 21.6-49.5).  As for safety, the most common adverse reactions (incidence greater than 10%) were pyrexia, vomiting, rash, abdominal pain, diarrhea, and headache. 

The new Oxbryta tablet is supplied as a 300mg grape-flavored dispersible tablet for oral suspension in 60- and 90-count bottles. Oxbryta is already available as a 500mg tablet in a 90-count bottle.

“Having the new formulation and approval down to 4 years of age is meaningful for families living with sickle cell disease and the community more broadly,” said Lewis Hsu, MD, PhD, chief medical officer of the Sickle Cell Disease Association of America. “Due to the many medical complications associated with sickle cell disease, kids face challenges every day in their ability to go to school and have a typical childhood. Adding another new FDA-approved treatment option for children will enhance care and provide more choices for children living with sickle cell disease.” 


  1. FDA approves drug to treat sickle cell disease in patients aged 4 up to 11 years. News release. US Food and Drug Administration. Accessed December 17, 2021. 
  2. US FDA approves supplemental New Drug Application for expanded indication of Oxbryta® (voxelotor) for children as young as 4 years of age with sickle cell disease. News release. Global Blood Therapeutics, Inc. Accessed December 17, 2021.
  3. Oxbryta. Package insert. Global Blood Therapeutics, Inc.; 2021. Accessed December 17, 2021.