FDA lifts hold, first patient dosed in Editas sickle cell gene editing trial

July 29, 2022

Editas announced this week that the first patient had been dosed in its phase 1/2 RUBY trial of EDIT-301 for the treatment of severe sickle cell disease (SCD), and that the FDA had lifted the partial hold on the trial. 

The clinical hold came when the FDA asked the company to develop and submit to an improved potency assay prior to enrolling in the efficacy phase of the trial. 

The drug, which consists of patient-derived CD34+ hematopoietic stem and progenitor cells edited at the gamma-globin gene (HBG1 and HBG2) promoters, where naturally disease occurring mutations arise uses the company’s engineered proprietary AsCas12a enzyme. 

Cells treated with EDIT-301 have shown in trials to have a sustained increase in fetal hemoflobin promoter, which could potentially provide a one-time treatment for people living with severe SCD and TDT. 

“It is an exciting time at Editas as we continue to build momentum for our EDIT-301 program,” said Gilmore O’Neill,  president and CEO at Editas Medicine. “Dosing and successful engraftment of the first patient coupled with the FDA’s removal of the partial clinical hold on the RUBY trial are important steps toward our goal of bringing this new and promising treatment to people living with sickle cell disease and thalassemia.”