America’s Vertex Pharmaceuticals has secured a label expansion through the FDA’s Commissioner’s National Priority Voucher (CNPV) programme that will now allow children as young as two-years-old to receive the costly gene therapy Casgevy for the one-time treatment of sickle cell disease (SCD) with recurrent vaso-occlusive crises (VOCs) or transfusion-dependent beta thalassemia (TDT).
Fierce Pharma reports that the ground-breaking therapy, which was co-developed by CRISPR Therapeutics, had already been approved for patients 12 and older.
The expansion opens the use of Casgevy to an additional 5 500 children in the United States, giving those patients and their families an opportunity to reduce the risk of organ damage that can result from either disorder.
“Earlier access to the …. therapy will allow clinicians and families to consider treatment before years of cumulative damage from these life-shortening diseases take hold,” said Haydar Frangoul, MD, medical director of HCA Healthcare’s Sarah Cannon Transplant and Cellular Therapy Programme at TriStar Centennial Children’s Hospital.
The expansion is supported in part by results from two ongoing phase 3 trials. In one, which included 11 children aged five to 12 with SCD, of the eight patients who were evaluable for efficacy, all achieved the primary endpoint with no severe VOCs for at least 12 consecutive months, according to an approval release from the FDA.
In the other trial of 15 TDT patients in the same age group, eight of the nine who could be evaluated for efficacy achieved the same standard, with a median duration of transfusion independence of 20 months.
Expanding the indication down to two years of age was also based on the known characteristics of Casgevy and clinical study data in both indications, Vertex said.
The approval falls under the CNPV programme established by former FDA commissioner Marty Makary, who announced his resignation in May amid a turbulent tenure at the regulator.
The CNPV programme was designed to drastically shorten review timelines for certain products and companies aligned with US national interests.
When Casgevy was originally approved in 2023 for SCD, it was hailed as the first medicine developed using the revolutionary CRISPR gene-editing system, which earned its inventors a Nobel Prize in 2020 and holds tantalising potential to cure other diseases for which there are no current treatments.
On the same day that the FDA originally approved Casgevy, the regulator also signed off on Bluebird Bio’s SCD gene therapy Lyfgenia. While uptake has been slow for both treatments – partly because of their respective prices of $2.2m and $3.1m – they are building momentum.
Sales for Casgevy came in at $116m in 2025 with 64 patients receiving infusions, including 30 in the fourth quarter. In the first three months of this year, Vertex listed Casgevy sales at $43m. The company added in its report that more than 500 patients have initiated treatment with Casgevy since it reached the market.
Meanwhile, in 2025, more than 150 patients completed initial cell collection for Lyfgenia, with more than 100 receiving infusions, according to private Genetix Biotherapeutics, which does not report sales of the treatment. After Bluebird was sold last year, private equity companies Carlyle and SK Capital established Genetix. Lyfgenia remains approved for SCD and TDT patients aged 12 and older.
See more from MedicalBrief archives:
Breakthrough sickle cell gene therapy a distant hope in Africa
FDA approves sickle cell treatment but obstacles remain
UK first to approve CRISPR-based treatment for sickle cell disease
Gene therapy: A game changer for those with sickle-cell disease
Sickle cell disease 11 times more deadly than thought – global study