Editas Medicine Announces Positive Initial EDIT-301 Safety and Efficacy Data from the First Four Patients Treated in the RUBY Trial and the First Patient Treated in the EdiTHAL Trial - Seite 2

RUBY Trial
Safety
All treated patients demonstrated successful neutrophil and platelet engraftment. No serious adverse events (SAEs) were reported after EDIT-301 infusion, and no adverse events (AEs) related to EDIT-301 treatment have been observed. All four treated patients in the RUBY trial are free from vaso-occlusive events since infusion with EDIT-301, with 2-10 months follow-up.

Efficacy
Patient 1 (male) has had 10 months of follow-up. Patient 1’s total hemoglobin returned to normal physiological level of 16.4g/dL (male normal range: 13.6–18.0 g/dL) at five months after infusion of EDIT-301 and has been maintained at this level at the 10-month follow-up. In addition, Patient 1’s fetal hemoglobin fraction increased from 5% at baseline to 45.4% five months after treatment with EDIT-301 and 43.4% at the 10-month follow-up.

Patient 2 (female) has had 6 months of follow-up. Patient 2’s total hemoglobin reached normal physiological level of 12.7 g/dL (female normal range: 12.0–16.0 g/dL) at five months after infusion of EDIT-301 and fetal hemoglobin increased from 10.8% at baseline to 51.3% at the 6-month follow-up.

Patient 3 (female) and Patient 4 (male) have had three and two months of follow-up, respectively. Increases in total hemoglobin and fetal hemoglobin fractions for Patient’s 3 and 4 are following similar trajectories as seen in Patients 1 and 2 at the same timepoints.

EdiTHAL Trial
Safety
The first treated patient (male) in the EdiTHAL trial has had 1.5 months of follow-up. Patient 1 had successful neutrophil and platelet engraftment within 30 days of EDIT-301 infusion, and the safety profile has been consistent with that of myeloablative busulfan conditioning and autologous hematopoietic stem cell transplant. No serious adverse events occurred after EDIT-301 infusion, and no adverse events reported were related to treatment with EDIT-301.

Efficacy
The first EdiTHAL patient’s experience with EDIT-301 resembles that of the first four RUBY patients, achieving a fetal hemoglobin fraction of 34.9% representing 4 g/dL of total hemoglobin at 1.5 months post-treatment.

“These promising data support our belief that EDIT-301 can be a clinically differentiated, one-time, durable medicine that can provide life changing clinical benefits to patients with sickle cell disease and beta thalassemia long term, specifically driving early and robust correction of anemia and sustained increases in fetal hemoglobin,” said Baisong Mei, MD, Ph.D., Senior Vice President and Chief Medical Officer, Editas Medicine. “I would like to thank the clinical trial participants, their families, clinicians, and colleagues at collaborating institutions that contribute to the RUBY and EdiTHAL trials. We remain on-track to dose 20 RUBY patients by year-end, and we look forward to sharing further RUBY and EdiTHAL clinical updates later this year.”