Abstract

Patients with transfusion-dependent β-thalassemia and severe sickle cell disease suffer the burden of repeated blood transfusions and vaso-occlusive crises, respectively. Casgevy (exagamglogene autotemcel) consists of autologous CD34+ haematopoietic stem and progenitor cells edited, ex vivo, by CRISPR-Cas9 technology. Gene editing using Casgevy results in reduced expression of the BCL11A gene, and consequently, increased levels of foetal haemoglobin, which alleviate patient’s clinical symptoms. The approval of Casgevy marks the first time that marketing authorisation has been granted for a gene-editing technology in the EU, UK and the US.