Exagamglogene autotemcel (Casgevy – Vertex), a cell-based gene therapy recently approved for treatment of sickle cell disease1, has now been approved by the FDA for treatment of patients ≥12 years old with transfusion-dependent beta thalassemia. Casgevy is the first gene therapy that uses CRISPR/Cas9 gene-editing technology to be approved in the US for any disorder. Betibeglogene autotemcel (Zynteglo), an autologous lentiviral vector cell-based gene therapy, was approved in the US in 2022 for treatment of transfusion-dependent beta thalassemia.

Two cell-based gene therapies – exagamglogene autotemcel (Casgevy – Vertex) and lovotibeglogene autotemcel (Lyfgenia – Bluebird Bio) – have been approved by the FDA for treatment of sickle cell disease in patients ≥12 years old with recurrent vaso-occlusive crises. They are the first gene therapies to be approved in the US for use in sickle cell disease; Casgevy is the first treatment to be approved in the US that uses CRISPR/Cas9 gene-editing technology.

The FDA has approved two new drugs for sickle cell disease: crizanlizumab-tmca (Adakveo – Novartis), an IV P-selectin blocker, and voxelotor (Oxbryta – GBT), an oral hemoglobin S (HbS) polymerization inhibitor.

The FDA has approved an oral powder formulation of the amino acid L-glutamine (Endari – Emmaus) to reduce the acute complications of sickle cell disease in patients ≥5 years old. Endari is only the second drug to be approved for use in sickle cell disease; the antimetabolite hydroxyurea (Droxia) was approved 20 years ago. L-glutamine oral powder is also available by prescription as NutreStore for treatment of short bowel syndrome and over the counter as a dietary supplement.