Exagamglogene autotemcel (exa-cel) was granted rolling review by the US Food and Drug Administration (FDA) for the potential treatment of sickle cell disease, according to a press release from Vertex Pharmaceuticals and CRISPR Therapeutics, the developers of the therapy.

Vertex plans to initiate a Biologics Licensing Application submission for rolling review of the treatment in November 2022 and complete it by the end of the first quarter of 2023.

“We continue to work with urgency to bring forward the first [clustered regularly interspaced short palindromic repeats (CRISPR)] therapy for a genetic disease, and one that holds potential to transform the lives of patients with sickle cell disease or beta thalassemia,” Nia Tatsis, PhD, executive vice president and chief regulatory and quality officer of Vertex, said.

Vertex also discussed the data necessary to support the marketing application of exa-cel with the European Medicines Agency (EMA) and the Medicines and Healthcare products Regulatory Agency (MHRA), and they are planning to submit those applications by the end of the year.

Exa-cel is an experimental, autologous, ex vivo CRISPR-based therapy being evaluated for the treatment of patients with sickle cell disease. It is currently being tested in a number of clinical trials. 

The treatment edits the patients’ own hematopoietic stem cells to produce high levels of fetal hemoglobin. It is hoped this could reduce vaso-occlusive crises in patients with sickle cell disease.

Read more about vaso-occlusive crises and other symptoms of sickle cell disease

Sickle cell disease is an autosomal recessive disease caused by a mutation in the gene that codes for the beta subunit of the hemoglobin protein. The mutation leads the hemoglobin protein to polymerize and causes the red blood cells to assume a sickle-like shape. These red blood cells can block capillaries, causing vaso-occlusive crises that can be extremely painful and debilitating.

Fetal hemoglobin is a type of hemoglobin that carries oxygen during fetal development. After birth, it switches to adult hemoglobin.

Exa-cel is also being tested in patients with transfusion-dependent beta thalassemia.


Vertex and CRISPR Therapeutics announce global exa-cel regulatory submissions for sickle cell disease and beta thalassemia in 2022. News release. Vertex Therapeutics Incorporated and CRISPR Therapeutics; September 27, 2022.