The U.S. Food and Drug Administration has given the green light to expand the approved use of a gene therapy made by Vertex Pharmaceuticals, now allowing children as young as two years old with certain inherited blood disorders — including sickle cell disease — to receive the treatment. This marks the first time any such therapy has been cleared for this younger age group.
The treatment, known as Casgevy, is a one-time therapy created using a patient’s own blood stem cells. Prior to this approval, it was only authorized for individuals aged 12 and older who had either sickle cell disease or transfusion-dependent beta thalassemia.
Here is what you need to know about the disease and the new approval:
Sickle cell disease is a hereditary blood condition that causes the body to produce abnormally shaped hemoglobin. This prevents red blood cells from effectively delivering oxygen throughout the body’s tissues, often leading to significant pain and health complications.
In a clinical trial involving children between the ages of five and under 12 who had sickle cell disease, all eight patients who could be evaluated experienced zero severe painful episodes — known as vaso-occlusive crises — for at least 12 consecutive months within the first two years following their infusion.
For children with beta thalassemia, eight out of nine evaluable patients achieved independence from blood transfusions for 12 straight months, with a median duration of 20.1 months.
The FDA moved quickly on this approval, completing its review in just 53 days after the application was submitted. That fast turnaround was made possible through the Commissioner’s National Priority Voucher, a newer program designed to speed up the review process for certain drug applications.
Back in 2023, the FDA had previously approved gene therapies from both Vertex Pharmaceuticals and Genetix Biotherapeutics for sickle cell disease, but only for patients 12 years of age and older.
Other established treatment options for sickle cell disease include bone marrow transplants, which depend on finding a compatible donor, and the chemotherapy medication hydroxyurea.
