N. Engl. J. Med. 378, 1479–1493 (2018).

In the most severe form of beta thalassemia, transfusion-dependent beta thalassemia, affected individuals are dependent on blood transfusion, which is challenging owing to limited donors and complications associated with transfusion. Gene therapy has previously been shown to hold promise in an individual with beta thalassemia.

A team of researchers from Chicago report the interim result from two phase 1/2 clinical studies in which patients’ own CD34+ cells were isolated and transduced with a lentiviral vector to deliver the beta globin gene. The cells were then reinjected into the patients.

In their study of 22 patients, the team found that this gene therapy approach reduced or eliminated the need for further transfusions, and there were no adverse events.