Editas Medicine, Inc. announced that a scientific abstract detailing safety and efficacy clinical data from the Phase 1/2 RUBY trial of EDIT-301 in patients with severe sickle cell disease has been accepted for an oral presentation at the European Hematology Association (EHA) Hybrid Congress being held June 8-11, 2023, in Frankfurt, Germany, and via live stream. Key data from multiple patients will be shared in the oral presentation at EHA, confirming initial clinical data, include: Efficacy data, including total hemoglobin, fetal hemoglobin, percentage of F-cells, mean corpuscular fetal hemoglobin, and vaso-occlusive events (VOEs) post-infusion with EDIT-301. Safety data, including neutrophil and platelet engraftment.

Oral Presentation Details: Title: EDIT-301 Shows Promising Preliminary Safety and Efficacy Results in the Phase I/II Clinical Trial (RUBY) of Patients with Severe Sickle Cell Disease Using Highly Specific and Efficient AsCas12a Enzyme Presenting Author: Rabi Hanna, M.D., Department of Pediatric Hematology Oncology and Blood and Marrow Transplantation, Cleveland Clinic Children's, Cleveland, OH, United States Date/Time: Saturday, June 10, 2023, 4:30 – 5:45 p.m. CEST/10:30 – 11:45 a.m. EDT Location: Harmonie 1, Messe Frankfurt Session: s437 Gene therapy and cellular immunotherapy – Clinical EDIT-301 is currently being investigated in a clinical study in patients with severe sickle cell disease (RUBY trial, NCT04853576) and transfusion-dependent beta thalassemia (EDITHAL trial, NCT05444894). In addition to the clinical data update from the RUBY trial at EHA and in a Company-sponsored webinar next month, the Company will present a further clinical update from the RUBY trial by year-end. Additionally, the Company is on-track to dose 20 patients in the RUBY trial by year-end.

Sickle cell disease is an inherited blood disorder caused by a mutation in the beta-globin gene that leads to polymerization of the sickle hemoglobin (HbS). In sickle cell disease, the red blood cells are misshapen in a sickle shape instead of a typical disc shape. The abnormal shape causes the red blood cells to have shortened lifespan and to block blood flow causing anemia, pain crises, organ failure, and early death.

There are an estimated 100,000 people in the United States currently living with sickle cell disease. Higher levels of fetal hemoglobin (HbF) inhibit HbS polymerization, thus reducing the manifestation of sickling. EDIT-301 is an experimental cell therapy medicine under investigation for the treatment of severe sickle cell disease (SCD) and transfusion-dependent beta thalassemia (TDT).

EDIT-301 consists of patient-derived CD34+ hematopoietic stem and progenitor cells edited at the gamma globin gene (HBG1 and HBG2) promoters, where naturally occurring fetal hemoglobin (HbF) inducing mutations reside, by a highly specific and efficient proprietary engineered AsCas12a nuclease. Red blood cells derived from EDIT-301 CD34+ cells demonstrate a sustained increase in fetal hemoglobin production, which has the potential to provide a one-time, durable treatment benefit for people living with severe SCD and TDT.